National Library of Energy BETA

Sample records for mu unr au

  1. CoMuEx

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    CoMuEx CoMuEx CoMuEx researchers apply high-resolution diagnostics to study fluid dynamics in extreme environments to support modern technologies with a diverse applications, including efficient nuclear energy, stockpile stewardship and astrophysics. Contact Center Director Malcolm J. Andrews (505) 606-1430 Email Director of Applications Robert A. Gore (505) 665-0976 Email Leading the Lab in areas concerning mix and turbulence under extreme conditions The Center of Mixing Under Extreme

  2. Assignment of the luminescing states of [Au{sup 1}Rh{sup 1}({sup t}BuNC){sub 2}({mu}-dppm){sub 2}][PF{sub 6}]{sub 2}

    SciTech Connect (OSTI)

    Striplin, D.R.; Crosby, G.A.

    1995-07-13

    Fluorescence, phosphorescence, and excitation spectra were measured on the title compound. These results were augmented with polarization ratios obtained at 77 K and detailed studies of the temperature dependence of the phosphorescence in the 77-4 K range. The phosphorescence decay rate at K was also recorded as a function of an applied magnetic field. All the results are consistent with a 4d{sub z}Rh{sup 1} {yields} 6p{sub 2}Au{sup 1} orbital promotion leading to emitting {sup 1}A, {sup 3}A{sub 1} terms in pseudo-C{sub 2v} symmetry. The {sup 3}A{sub 1} term is split by spin-orbit coupling into a forbidden A{sub 2} state lying lowest followed by a quasi-degenerate pair, [B{sub 1}(x), B{sub 2}(y)] lying approximately 16 cm{sup -1} higher that decays >500 times faster than the lowest one. 28 refs., 6 figs.

  3. Retrofitting and the mu Problem

    SciTech Connect (OSTI)

    Green, Daniel; Weigand, Timo; /SLAC /Stanford U., Phys. Dept.

    2010-08-26

    One of the challenges of supersymmetry (SUSY) breaking and mediation is generating a {mu} term consistent with the requirements of electro-weak symmetry breaking. The most common approach to the problem is to generate the {mu} term through a SUSY breaking F-term. Often these models produce unacceptably large B{mu} terms as a result. We will present an alternate approach, where the {mu} term is generated directly by non-perturtative effects. The same non-perturbative effect will also retrofit the model of SUSY breaking in such a way that {mu} is at the same scale as masses of the Standard Model superpartners. Because the {mu} term is not directly generated by SUSY breaking effects, there is no associated B{mu} problem. These results are demonstrated in a toy model where a stringy instanton generates {mu}.

  4. Search for the Rare Decays B^+ -> mu^+ mu^- K^+, B^0 -> mu^+ mu^- K^*0(892), and B^0_s -> mu^+ mu^- phi at CDF

    SciTech Connect (OSTI)

    Aaltonen, T.; Adelman, J.; Akimoto, T.; Albrow, M.G.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A.; Antos, J.; Apollinari, G.; /Fermilab

    2008-04-01

    The authors search for b {yields} s{mu}{sup +}{mu}{sup -} transitions in B meson (B{sup +}, B{sup 0}, or B{sub s}{sup 0}) decays with 924 pb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV collected with the CDF II detector at the Fermilab Tevatron. They find excesses with significances of 4.5, 2.9, and 2.4 standard deviations in the B{sup +} {yields} {mu}{sup +}{mu}{sup -}K{sup +}, B{sup 0} {yields} {mu}{sup +}{mu}{sup -}K*(892){sup 0}, and B{sub s}{sup 0} {yields} {mu}{sup +}{mu}{sup -}{phi} decay modes, respectively. Using B {yields} J/{psi}h (h - K{sup +}, K*(892){sup 0}, {phi}) decays as normalization channels, they report branching fractions for the previously observed B{sup +} and B{sup 0} decays as normalization channels, they report branching fractions for the previously observed B{sup +} and B{sup 0} decays, {Beta}(B{sup +} {yields} {mu}{sup +}{mu}{sup -}K{sup +}) = (0.59 {+-} 0.15 {+-} 0.04) x 10{sup -6}, and {Beta}(B{sup 0} {yields} {mu}{sup +}{mu}{sup -}K*(892){sup 0}) = (0.81 {+-} 0.30 {+-} 0.10) x 10{sup -6}, where the first uncertainty is statistical, and the second is systematic. These measurements are consistent with the world average results, and are competitive with the best available measurements. They set an upper limit on the relative branching fraction {Beta}(B{sub s}{sup 0}{yields}{mu}{sup +}{mu}{sup -}{phi})/{Beta}(B{sub s}{sup 0}{yields}J/{psi}{phi}) < 2.6(2.3) x 10{sup -3} at the 95(90)% confidence level, which is the most stringent to date.

  5. Mixed-mu superconducting bearings

    DOE Patents [OSTI]

    Hull, John R. (Hinsdale, IL); Mulcahy, Thomas M. (Western Springs, IL)

    1998-01-01

    A mixed-mu superconducting bearing including a ferrite structure disposed for rotation adjacent a stationary superconductor material structure and a stationary permanent magnet structure. The ferrite structure is levitated by said stationary permanent magnet structure.

  6. Mixed-mu superconducting bearings

    DOE Patents [OSTI]

    Hull, J.R.; Mulcahy, T.M.

    1998-03-03

    A mixed-mu superconducting bearing is disclosed including a ferrite structure disposed for rotation adjacent a stationary superconductor material structure and a stationary permanent magnet structure. The ferrite structure is levitated by said stationary permanent magnet structure. 9 figs.

  7. Cecilia Muñoz

    Broader source: Energy.gov [DOE]

    Cecilia Muñoz is the Assistant to the President and Director of the Domestic Policy Council, which coordinates the domestic policy-making process in the White House. 

  8. Search for $B_s \\to \\mu^+\\mu^-$ and $B_d \\to \\mu^+\\mu^-$ Decays with CDF II

    SciTech Connect (OSTI)

    Aaltonen, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A.; Antos, J.; Apollinari, G.; Appel, J.A.; Apresyan, A.; Arisawa, T.; /Waseda U. /Dubna, JINR

    2011-07-01

    A search has been performed for B{sub s}{sup 0} {yields} {mu}{sup +}{mu}{sup -} and B{sup 0} {yields} {mu}{sup +}{mu}{sup -} decays using 7 fb{sup -1} of integrated luminosity collected by the CDF II detector at the Fermilab Tevatron collider. The observed number of B{sup 0} candidates is consistent with background-only expectations and yields an upper limit on the branching fraction of {Beta}(B{sup 0} {yields} {mu}{sup +}{mu}{sup -}) < 6.0 x 10{sup -9} at 95% confidence level. We observe an excess of B{sub s}{sup 0} candidates. The probability that the background processes alone could produce such an excess or larger is 0.27%. The probability that the combination of background and the expected standard model rate of B{sub s}{sup 0} {yields} {mu}{sup +}{mu}{sup -} could produce such an excess or larger is 1.9%. These data are used to determine {Beta}(B{sub s}{sup 0} {yields} {mu}{sup +}{mu}{sup -}) = (1.8{sub -0.9}{sup +1.1}) x 10{sup -8} and provide an upper limit of {Beta}(B{sub s}{sup 0} {yields} {mu}{sup +}{mu}{sup -}) < 4.0 x 10{sup -8} at 95% confidence level.

  9. Measurement of the Forward-Backward Asymmetry in the $B \\to K^{(*)} \\mu^+ \\mu^-$ Decay and First Observation of the $B^0_s \\to \\phi \\mu^+ \\mu^-$ Decay

    SciTech Connect (OSTI)

    Aaltonen, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A.; Antos, J.; Apollinari, G.; Appel, J.A.; Apresyan, A.; Arisawa, T.; /Waseda U. /Dubna, JINR

    2011-01-01

    We reconstruct the rare decays B{sup +} {yields} K{sup +} {mu}{sup +}{mu}{sup -}, B{sup 0} {yields} K*(892){sup 0} {mu}{sup +}{mu}{sup -}, and B{sub s}{sup 0} {yields} {phi}(1020){mu}{sup +}{mu}{sup -} in a data sample corresponding to 4.4 fb{sup -1} collected in p{bar p} collisions at {radical}s = 1.96 TeV by the CDF II detector at the Fermilab Tevatron Collider. Using 120 {+-} 16 B{sup +} {yields} K{sup +} {mu}{sup +}{mu}{sup -} and 101 {+-} 12 B{sup 0} {yields} K*{sup 0} {mu}{sup +}{mu}{sup -} decays we report the branching ratios. In addition, we report the measurement of the differential branching ratio and the muon forward-backward asymmetry in the B{sup +} and B{sup 0} decay modes, and the K*{sup 0} longitudinal polarization in the B{sup 0} decay mode with respect to the squared dimuon mass. These are consistent with the theoretical prediction from the standard model, and most recent determinations from other experiments and of comparable accuracy. We also report the first observation of the B{sub s}{sup 0} {yields} {phi}{mu}{sup +}{mu}{sup -} decay and measure its branching ratio {Beta}(B{sub s}{sup 0} {yields} {phi}{mu}{sup +}{mu}{sup -}) = [1.44 {+-} 0.33 {+-} 0.46] x 10{sup -6} using 27 {+-} 6 signal events. This is currently the most rare B{sub s}{sup 0} decay observed.

  10. 12. mu. m band tunable ammonia laser

    SciTech Connect (OSTI)

    Li Yuteh; Kuang Ichung; Hsun Hungtao

    1987-01-01

    The 9.4 ..mu..m R(30) line from a TEA-CO/sub 2/ laser was used to pump a NH/sub 3/ laser. Tunable NH/sub 3/ laser emission in the 12 ..mu..m band has been obtained. The output energy at 12.247, 12.261, and 12.079 ..mu..m is 18.6, 23, and 26 mJ, respectively.

  11. Relating B_S Mixing and B_S to mu+mu- with New Physics (Journal...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Relating BS Mixing and BS to mu+mu- with New Physics Citation Details In-Document Search Title: Relating BS Mixing and BS to mu+mu- with New Physics We perform...

  12. Relating B_S Mixing and B_S to mu+mu- with New Physics (Journal...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Relating BS Mixing and BS to mu+mu- with New Physics Citation Details In-Document Search Title: Relating BS Mixing and BS to mu+mu- with New Physics You are...

  13. B \\to Mu Mu And B \\to Tau Nu Decays (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Citation Details In-Document Search Title: B to Mu Mu And B to Tau Nu Decays Authors: Scuri, Fabrizio ; INFN, Pisa Publication Date: 2013-06-18 OSTI Identifier: 1084294 Report ...

  14. Helio Micro Utility Helio mU | Open Energy Information

    Open Energy Info (EERE)

    Helio mU Jump to: navigation, search Name: Helio Micro Utility (Helio mU) Place: Berkeley, California Zip: 94710 Product: Helio mU provides independent financing and risk...

  15. AU Organization Chart | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AU Organization Chart AU Organization Chart AU Organization Chart: December 22, 2015 PDF icon AU Organization Chart: December 22, 2015 More Documents & Publications FTCP Senior ...

  16. Updated Search for the Flavor-Changing Neutral-Current Decay $D^0 \\to \\mu^+ \\mu^-$

    SciTech Connect (OSTI)

    Aaltonen, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A.; Antos, J.; Apollinari, G.; Appel, J.A.; Apresyan, A.; Arisawa, T.; /Waseda U. /Dubna, JINR

    2010-08-01

    We report on a search for the flavor-changing neutral-current decay D{sup 0} {yields} {mu}{sup +}{mu}{sup -} in p{bar p} collisions at {radical}s = 1.96TeV using 360 pb{sup -1} of integrated luminosity collected by the CDF II detector at the Fermilab Tevatron collider. A displaced vertex trigger selects long-lived D{sup 0} candidates in the {mu}{sup +}{mu}{sup -}, {pi}{sup +}{pi}{sup -}, and K{sup -}{pi}{sup +} decay modes. We use the Cabibbo-favored D{sup 0} {yields} K{sup -}{pi}{sup +} channel to optimize the selection criteria in an unbiased manner, and the kinematically similar D{sup 0} {yields} {pi}{sup +}{pi}{sup -} channel for normalization. We set an upper limit on the branching fraction {Beta}(D{sup 0} {yields} {mu}{sup +}{mu}{sup -}) < 2.1 x 10{sup -7} (3.0 x 10{sup -7}) at the 90% (95%) confidence level.

  17. [(eta5-PentamethylcyclopentadienylYb(III)(5,5'-dimethyl-2,2-bipyridyl)mu-OH)2(mu

    Office of Scientific and Technical Information (OSTI)

    2-trifluoromethylsulfanato-O,O')][tetraphenylborate](5,5'-dimethyl-2,2-bipyridyl) (Journal Article) | SciTech Connect Journal Article: [(eta5-PentamethylcyclopentadienylYb(III)(5,5'-dimethyl-2,2-bipyridyl)mu-OH)2(mu 2-trifluoromethylsulfanato-O,O')][tetraphenylborate](5,5'-dimethyl-2,2-bipyridyl) Citation Details In-Document Search Title: [(eta5-PentamethylcyclopentadienylYb(III)(5,5'-dimethyl-2,2-bipyridyl)mu-OH)2(mu

  18. [(eta5-PentamethylcyclopentadienylYb(III)(5,5'-dimethyl-2,2-bipyridyl)mu-OH)2(mu

    Office of Scientific and Technical Information (OSTI)

    2-trifluoromethylsulfanato-O,O')][tetraphenylborate](5,5'-dimethyl-2,2-bipyridyl) (Journal Article) | SciTech Connect Journal Article: [(eta5-PentamethylcyclopentadienylYb(III)(5,5'-dimethyl-2,2-bipyridyl)mu-OH)2(mu 2-trifluoromethylsulfanato-O,O')][tetraphenylborate](5,5'-dimethyl-2,2-bipyridyl) Citation Details In-Document Search Title: [(eta5-PentamethylcyclopentadienylYb(III)(5,5'-dimethyl-2,2-bipyridyl)mu-OH)2(mu

  19. MU(& Ge-+v,

    Office of Legacy Management (LM)

    fil MU(& Ge-+v, . !d R&arch & Development b This document consists of 6 Contract Ho. pages and - . --------------_____---. figures No.--~--of.--~~-_-copies, Series,&,, This subcontract entered into this 20 day 0fSepte~ber , 1943, by and between the University of Cliicago, a corporation not for pecuniary profit organized under the ICVS of the Stnto of Illinois, of Chicago, Illinois (hereinafter called "the Contractor") and Yiolverine Tube Divisionof Caluzet 2 Eecla

  20. Search for the Decay Modes D0 to e+ e-, D0 to mu+ mu-, and D0 to e+/- mu+/-

    SciTech Connect (OSTI)

    Lees, J. P.

    2012-08-03

    We present searches for the rare decay modes D{sup 0} {yields} e{sup +}e{sup -}, D{sup 0} {yields} {mu}{sup +}{mu}{sup -}, and D{sup 0} {yields} e{sup {+-}}{mu}{sup {-+}} in continuum e{sup +}e{sup -} {yields} c{bar c} events recorded by the BABAR detector in a data sample that corresponds to an integrated luminosity of 468 fb{sup -1}. These decays are highly GIM suppressed but may be enhanced in several extensions of the Standard Model. Our observed event yields are consistent with the expected backgrounds. An excess is seen in the D{sup 0} {yields} {mu}{sup +}{mu}{sup -} channel, although the observed yield is consistent with an upward background fluctuation at the 5% level. Using the Feldman-Cousins method, we set the following 90% confidence level intervals on the branching fractions: {Beta}(D{sup 0} {yields} e{sup +}e{sup -}) < 1.7 x 10{sup -7}, {Beta}(D{sup 0} {yields} {mu}{sup +}{mu}{sup -}) within [0.6, 8.1] x 10{sup -7}, and {Beta}(D{sup 0} {yields} e{sup {+-}}{mu}{sup {-+}}) < 3.3 x 10{sup -7}.

  1. Rationalization of Au concentration and distribution in AuNi...

    Office of Scientific and Technical Information (OSTI)

    Rationalization of Au concentration and distribution in AuNi@Pt core-shell nanoparticles for oxygen reduction reaction Citation Details In-Document Search This content will become ...

  2. Observation of the decay Xi0 ---> Sigma+ mu- anti-nu(mu)

    SciTech Connect (OSTI)

    Alavi-Harati, A.; Alexopoulos, T.; Arenton, M.; Barbosa, R.F.; Barker, A.R.; Barrio, M.; Bellantoni, L.; Bellavance, A.; Blucher, E.; Bock, G.J.; Bown, C.; Bright, S.; Cheu, E.; Coleman, R.; Corcoran, M.D.; Cox, B.; Erwin, A.R.; Escobar, C.O.; Ford, R.; Glazov, A.; Golossanov, A.; /Arizona U. /UCLA /UC, San Diego /Campinas State U. /Chicago U., EFI /Colorado U. /Elmhurst Coll. /Fermilab /Osaka U. /Rice U. /Sao Paulo U. /Virginia U. /Wisconsin U., Madison

    2005-04-01

    The {Xi}{sup 0} muon semi-leptonic decay has been observed for the first time with nine identified events using the KTeV beam line and detector at Fermilab. The decay is normalized to the {Xi}{sup 0} beta decay mode and yields a value for the ratio of decay rates {Lambda}({Xi}{sup 0} {yields} {Sigma}{sup +}{mu}{sup -}{bar {nu}}{sub {mu}})/{Lambda}({Xi}{sup 0} {yields} {Sigma}{sup +}e{sup -} {bar {nu}}{sub e}) of (1.8{sub -0.5}{sup +0.7}(stat.) {+-} 0.2(syst.)) x 10{sup -2} at the 68% confidence level. This is in agreement with the SU(3) flavor symmetric quark model.

  3. Magnetoresistance of Au films

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zhang, D. L.; Song, X. H.; Zhang, X; Zhang, Xiaoguang

    2014-01-01

    Measurement of the magnetoresistance (MR) of Au films as a function of temperature and film thickness reveals a strong dependence on grain size distribution and clear violation of the Kohler s rule. Using a model of random resistor network, we show that this result can be explained if the MR arises entirely from inhomogeneity due to grain boundary scattering and thermal activation of grain boundary atoms.

  4. Analysis of vapor-liquid-solid mechanism in Au-assisted GaAs nanowire growth

    SciTech Connect (OSTI)

    Harmand, J.C.; Patriarche, G.; Pere-Laperne, N.; Merat-Combes, M-N.; Travers, L.; Glas, F.

    2005-11-14

    GaAs nanowires were grown by molecular-beam epitaxy on (111)B oriented surfaces, after the deposition of Au nanoparticles. Different growth durations and different growth terminations were tested. After the growth of the nanowires, the structure and the composition of the metallic particles were analyzed by transmission electron microscopy and energy dispersive x-ray spectroscopy. We identified three different metallic compounds: the hexagonal {beta}{sup '}Au{sub 7}Ga{sub 2} structure, the orthorhombic AuGa structure, and an almost pure Au face centered cubic structure. We explain how these different solid phases are related to the growth history of the samples. It is concluded that during the wire growth, the metallic particles are liquid, in agreement with the generally accepted vapor-liquid-solid mechanism. In addition, the analysis of the wire morphology indicates that Ga adatoms migrate along the wire sidewalls with a mean length of about 3 {mu}m.

  5. A Search for the B^0 to e^+ e^- \\gamma and B^0 to \\mu^+ \\mu^- \\gamma Decays

    SciTech Connect (OSTI)

    Aubert, B.

    2006-09-27

    With the BABAR detector at the PEP-II asymmetric B Factory at SLAC, they present the first search for the decays B{sup 0} {yields} {ell}{sup +}{ell}{sup -}{gamma} ({ell} = e, {mu}). Using a data set of 292 fb{sup -1} collected at the {Upsilon}(4S) resonance, they find no significant signal and set the following branching fraction upper limits at 90% confidence level: {Beta}(B{sup 0} {yields} e{sup +}e{sup -}{gamma}) < 0.7 x 10{sup -7} and {Beta}(B{sup 0} {yields} {mu}{sup +}{mu}{sup -}{gamma}) < 3.4 x 10{sup -7}.

  6. SISGR-MuSR Investigations of Magnetic Semiconductors for Spintronics

    Office of Scientific and Technical Information (OSTI)

    Applications (Technical Report) | SciTech Connect Technical Report: SISGR-MuSR Investigations of Magnetic Semiconductors for Spintronics Applications Citation Details In-Document Search Title: SISGR-MuSR Investigations of Magnetic Semiconductors for Spintronics Applications Authors: Lichti, Roger Publication Date: 2014-03-27 OSTI Identifier: 1148701 Report Number(s): Final Report DOE Contract Number: SC0001769 Resource Type: Technical Report Research Org: Texas Tech University Sponsoring

  7. Structural insights into [mu]-opioid receptor activation (Journal Article)

    Office of Scientific and Technical Information (OSTI)

    | SciTech Connect Structural insights into [mu]-opioid receptor activation Citation Details In-Document Search Title: Structural insights into [mu]-opioid receptor activation Authors: Huang, Weijiao ; Manglik, Aashish ; Venkatakrishnan, A.J. ; Laeremans, Toon ; Feinberg, Evan N. ; Sanborn, Adrian L. ; Kato, Hideaki E. ; Livingston, Kathryn E. ; Thorsen, Thor S. ; Kling, Ralf C. ; Granier, Sébastien ; Gmeiner, Peter ; Husbands, Stephen M. ; Traynor, John R. ; Weis, William I. ; Steyaert, Jan

  8. Search for doubly-charged Higgs Boson production in the decay H++ H-- ---> mu+ mu+ mu- mu - with the D0 detector at s**(1/2) = 1.96-TeV

    SciTech Connect (OSTI)

    Zdrazil, Marian

    2004-01-01

    This work presents a search for the pair production of doubly-charged Higgs Bosons in the process p{bar p} {yields} H{sup ++}H{sup --} {yields} {mu}{sup +}{mu}{sup +}{mu}{sup -}{mu}{sup -} using inclusive dimuon events. These data correspond to an integrated luminosity of about 113 pb 1 and were recorded by the D0 experiment between August 2002 and June 2003. In the absence of a signal, 95% confidence level mass limits of M(H{sub L}{sup {+-}{+-}}) > 118.6 GeV/c{sup 2} and M(H{sub R}{sup {+-}{+-}}) > 98.1 GeV/c{sup 2} are set for left-handed and right-handed doubly-charged Higgs boson, assuming 100% branching into muons and hypercharge |Y| = 2 and Yukawa coupling h{sub {mu}{mu}} > 10{sup -7}. This is the first search for doubly-charged Higgs bosons at hadron colliders. It significantly extends the previous mass limit of 100.5 GeV/c{sup 2} for a left-handed doubly-charged Higgs boson measured in the muon final states by the OPAL collaboration.

  9. Observation of the rare $B^0_s\\to\\mu^+\\mu^-$ decay from the combined analysis of CMS and LHCb data

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Khachatryan, Vardan

    2015-05-13

    A joint measurement is presented of the branching fractions $B^0_s\\to\\mu^+\\mu^-$ and $B^0\\to\\mu^+\\mu^-$ in proton-proton collisions at the LHC by the CMS and LHCb experiments. The data samples were collected in 2011 at a centre-of-mass energy of 7 TeV, and in 2012 at 8 TeV. The combined analysis produces the first observation of the $B^0_s\\to\\mu^+\\mu^-$ decay, with a statistical significance exceeding six standard deviations, and the best measurement of its branching fraction so far, and three standard deviation evidence for the $B^0\\to\\mu^+\\mu^-$ decay. The measurements are statistically compatible with SM predictions and impose stringent constraints on several theories beyond the SM.

  10. Search for the Decays B0 to e+e-gamma and B0 to mu+mu-gamma

    SciTech Connect (OSTI)

    Kim, H

    2007-06-22

    We present results of a search for the decays B{sup 0} {yields} {ell}{sup +}{ell}{sup -}{gamma} ({ell} = e, {mu}). The search is performed using 320x106 B{bar B} pairs collected at the {Gamma}(4S) resonance with the BABAR detector at the PEP-II B Factory at SLAC. We find no significant signal and set the following branching fraction upper limits at the 90% confidence level: {beta}(B{sup 0} {yields} e{sup +}e{sup -}{gamma}) < 1.2 x 10{sup -7} and {beta}(B{sup 0} {yields} {mu}{sup +}{mu}{sup -}{gamma}) < 1.5 x 10{sup -7}.

  11. Research and Development for the Mu2e extinction Monitor

    SciTech Connect (OSTI)

    Mott, Casey Benjamin

    2016-01-01

    Mu2e is a planned experiment to search for flavor violating conversion from a muon to an electron. The experiment will use a pulsed 8 GeV proton beam to produce muons which will then stop in an aluminum target. Mu2e will search for the $\\mu^- + Al \\rightarrow e^- + Al$ process. For Mu2e, an extinction rate of 10$^{-10}$ is required to reduce the backgrounds to an acceptable level. Extinction is the ratio of the amount of protons striking the production target between beam pulses to the number striking it during the beam pulse. One of the backgrounds, off-target interactions, was simulated using G4beamline and Fermilab's Grid setup to confirm that an extinction rate of 10$^{-10}$ is possible. The extinction level will be measured by the extinction monitor which will include scintillation counters read out by photomultiplier tubes. In order to build a beam time profile, low fake responses (after pulses) are needed in the photomultiplier tubes. This thesis determines the best co mbination of resistors, voltage, and other components that provide the lowest after pulse rate.

  12. Alkane functionalization at ([mu]-Oxo)diiron(III) centers

    SciTech Connect (OSTI)

    Leising, R.A.; Kim, J.; Perez, M.A.; Que, L. Jr. )

    1993-10-20

    The reactivity of ([mu]-oxo)diferric complexes with [sup t]BuOOH (TBHP) for the functionalization of alkanes in CH[sub 3]CN has been investigated as part of our efforts to model dinuclear sites in nonheme iron enzymes. [Fe[sub 2](TPA)[sub 2]O(OAc)](CIO[sub 4])[sub 3] (1) (TPA = tris(2-pyridylmethyl)amine, OAc = acetate) is an efficient catalyst for cyclohexane oxidation, affording cyclohexanol (A, 9 equiv), cyclohexanone (K, 11 equiv), and (tert-butylperoxy)cyclohexane (P, 16 equiv) in 0.25 h at ambient temperature and pressure under an argon atmosphere. The catalyst is remarkably robust, as indicated by the [sup 1]H NMR and UV-vis spectra of the reaction mixture during the catalytic reaction and by its ability to maintain its turnover efficiency with subsequent additions of oxidant. The catalytic mechanism for TBHP utilization was explored by observing the effects of varying the tripodal ligands on the ([mu]-oxo)([mu]-carboxylato)diferric catalysts and varying the bridge on Fe[sub 2]O(TPA)[sub 2] catalysts. The (A + K)/P ratio increased as the ligands became more electron donating. Solvent also played an important role in determining the partitioning of products between A + K and P, with benzonitrile favoring hydroxylated products at the expense of P and pyridine having the opposite effect. 49 refs., 2 figs., 3 tabs.

  13. Crystal structure of the[mu]-opioid receptor bound to a morphinan...

    Office of Scientific and Technical Information (OSTI)

    receptor (mu-OR) in the central nervous system. Here we describe the 2.8 angstrom crystal structure of the mouse mu-OR in complex with an irreversible morphinan antagonist. ...

  14. On the model discriminating power of mu to e conversion in nuclei...

    Office of Scientific and Technical Information (OSTI)

    On the model discriminating power of mu to e conversion in nuclei Citation Details In-Document Search Title: On the model discriminating power of mu to e conversion in nuclei ...

  15. On the model discriminating power of mu to e conversion in nuclei...

    Office of Scientific and Technical Information (OSTI)

    On the model discriminating power of mu to e conversion in nuclei Citation Details In-Document Search Title: On the model discriminating power of mu to e conversion in nuclei...

  16. Solenoid Magnet System for the Fermilab Mu2e Experiment

    SciTech Connect (OSTI)

    Lamm, M. J.; Andreev, N.; Ambrosio, G.; Brandt, J.; Coleman, R.; Evbota, D.; Kashikhin, V. V.; Lopes, M.; Miller, J.; Nicol, T.; Ostojic, R.; Page, T.; Peterson, T.; Popp, J.; Pronskikh, V.; Tang, Z.; Tartaglia, M.; Wake, M.; Wands, R.; Yamada, R.

    2011-12-14

    The Fermilab Mu2e experiment seeks to measure the rare process of direct muon to electron conversion in the field of a nucleus. Key to the design of the experiment is a system of three superconducting solenoids; a muon production solenoid (PS) which is a 1.8 m aperture axially graded solenoid with a peak field of 5 T used to focus secondary pions and muons from a production target located in the solenoid aperture; an 'S shaped' transport solenoid (TS) which selects and transports the subsequent muons towards a stopping target; a detector solenoid (DS) which is an axially graded solenoid at the upstream end to focus transported muons to a stopping target, and a spectrometer solenoid at the downstream end to accurately measure the momentum of the outgoing conversion elections. The magnetic field requirements, the significant magnetic coupling between the solenoids, the curved muon transport geometry and the large beam induced energy deposition into the superconducting coils pose significant challenges to the magnetic, mechanical, and thermal design of this system. In this paper a conceptual design for the magnetic system which meets the Mu2e experiment requirements is presented.

  17. Solenoid Magnet System for the Fermilab Mu2e Experiment

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Lamm, M. J.; Andreev, N.; Ambrosio, G.; Brandt, J.; Coleman, R.; Evbota, D.; Kashikhin, V. V.; Lopes, M.; Miller, J.; Nicol, T.; et al

    2011-12-14

    The Fermilab Mu2e experiment seeks to measure the rare process of direct muon to electron conversion in the field of a nucleus. Key to the design of the experiment is a system of three superconducting solenoids; a muon production solenoid (PS) which is a 1.8 m aperture axially graded solenoid with a peak field of 5 T used to focus secondary pions and muons from a production target located in the solenoid aperture; an 'S shaped' transport solenoid (TS) which selects and transports the subsequent muons towards a stopping target; a detector solenoid (DS) which is an axially graded solenoidmore » at the upstream end to focus transported muons to a stopping target, and a spectrometer solenoid at the downstream end to accurately measure the momentum of the outgoing conversion elections. The magnetic field requirements, the significant magnetic coupling between the solenoids, the curved muon transport geometry and the large beam induced energy deposition into the superconducting coils pose significant challenges to the magnetic, mechanical, and thermal design of this system. In this paper a conceptual design for the magnetic system which meets the Mu2e experiment requirements is presented.« less

  18. A Combination of CDF and D0 limits on the branching ratio of B0(s)(d) ---> mu+ mu- decays

    SciTech Connect (OSTI)

    Bernhard, R.; Glenzinski, D.; Herndon, M.; Kamon, T.; Krutelyov, V.; Landsberg, G.; Lehner, F.; Lin, C.J.; Mrenna, S.; /Zurich U. /Fermilab /Wisconsin U., Madison /Texas A-M /Brown U.

    2005-08-01

    The authors combine the results of CDF and D0 searches for the rare decays B{sub s}{sup 0} {yields} {mu}{sup +}{mu}{sup -} and B{sub d}{sup 0} {yields} {mu}{sup +}{mu}{sup -}. The experiments use 364 pb{sup -1} and 300 pb{sup -1} of data respectively. The limits on the branching ratios are obtained by normalizing the estimated sensitivity to the decay B{sup +} {yields} J/{psi}K{sup +} taking into account the fragmentation ratios f{sub u}/f{sub s(d)}. The combined results exclude branching ratios of BR(B{sub s}{sup 0} {yields} {mu}{sup +}{mu}{sup -}) > 1.5 x 10{sup -7} and BR(B{sub d}{sup 0} {yields} {mu}{sup +}{mu}{sup -}) > 4.0 x 10{sup -8} at 95% confidence level. These are the most stringent limits on these decays at the present time.

  19. Mu2e production solenoid cryostat conceptual design

    SciTech Connect (OSTI)

    Nicol, T.H.; Kashikhin, V.V.; Page, T.M.; Peterson, T.J.; /Fermilab

    2011-06-01

    Mu2e is a muon-to-electron conversion experiment being designed by an international collaboration of more than 65 scientists and engineers from more than 20 research institutions for installation at Fermilab. The experiment is comprised of three large superconducting solenoid magnet systems, production solenoid (PS), transport solenoid (TS) and detector solenoid (DS). A 25 kW, 8 GeV proton beam strikes a target located in the PS creating muons from the decay of secondary particles. These muons are then focused in the PS and the resultant muon beam is transported through the TS towards the DS. The production solenoid presents a unique set of design challenges as the result of high radiation doses, stringent magnetic field requirements, and large structural forces. This paper describes the conceptual design of the PS cryostat and will include discussions of the vacuum vessel, thermal shield, multi-layer insulation, cooling system, cryogenic piping, and suspension system.

  20. Mu2e transport solenoid prototype tests results

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Lopes, Mauricio L.; G. Ambrosio; DiMarco, J.; Evbota, D.; Feher, S.; Friedsam, H.; Galt, A.; Hays, S.; Hocker, J.; Kim, M. J.; et al

    2016-02-08

    The Fermilab Mu2e experiment has been developed to search for evidence of charged lepton flavor violation through the direct conversion of muons into electrons. The transport solenoid is an s-shaped magnet which guides the muons from the source to the stopping target. It consists of fifty-two superconducting coils arranged in twenty-seven coil modules. A full-size prototype coil module, with all the features of a typical module of the full assembly, was successfully manufactured by a collaboration between INFN-Genoa and Fermilab. The prototype contains two coils that can be powered independently. In order to validate the design, the magnet went throughmore » an extensive test campaign. Warm tests included magnetic measurements with a vibrating stretched wire, electrical and dimensional checks. As a result, the cold performance was evaluated by a series of power tests as well as temperature dependence and minimum quench energy studies.« less

  1. FinalReport-DOE BES DMSE-UNR-QLi

    SciTech Connect (OSTI)

    Li, Qizhen

    2014-05-06

    The primary goal of this project is to explore the fundamental deformation and failure mechanisms for magnesium with a hexagonal close packed (HCP) crystal structure. It is critical to perform this project for a number of reasons. First, magnesium is the lightest structural metal and its application in various structural components can save the final component weight. Second, the weight reduction from the usage of magnesium-based structural components in transportation vehicles such as automobiles and aircrafts can improve fuel efficiency and reduce the greenhouse gas emissions. Third, structural components often experience dynamic loading such as cyclic loading conditions. Fourth, magnesium with a HCP crystal structure generally has its special deformation responses under loading conditions. This project investigated magnesium based materials (magnesium single crystal, pure polycrystalline magnesium, and some magnesium alloys) under various loading conditions, and also explored some processing routes to manipulate the microstructure and mechanical properties of magnesium. The research results were published in a number of articles and also disseminated through presentations in various conferences such as TMS annual meetings, MRS meetings, the international Plasticity conferences, the Pacific Rim International Congress on Advanced Materials and Processing, and AeroMat. In addition to the contribution to the research/academic community, this project is also beneficial to the general public. With the actual usage of magnesium in the passenger cars, the weight reduction and fuel consumption reduction will save the fuel bill of individual owners.

  2. The electrical and mechanical properties of Au-V and Au-V{sub...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: The electrical and mechanical properties of Au-V and Au-Vsub 2Osub 5 thin films for wear-resistant RF MEMS switches Citation Details In-Document Search Title: ...

  3. Interpretation of the first data on central Au+Au collisions...

    Office of Scientific and Technical Information (OSTI)

    production in central Au+Au collisions taken at RHIC by the PHOBOS Collaboration as well as to existing data on central Pb+Pb collisions taken at the SPS by the NA49 Collaboration. ...

  4. Tau neutrinos underground: Signals of {nu}{sub {mu}}{yields}{nu}{sub {tau}}

    Office of Scientific and Technical Information (OSTI)

    oscillations with extragalactic neutrinos (Journal Article) | SciTech Connect Tau neutrinos underground: Signals of {nu}{sub {mu}}{yields}{nu}{sub {tau}} oscillations with extragalactic neutrinos Citation Details In-Document Search Title: Tau neutrinos underground: Signals of {nu}{sub {mu}}{yields}{nu}{sub {tau}} oscillations with extragalactic neutrinos The appearance of high energy tau neutrinos due to {nu}{sub {mu}}{yields}{nu}{sub {tau}} oscillations of extragalactic neutrinos can be

  5. Rationalization of Au concentration and distribution in AuNi@Pt core-shell

    Office of Scientific and Technical Information (OSTI)

    nanoparticles for oxygen reduction reaction (Journal Article) | SciTech Connect Rationalization of Au concentration and distribution in AuNi@Pt core-shell nanoparticles for oxygen reduction reaction Citation Details In-Document Search This content will become publicly available on September 18, 2016 Title: Rationalization of Au concentration and distribution in AuNi@Pt core-shell nanoparticles for oxygen reduction reaction Improving the activity and stability of Pt-based core-shell

  6. Thermal design of the Mu2e detector solenoid

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Dhanaraj, N.; Wands, R.; Buehler, M.; Feher, S.; Page, T.; Peterson, T.; Schmitt, R.

    2014-12-18

    The reference design for a superconducting detector solenoid (DS) for the Mu2e experiment has been completed. In this study, the main functions of the DS are to provide a graded field in the region of the stopping target, which ranges from 2 to 1 T and a uniform precision magnetic field of 1 T in a volume large enough to house a tracker downstream of the stopping target. The inner diameter of the magnet cryostat is 1.9 m and the length is 10.9 m. The gradient section of the magnet is about 4 m long and the spectrometer section withmore » a uniform magnetic field is about 6 m long. The inner cryostat wall supports the stopping target, tracker, calorimeter and other equipment installed in the DS. This warm bore volume is under vacuum during operation. It is sealed on one end by the muon beam stop, while it is open on the other end where it interfaces with the Transport Solenoid. The operating temperature of the magnetic coil is 4.7 K and is indirectly cooled with helium flowing in a thermosiphon cooling scheme. This paper describes the thermal design of the solenoid, including the design aspects of the thermosiphon for the coil cooling, forced flow cooling of the thermal shields with 2 phase LN2 (Liquid Nitrogen) and the transient studies of the cool down of the cold mass as well.« less

  7. Thermal Design of the Mu2e Detector Solenoid

    SciTech Connect (OSTI)

    Dhanaraj, N.; Wands, R.; Buehler, M.; Feher, S.; Page, T.; Peterson, T.; Schmitt, R.

    2014-12-18

    The reference design for a superconducting Detector Solenoid (DS) for the Mu2e experiment has been completed. The main functions of the DS are to provide a graded field in the region of the stopping target which ranges from 2 T to 1 T and a uniform precision magnetic field of 1 T in a volume large enough to house a tracker downstream of the stopping target. The inner diameter of the magnet cryostat is 1.9 m and the length is 10.9 m. The gradient section of the magnet is about 4 m long and the spectrometer section with a uniform magnetic field is about 6 m long. The inner cryostat wall supports the stopping target, tracker, calorimeter and other equipment installed in the DS. This warm bore volume is under vacuum during operation. It is sealed on one end by the muon beam stop, while it is open on the other end where it interfaces with the Transport Solenoid. The operating temperature of the magnetic coil is 4.7 K and is indirectly cooled with helium flowing in a thermosiphon cooling scheme. This paper describes the thermal design of the solenoid, including the design aspects of the thermosiphon for the coil cooling, forced flow cooling of the thermal shields with 2 phase LN2 (Liquid Nitrogen) and the transient studies of the cool down of the cold mass as well.

  8. Thermal Design of the Mu2e Detector Solenoid

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Dhanaraj, N.; Wands, R.; Buehler, M.; Feher, S.; Page, T.; Peterson, T.; Schmitt, R.

    2014-12-18

    The reference design for a superconducting Detector Solenoid (DS) for the Mu2e experiment has been completed. The main functions of the DS are to provide a graded field in the region of the stopping target which ranges from 2 T to 1 T and a uniform precision magnetic field of 1 T in a volume large enough to house a tracker downstream of the stopping target. The inner diameter of the magnet cryostat is 1.9 m and the length is 10.9 m. The gradient section of the magnet is about 4 m long and the spectrometer section with a uniformmoremagnetic field is about 6 m long. The inner cryostat wall supports the stopping target, tracker, calorimeter and other equipment installed in the DS. This warm bore volume is under vacuum during operation. It is sealed on one end by the muon beam stop, while it is open on the other end where it interfaces with the Transport Solenoid. The operating temperature of the magnetic coil is 4.7 K and is indirectly cooled with helium flowing in a thermosiphon cooling scheme. This paper describes the thermal design of the solenoid, including the design aspects of the thermosiphon for the coil cooling, forced flow cooling of the thermal shields with 2 phase LN2 (Liquid Nitrogen) and the transient studies of the cool down of the cold mass as well.less

  9. Calculation of resonances in a dt{mu} molecule by the R-matrix method

    SciTech Connect (OSTI)

    Mil'nikov, Gennady V.; Nakamura, Hiroki

    2003-03-01

    Using the spectral representation of Green's function, we calculate the density of states and extract parameters of resonances in the scattering system. The method is implemented for the resonances in the dt{mu} molecule below the t{mu} (n=2) threshold.

  10. Au-Pt heteroaggregate dendritic nanostructures and Au-Pt alloy nanoparticles and their use as catalysts

    DOE Patents [OSTI]

    Eichhorn, Bryan W.; Zhou, Shenghu; Jackson, Gregory Scott

    2011-10-18

    Au--Pt heteroaggregate dendritic nanostructures and AuPt alloy nanoparticles, and their use as anodic catalysts in fuel cells.

  11. Evidence for Low-Intensity D-D Reaction as a Result of Exothermic Deuterium Desorption from Au/Pd/PdO:D Heterostructure

    SciTech Connect (OSTI)

    Lipson, A.G.; Lyakhov, B.F.; Roussetski, A.S.; Akimoto, T.; Mizuno, T.; Asami, N.; Shimada, R.; Miyashita, S.; Takahashi, A.

    2000-09-15

    Low-intensity nuclear emissions (neutrons and charged particles) due to exothermic deuterium desorption from Au/Pd/PdO heterostructure loaded with deuterium by electrolysis have been studied by NE213 neutron detection as well as SSB and CR-39 charged-particle detectors in low-background conditions with large statistics. Similar measurements were performed with the Au/Pd/PdO:H heterostructure as a control. It has been established that in experiments with the Au/Pd/PdO:D system, the excessive 2.45-MeV neutrons and 3.0-MeV protons are better detected than with the Au/Pd/PdO:H system, where those detection rates for n and p did not exceed the cosmic background level. The levels of neutron and proton emissions for 40- to 60-{mu}m-thick samples are found to be close to one another and after subtracting background (Au/Pd/PdO:H count rate) consist of I{sub n} = (19 {+-} 2).10{sup -3} n/s and I{sub p} (4.0 {+-} 1.0).10{sup -3} p/s in a 4{pi} solid angle, respectively. These yields of D-D reaction products in Au/Pd/PdO heterostructure comply with the mean D-D reaction rate of {lambda}{sub dd} {approx} 10{sup -23}s{sup -1} per D-D pair.

  12. RHIC Au beam in Run 2014

    SciTech Connect (OSTI)

    Zhang, S. Y.

    2014-09-15

    Au beam at the RHIC ramp in run 2014 is reviewed together with the run 2011 and run 2012. Observed bunch length and longitudinal emittance are compared with the IBS simulations. The IBS growth rate of the longitudinal emittance in run 2014 is similar to run 2011, and both are larger than run 2012. This is explained by the large transverse emittance at high intensity observed in run 2012, but not in run 2014. The big improvement of the AGS ramping in run 2014 might be related to this change. The importance of the injector intensity improvement in run 2014 is emphasized, which gives rise to the initial luminosity improvement of 50% in run 2014, compared with the previous Au-Au run 2011. In addition, a modified IBS model, which is calibrated using the RHIC Au runs from 9.8 GeV/n to 100 GeV/n, is presented and used in the study.

  13. The MuCap Experiment (Journal Article) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    The MuCap Experiment Citation Details In-Document Search Title: The MuCap Experiment Muon capture on the proton is sensitive to the weak pseudoscalar form factor, g{sub p}, one of the basic parameters characterizing the nucleon electroweak charged-current interaction. There is a precise theoretical prediction for g{sub p} based on chiral symmetry of QCD, yet the results of past experiments are controversial: they are dependent on a poorly-known, mu-molecular kinetic parameter, and there is no

  14. DFT study on cysteine adsorption mechanism on Au(111) and Au(110)

    SciTech Connect (OSTI)

    Buimaga-Iarinca, Luiza; Floare, Calin G.; Calborean, Adrian; Turcu, Ioan

    2013-11-13

    Periodic density functional theory calculations were used to investigate relevant aspects of adsorption mechanisms of cysteine dimers in protonated form on Au(111) and Au(110) surfaces. The projected densities of states are explicitly discussed for all main chemical groups of cysteine, i.e. the amino group (NH2), the thiol group (SH) and the carboxylic group (COOH) to identify differences in adsorption mechanism. Special emphasis is put on the analysis of changes in the electronic structure of molecules adsorbed on Au(111) and Au(110) surfaces as well as the accompanying charge transfer mechanisms at molecule-substrate interaction.

  15. Lepton flavor violating Higgs bosons and {tau}{yields}{mu}{gamma}

    SciTech Connect (OSTI)

    Davidson, Sacha; Grenier, Gerald

    2010-05-01

    We update phenomenological constraints on a two Higgs doublet model with lepton flavor nonconserving Yukawa couplings. We review that tan{beta} is ambiguous in such 'type III' models, and define it from the {tau} Yukawa coupling. The neutral scalars {phi} could be searched for at hadron colliders in {phi}{yields}{tau}{mu} and are constrained by the rare decay {tau}{yields}{mu}{gamma}. The Feynman diagrams for the collider process, with Higgs production via gluon fusion, are similar to the two-loop ''Barr-Zee'' diagrams, which contribute to {tau}{yields}{mu}{gamma}. Some ''tuning'' is required to obtain a collider cross section of order the standard model expectation for {sigma}(gg{yields}h{sub SM{yields}{tau}}{sup +{tau}-}), while agreeing with the current bound from {tau}{yields}{mu}{gamma}.

  16. Crystal structure of the[mu]-opioid receptor bound to a morphinan

    Office of Scientific and Technical Information (OSTI)

    antagonist (Journal Article) | SciTech Connect Crystal structure of the[mu]-opioid receptor bound to a morphinan antagonist Citation Details In-Document Search Title: Crystal structure of the[mu]-opioid receptor bound to a morphinan antagonist Opium is one of the world's oldest drugs, and its derivatives morphine and codeine are among the most used clinical drugs to relieve severe pain. These prototypical opioids produce analgesia as well as many undesirable side effects (sedation, apnoea

  17. Synthesis and characterization in AuCu–Si nanostructures

    SciTech Connect (OSTI)

    Novelo, T.E.; Amézaga-Madrid, P.; Maldonado, R.D.; Oliva, A.I.; Alonzo-Medina, G.M.

    2015-03-15

    Au/Cu bilayers with different Au:Cu concentrations (25:75, 50:50 and 75:25 at.%) were deposited on Si(100) substrates by thermal evaporation. The thicknesses of all Au/Cu bilayers were 150 nm. The alloys were prepared by thermal diffusion into a vacuum oven with argon atmosphere at 690 K during 1 h. X-ray diffraction analysis revealed different phases of AuCu and CuSi alloys in the samples after annealing process. CuSi alloys were mainly obtained for 25:75 at.% samples, meanwhile the AuCuII phase dominates for samples prepared with 50:50 at.%. Additionally, the Au:Cu alloys with 75:25 at.%, produce Au{sub 2}Cu{sub 3} and Au{sub 3}Cu phases. The formed alloys were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS) to study the morphology and the elemental concentration of the formed alloys. - Highlights: • AuCu/Si alloy thin films were prepared by thermal diffusion. • Alloys prepared with 50 at.% of Au produce the AuCuII phase. • Alloys prepared with 75 at.% of Au produce Au{sub 3}Cu and Au{sub 2}Cu{sub 3} phases. • All alloys present diffusion of Si and Cu through the CuSi alloy formation.

  18. ORIGIN OF 12 {mu}m EMISSION ACROSS GALAXY POPULATIONS FROM WISE AND SDSS SURVEYS

    SciTech Connect (OSTI)

    Donoso, E.; Yan Lin; Tsai, C.; Eisenhardt, P.; Stern, D.; Assef, R. J.; Leisawitz, D.; Jarrett, T. H.; Stanford, S. A.

    2012-04-01

    We cross-matched Wide-field Infrared Survey Explorer sources brighter than 1 mJy at 12 {mu}m with the Sloan Digital Sky Survey galaxy spectroscopic catalog to produce a sample of {approx}10{sup 5} galaxies at (z) = 0.08, the largest of its kind. This sample is dominated (70%) by star-forming (SF) galaxies from the blue sequence, with total IR luminosities in the range {approx}10{sup 8}-10{sup 12} L{sub Sun }. We identify which stellar populations are responsible for most of the 12 {mu}m emission. We find that most ({approx}80%) of the 12 {mu}m emission in SF galaxies is produced by stellar populations younger than 0.6 Gyr. In contrast, the 12 {mu}m emission in weak active galactic nuclei (AGNs; L{sub [Oiii]} < 10{sup 7} L{sub .}) is produced by older stars, with ages of {approx}1-3 Gyr. We find that L{sub 12{mu}m} linearly correlates with stellar mass for SF galaxies. At fixed 12 {mu}m luminosity, weak AGNs deviate toward higher masses since they tend to be hosted by massive, early-type galaxies with older stellar populations. SF galaxies and weak AGNs follow different L{sub 12{mu}m}-SFR (star formation rate) relations, with weak AGNs showing excess 12 {mu}m emission at low SFR (0.02-1 M{sub Sun} yr{sup -1}). This is likely due to dust grains heated by older stars. While the specific star formation rate (SSFR) of SF galaxies is nearly constant, the SSFR of weak AGNs decreases by {approx}3 orders of magnitude, reflecting the very different star formation efficiencies between SF galaxies and massive, early-type galaxies. Stronger type II AGNs in our sample (L[{sub Oiii]} > 10{sup 7} L{sub .}), act as an extension of massive SF galaxies, connecting the SF and weak AGN sequences. This suggests a picture where galaxies form stars normally until an AGN (possibly after a starburst episode) starts to gradually quench the SF activity. We also find that 4.6-12 {mu}m color is a useful first-order indicator of SF activity in a galaxy when no other data are available.

  19. Suppression of Upsilon production in d + Au and Au + Au collisions at root s(NN) = 200 GeV (vol 735, pg 127, 2014)

    SciTech Connect (OSTI)

    Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alekseev, I.; Alford, J.; Anson, C. D.; Aparin, A.; Arkhipkin, D.; Gliske, S.; Krueger, K.; Spinka, H. M.; Underwood, D.G.

    2014-07-30

    We report measurements of ? meson production in p + p, d +Au, and Au+Aucollisions using the STAR detector at RHIC. We compare the ? yield to the measured cross section in p + p collisions in order to quantify any modifications of the yield in cold nuclear matter using d +Au data and in hot nuclear matter using Au+Au data separated into three centrality classes. Our p +p measurement is based on three times the statistics of our previous result. We obtain a nuclear modification factor for ? (1S + 2S + 3S) in the rapidity range |y| < 1 in d + Aucollisions of RdAu = 0.79 0.24(stat.) 0.03(syst.) 0.10(p + p syst.). A comparison with models including shadowing and initial state parton energy loss indicates the presence of additional cold-nuclear matter suppression. Similarly, in the top 10% most-central Au + Au collisions, we measure a nuclear modification factor of R AA = 0.49 0.1(stat.) 0.02(syst.) 0.06(p + p syst.), which is a larger suppression factor than that seen in cold nuclear matter. Our results are consistent with complete suppression of excited-state ? mesons in Au + Aucollisions. The additional suppression in Au + Au is consistent with the level expected in model calculations that include the presence of a hot, deconfined QuarkGluon Plasma. However, understanding the suppression seen in d + Au is still needed before any definitive statements about the nature of the suppression in Au + Au can be made.

  20. mu-Scale Variations Of Elemental Composition In Individual Atmospheric Particles By Means Of Synchrotron Radiation Based mu-XRF Analysis

    SciTech Connect (OSTI)

    Schleicher, N.; Kramar, U.; Norra, S.; Dietze, V.; Kaminski, U.; Cen, K.; Yu, Y.

    2010-04-06

    Atmospheric pollution poses a huge challenge especially for densely populated urban areas. Although a tremendous knowledge already exists on atmospheric particulate pollution, only very limited knowledge is available on mineral and chemical composition of single atmospheric particles because most studies on air pollution focus on total mass concentrations or bulk elemental analysis. However, it is of particular importance to investigate the properties of single particles since according to their individually composition they differ in their specific impact on climate change, negative environment and health effects, as well as accelerating the weathering of stone buildings in urban areas. Particles with sulfate and nitrate coatings together with sufficient moisture increase metal solubility and possibly catalyze further surface reactions on stone facades of buildings. From the viewpoint of health effects of aerosols it is important to consider agglomerations processes of fine anthropogenic and highly toxic particles with coarse geogenic and less toxic particles. With respect to fundamental research in mineralogy, processes forming composed coarse particles consisting of geogenic and anthropogenic substances are valuable to study since a new type of particle is produced. In this context, the important and still in detail unknown role of geogenic particles as catchers for anthropogenic aerosols can be investigated more closely. Coarse particles can provide a possible sink for fine particles. Moreover, the intermixture of particles from geogenic and anthropogenic sources and the spatial and temporal variations of contributions from different sources, which plays a decisive role in the study area of Beijing, can be clarified with this approach. For this study, particles were collected with the passive sampling device Sigma-2 and analyzed for particles from 3 to 96 {mu}m. The analyzed particles showed a very inhomogeneous distribution in their elemental composition. For this study, synchrotron radiation based mu-X-ray fluorescence analysis (mu-SXRF) proved to be an excellent tool to investigate mu-scalic distributions of main and trace element concentrations within individual airborne particles.

  1. The Mu2e crystal calorimeter and improvements in the $\\mu^-\\mbox{N} \\to e^-\\mbox{N}$ search sensitivity

    SciTech Connect (OSTI)

    Pezzullo, Gianantonio

    2016-01-01

    The Mu2e experiment will search for Charged Lepton Flavor Violation (CLFV) looking at the conversion of a muon into an electron in the field of an aluminum nucleus. About $7\\cdot 10^{17}$ muons, provided by a dedicated muon beam line in construction at the Fermi National Accelarator Laboratory (Fermilab), will be stopped in 3 years in the Aluminum target. The corresponding single event sensitivity will be $2.5\\cdot 10^{-17}$. The Standard Model of particle physics, even extendend to include the finite neutrino masses, predicts the ratio \\convrate between muon conversions and muon nuclear captures to be $\\sim 10^{- 52}$. Several extensions of the Standard Model predict \\convrate to be in the range of $10^{-14} - 10^{-18}$. % The current best experimental limit, set by the SINDRUM II experiment is $7 \\cdot 10^{-13}$ @ $90\\%$ CL. The Mu2e experiment plans to improve this experimental limit by four order of magnitude to test many of the possible extensions of the Standard Model. To reach this ambitious goal, the Mu2e experiment is expected to use an intense pulsed muon beam, and rely on a detector system composed of a straw tube tracker and a calorimeter made of pure CsI crystals. The calorimeter plays a central role in the Mu2e measurement, providing particle identification capabilities that are necessary for rejecting two of the most dangerous background sources that can mimic the \\muconv conversion electron: cosmic muons and $\\bar{p}$ induced background. The calorimeter information allows also to improve the tracking performance. Thanks to a calorimeter-seeded track finder algorithm, it is possible to increase the track reconstruction efficiency, and make it more robust with respect to the occupancy level. Expected performances of the calorimeter have been studied in a beam test at the Beam Test Facility in Frascati (Rome, Italy). A reduced scale calorimeter prototype has been exposed to an electron beam, with energy varying from 80 to 140 MeV, f or measuring the timing resolution and validate the Monte Carlo prediction. A timing resolution $\\sigma_{\\rm t}<200$ ps @ 100 MeV has been obtained. Combination of the background rejection performance, and the improvements in the track reconstruction, have then been used in the calculation of the expected Mu2e sensitivity.

  2. Search for High-Mass Resonances Decaying into Leptons of Different Flavor (e mu, e tau, mu tau) in p anti-p Collisions at sqrt(s) = 1.96 TeV

    SciTech Connect (OSTI)

    Tu, Yanjun; /Pennsylvania U.

    2008-10-01

    We present a search for high-mass resonances decaying into two leptons of different flavor: e{mu}, e{tau}, and {mu}{tau}. These resonances are predicted by several models beyond the standard model, such as the R-parity-violating MSSM. The search is based on 1 fb{sup -1} of data collected at the Collider Detector at Fermilab (CDF II) in proton anti-proton collisions. Our observations are consistent with the standard model expectations. The results are interpreted to set 95% C.L. upper limits on {sigma} x BR of {tilde {nu}}{sub {tau}} {yields} e{mu}, e{tau}, {mu}{tau}.

  3. Optimization of AC Dipole Parameters for the Mu2e Extinction System

    SciTech Connect (OSTI)

    Prebys, E.; /Fermilab

    2012-05-01

    The Mu2e experiment is being planned at Fermilab to measure the rate for muons to convert to electrons in the field of an atomic nucleus with unprecedented precision. This experiment uses an 8 GeV primary proton beam consisting of short ({approx}200 nsec FW) bunches, separated by 1.7 {mu}sec. It is vital that out-of-bunch beam be suppressed at the level of 10{sup -10} or less. This poster describes the parametric analysis which was done to determine the optimum harmonics and magnet specifications for this system, as well as the implications for the beam line optics.

  4. Optimization of the muon stopping target for the MU2E collaboration

    SciTech Connect (OSTI)

    Hodge, Zachary Donovan

    2013-01-01

    The Mu2e Experiment utilizes state of the art accelerators, superconducting magnets, detectors, electronics, and other equipment to maximize the sensitivity to such a rare process. Many of the components of the Mu2e hardware are critical to the overall physics capability of the experiment. The muon stopping target, where muons are stopped and may interact via this very rare process, is one such component where any improvements beyond the base design can have a significant impact on the experiment. This thesis explores possible modifications to the geometry of the muon stopping target. The goal is to determine if any modifications can improve the sensitivity of observing the muon conversion process.

  5. From the ternary Eu(Au/In)2 and EuAu4(Au/In)2 with remarkable Au/In distributions to a new structure type: The gold-rich Eu5Au16(Au/In)6 structure

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Steinberg, Simon; Card, Nathan; Mudring, Anja -Verena

    2015-08-13

    The ternary Eu(Au/In)2 (EuAu0.46In1.54(2)) (I), EuAu4(Au/In)2 (EuAu4+xIn2–x with x = 0.75(2) (II), 0.93(2), and 1.03(2)), and Eu5Au16(Au/In)6 (Eu5Au17.29In4.71(3)) (III) have been synthesized, and their structures were characterized by single-crystal X-ray diffraction. I and II crystallize with the CeCu2-type (Pearson Symbol oI12; Imma; Z = 4; a = 4.9018(4) Å; b = 7.8237(5) Å; c = 8.4457(5) Å) and the YbAl4Mo2-type (tI14; I4/mmm; Z = 2; a = 7.1612(7) Å; c = 5.5268(7) Å) and exhibit significant Au/In disorder. I is composed of an Au/In-mixed diamond-related host lattice encapsulating Eu atoms, while the structure of II features ribbons of distorted, squaredmore » Au8 prisms enclosing Eu, Au, and In atoms. Combination of these structural motifs leads to a new structure type as observed for Eu5Au16(Au/In)6 (Eu5Au17.29In4.71(3)) (oS108; Cmcm; Z = 4; a = 7.2283(4) Å; b = 9.0499(6) Å; c = 34.619(2) Å), which formally represents a one-dimensional intergrowth of the series EuAu2–“EuAu4In2”. The site preferences of the disordered Au/In positions in II were investigated for different hypothetical “EuAu4(Au/In)2” models using the projector-augmented wave method and indicate that these structures attempt to optimize the frequencies of the heteroatomic Au–In contacts. Furthermore, a chemical bonding analysis on two “EuAu5In” and “EuAu4In2” models employed the TB-LMTO-ASA method and reveals that the subtle interplay between the local atomic environments and the bond energies determines the structural and site preferences for these systems.« less

  6. Synthesis, structure, and bonding in K12Au21Sn4. A polar intermetallic compound with dense Au20 and open AuSn4 layers

    SciTech Connect (OSTI)

    Li, Bin; Kim, Sung-Jin; Miller, Gordon J.; and Corbett, John D.

    2009-10-29

    The new phase K{sub 12}Au{sub 21}Sn{sub 4} has been synthesized by direct reaction of the elements at elevated temperatures. Single crystal X-ray diffraction established its orthorhombic structure, space group Pmmn (No. 59), a = 12.162(2); b = 18.058(4); c = 8.657(2) {angstrom}, V = 1901.3(7) {angstrom}{sup 3}, and Z = 2. The structure consists of infinite puckered sheets of vertex-sharing gold tetrahedra (Au{sub 20}) that are tied together by thin layers of alternating four-bonded-Sn and -Au atoms (AuSn{sub 4}). Remarkably, the dense but electron-poorer blocks of Au tetrahedra coexist with more open and saturated Au-Sn layers, which are fragments of a zinc blende type structure that maximize tetrahedral heteroatomic bonding outside of the network of gold tetrahedra. LMTO band structure calculations reveal metallic properties and a pseudogap at 256 valence electrons per formula unit, only three electrons fewer than in the title compound and at a point at which strong Au-Sn bonding is optimized. Additionally, the tight coordination of the Au framework atoms by K plays an important bonding role: each Au tetrahedra has 10 K neighbors and each K atom has 8-12 Au contacts. The appreciably different role of the p element Sn in this structure from that in the triel members in K{sub 3}Au{sub 5}In and Rb{sub 2}Au{sub 3}Tl appears to arise from its higher electron count which leads to better p-bonding (valence electron concentrations = 1.32 versus 1.22).

  7. The MuCap experiment: A measurement of the muon capture rate in hydrogen gas

    SciTech Connect (OSTI)

    Banks, T. I.

    2007-10-26

    We have recently measured the rate of nuclear muon capture by the proton, using a novel technique which involves a time projection chamber operating in ultraclean, deuterium-depleted hydrogen gas. The target's low gas density of 1% compared to liquid hydrogen is key to avoiding uncertainties that arise from the formation of muonic molecules. The capture rate from the hyperfine singlet ground state of the {mu}p atom was obtained from the difference between the {mu}{sup -} disappearance rate in hydrogen and the world average for the {mu}{sup +} decay rate, yielding {lambda}{sub S} = 725.0{+-}17.4 s{sup -1}, from which the induced pseudoscalar coupling of the nucleon, g{sub P}(q{sup 2} = 0.88m{sub {mu}}{sup 2}) = 7.3{+-}1.1, is extracted. This result is consistent with theoretical predictions for g{sub P} that are based on the approximate chiral symmetry of QCD.

  8. MARS Tracking Simulations for the Mu2e Slow Extracted Proton Beam

    SciTech Connect (OSTI)

    Nagaslaev, Vladimir; Rakhno, Igor

    2015-06-01

    Particle tracking taking into account interactions with fields and materials is necessary for proper evaluation of the resonant extraction losses and geometry optimization for the extraction beam line. This paper describes the tracking simulations for the Mu2e Resonant Extraction and discusses the geometry choices made based on these simulations.

  9. Collision-spike sputtering of Au nanoparticles

    SciTech Connect (OSTI)

    Sandoval, Luis; Urbassek, Herbert M.

    2015-08-06

    Ion irradiation of nanoparticles leads to enhanced sputter yields if the nanoparticle size is of the order of the ion penetration depth. While this feature is reasonably well understood for collision-cascade sputtering, we explore it in the regime of collision-spike sputtering using molecular-dynamics simulation. For this specific case of 200-keV Xe bombardment of Au particles, we show that collision spikes lead to abundant sputtering with an average yield of 397 ± 121 atoms compared to only 116 ± 48 atoms for a bulk Au target. Only around 31% of the impact energy remains in the nanoparticles after impact; the remainder is transported away by the transmitted projectile and the ejecta. The sputter yield of supported nanoparticles is estimated to be around 80% of that of free nanoparticles due to the suppression of forward sputtering.

  10. OPERATION OF THE RHIC AU ION SOURCE.

    SciTech Connect (OSTI)

    STESKI,D.B.; ALESSI,J.; BENJAMIN,J.; CARLSON,C.; MANNI,M.; THIEBERGER,P.; WIPLICH,M.

    2001-09-02

    The Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL) is beginning its second year of operation. A cesium sputter ion source injecting into a tandem Van de Graaff provides the gold ions for RHIC. The ion source is operated in the pulsed beam mode and produces a 500{micro}sec long pulse of Au{sup -} with a peak intensity of 290pA at the entrance of the tandem. After acceleration in the tandem and post stripping, this results in a beam of Au{sup +32} with an intensity of 80e{micro}A and an energy of 182MeV. Over the last several years, a series of improvements have been made to increase the intensity of the pulsed beam from the ion source. Details of the source performance and improvements will be presented. In addition, an effort is under way to provide other beam species for RHIC collisions.

  11. Collision-spike sputtering of Au nanoparticles

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Sandoval, Luis; Urbassek, Herbert M.

    2015-08-06

    Ion irradiation of nanoparticles leads to enhanced sputter yields if the nanoparticle size is of the order of the ion penetration depth. While this feature is reasonably well understood for collision-cascade sputtering, we explore it in the regime of collision-spike sputtering using molecular-dynamics simulation. For this specific case of 200-keV Xe bombardment of Au particles, we show that collision spikes lead to abundant sputtering with an average yield of 397 ± 121 atoms compared to only 116 ± 48 atoms for a bulk Au target. Only around 31% of the impact energy remains in the nanoparticles after impact; the remaindermore » is transported away by the transmitted projectile and the ejecta. The sputter yield of supported nanoparticles is estimated to be around 80% of that of free nanoparticles due to the suppression of forward sputtering.« less

  12. The electrical and mechanical properties of Au-V and Au-V{sub 2}O{sub 5}

    Office of Scientific and Technical Information (OSTI)

    thin films for wear-resistant RF MEMS switches (Journal Article) | SciTech Connect Journal Article: The electrical and mechanical properties of Au-V and Au-V{sub 2}O{sub 5} thin films for wear-resistant RF MEMS switches Citation Details In-Document Search Title: The electrical and mechanical properties of Au-V and Au-V{sub 2}O{sub 5} thin films for wear-resistant RF MEMS switches To explore alternatives to the use of pure Au in Ohmic contact RF microelectromechanical switches, we have

  13. Analysis of the charmed semileptonic decay D+ ---> rho0 mu+ nu

    SciTech Connect (OSTI)

    Luiggi, Eduardo E.; /Vanderbilt U.; ,

    2008-12-01

    The search for the fundamental constituents of matter has been pursued and studied since the dawn of civilization. As early as the fourth century BCE, Democritus, expanding the teachings of Leucippus, proposed small, indivisible entities called atoms, interacting with each other to form the Universe. Democritus was convinced of this by observing the environment around him. He observed, for example, how a collection of tiny grains of sand can make out smooth beaches. Today, following the lead set by Democritus more than 2500 years ago, at the heart of particle physics is the hypothesis that everything we can observe in the Universe is made of a small number of fundamental particles interacting with each other. In contrast to Democritus, for the last hundred years we have been able to perform experiments that probe deeper and deeper into matter in the search for the fundamental particles of nature. Today's knowledge is encapsulated in the Standard Model of particle physics, a model describing the fundamental particles and their interactions. It is within this model that the work in this thesis is presented. This work attempts to add to the understanding of the Standard Model by measuring the relative branching fraction of the charmed semileptonic decay D{sup +} {yields} {rho}{sup 0}{mu}{sup +}{nu} with respect to D{sup +} {yields} {bar K}*{sup 0} {mu}{sup +}{nu}. Many theoretical models that describe hadronic interactions predict the value of this relative branching fraction, but only a handful of experiments have been able to measure it with any precision. By making a precise measurement of this relative branching fraction theorists can distinguish between viable models as well as refine existing ones. In this thesis we presented the measurement of the branching fraction ratio of the Cabibbo suppressed semileptonic decay mode D{sup +} {yields} {rho}{sup 0}{mu}{sup +}{nu} with respect to the Cabibbo favored mode D{sup +} {yields} {bar K}*{sup 0} {mu}{sup +}{nu} using data collected by the FOCUS collaboration. We used a binned maximum log-likelihood fit that included all known semileptonic backgrounds as well as combinatorial and muonmisidentification backgrounds to extract the yields for both the signal and normalization modes. We reconstructed 320 {+-} 44 D{sup +} {yields} {rho}{sup 0}{mu}{sup +}{nu} events and 11372 {+-} 161 D{sup +} {yields} K{sup -}{pi}{sup +}{mu}{sup +}{nu} events. Taking into account the non-resonant contribution to the D{sup +} {yields} K{sup -}{pi}{sup +}{mu}{sup +}{nu} yield due to a s-wave interference first measured by FOCUS the branching fraction ratio is: {Lambda}(D{sup +} {yields} {rho}{sup 0}{mu}{sup +}{nu}) = 0.0412 {+-} 0.0057 {+-} 0.0040 (VII.1) where the first error is statistical and the second error is the systematic uncertainty. This represents a substantial improvement over the previous world average. More importantly, the new world average for {Lambda}(D{sup +}{yields}{rho}{sup 0}{mu}{sup +}{nu})/{Lambda}(D{sup +}{yields}{bar K}*{sup 0}{mu}{sup +}{nu}) along with the improved measurements in the electronic mode can be used to discriminate among different theoretical approaches that aim to understand the hadronic current involved in the charm to light quark decay process. The average of the electronic and muonic modes indicate that predictions for the partial decay width {Lambda}(D{sup +} {yields} {rho}{sup 0}{ell}{sup +}{nu}) and the ratio {Lambda}(D{sup +}{yields}{rho}{sup 0}{ell}{sup +}{nu})/{Lambda}(D{sup +}{yields}{bar K}*{sup 0}{ell}{sup +}{nu}) based on Sum Rules are too low. Using the same data used to extract {Lambda}(D{sup +}{yields}{rho}{sup 0}{mu}{sup +}{nu})/{Lambda}(D{sup +}{yields}{bar K}*{sup 0}{mu}{sup +}{nu}) we studied the feasibility of measuring the form factors for the D{sup +} {yields} {rho}{sup 0}{mu}{sup +}{nu} decay. We found that the need to further reduce the combinatorial and muon misidentification backgrounds left us with a much smaller sample of 52 {+-} 12 D{sup +} {yields} {rho}{sup 0}{mu}{sup +}{mu} events; not enough to make a statistically significa

  14. Simulation of Electric Field in Semi Insulating Au/CdTe/Au Detector under Flux

    SciTech Connect (OSTI)

    Franc, J.; James, R.; Grill, R.; Kubat, J.; Belas, E.; Hoschl, P.; Moravec, P.; Praus, P.

    2009-08-02

    We report our simulations on the profile of the electric field in semi insulating CdTe and CdZnTe with Au contacts under radiation flux. The type of the space charge and electric field distribution in the Au/CdTe/Au structure is at high fluxes result of a combined influence of charge formed due to band bending at the electrodes and from photo generated carriers, which are trapped at deep levels. Simultaneous solution of drift-diffusion and Poisson equations is used for the calculation. We show, that the space charge originating from trapped photo-carriers starts to dominate at fluxes 10{sup 15}-10{sup 16}cm{sup -2}s{sup -1}, when the influence of contacts starts to be negligible.

  15. MU Eneg

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    is included, but an estimated 3.0 quadrillion Btu of renewable Note 8; and Table A8. * Geothermal Energy and Other: Section 2, energy used by other sectors is not included....

  16. Out-of-Time Beam Extinction in the MU2E Experiment

    SciTech Connect (OSTI)

    Prebys, E. J.; Werkema, S.

    2015-06-01

    The Mu2e Experiment at Fermilab will search for the conversion of a muon to an electron in the field of an atomic nucleus with unprecedented sensitivity. The experiment requires a beam consisting of proton bunches 250 ns FW long, separated by 1.7 $\\mu$ sec, with no out-of-time protons at the $10^{10}$ fractional level. Satisfying this "extinction" requirement is very challenging. The formation of the bunches is expected to result in an extinction on the order of $10^5$. The remaining extinction will be accomplished by a system of resonant magnets and collimators, configured such that only in-time beam is delivered to the experiment. Our simulations show that the total extinction achievable by the system is on the order of $10^{12}$, with an efficiency for transmitting in-time beam of 99.6%.

  17. DOElAU62350-43

    Office of Legacy Management (LM)

    DOElAU62350-43 REV. 2 BASELINE RISK ASSESSMENT OF GROUND WATER CONTAMINATION AT THE MONUMENT VALLEY URANIUM MILL TAILINGS SITE CANE VALLEY, ARIZONA March 1996 INTENDED FOR PUBLIC RELEASE This report has been reproduced from the best available copy. Available in paper copy and microfiche Number of pages in this report: 160 DOE and DOE contractors can obtain copies of this report from: Office of Scientific and Technical Information P.O. Box 62 Oak Ridge, TN 37831 (61 5) 576-8401 This report is

  18. EuTZn (T=Pd, Pt, Au) with TiNiSi-type structure-Magnetic properties and {sup 151}Eu Moessbauer spectroscopy

    SciTech Connect (OSTI)

    Mishra, Trinath; Hermes, Wilfried; Harmening, Thomas; Eul, Matthias; Poettgen, Rainer

    2009-09-15

    The europium compounds EuTZn (T=Pd, Pt, Au) were synthesized from the elements in sealed tantalum tubes in an induction furnace. These intermetallics crystallize with the orthorhombic TiNiSi-type structure, space group Pnma. The structures were investigated by X-ray diffraction on powders and single crystals: a=732.3(2), b=448.5(2), c=787.7(2) pm, R{sub 1}/wR{sub 2}=0.0400/0.0594, 565 F{sup 2} values for EuPdZn, a=727.8(3), b=443.7(1), c=781.7(3) pm, R{sub 1}/wR{sub 2}=0.0605/0.0866, 573 F{sup 2} values for EuPtZn, and a=747.4(2), b=465.8(2), c=789.1(4) pm, R{sub 1}/wR{sub 2}=0.0351/0.0590, 658 F{sup 2} values for EuAuZn, with 20 variables per refinement. Together the T and zinc atoms build up three-dimensional [TZn] networks with short T-Zn distances. The EuTZn compounds show Curie-Weiss behavior in the temperature range from 75 to 300 K with mu{sub eff}=7.97(1), 7.70(1), and 7.94(1) mu{sub B}/Eu atom and theta{sub P}=18.6(1), 34.9(1), and 55.5(1) K for T=Pd, Pt, and Au, respectively, indicating divalent europium. Antiferromagntic ordering was detected at 15.1(3) K for EuPdZn and canted ferromagnetic ordering at 21.2(3) and 51.1(3) K for EuPtZn and EuAuZn. {sup 151}Eu Moessbauer spectroscopic measurements confirm the divalent nature of the europium atoms by isomer shift values ranging from -8.22(8) (EuPtZn) to -9.23(2) mm/s (EuAuZn). At 4.2 K full magnetic hyperfine field splitting is observed in all three compounds due to magnetic ordering of the europium magnetic moments. - Graphical abstract: Europium coordination in EuPdZn, EuPtZn, and EuAuZn.

  19. Radiation shielding issues for MuCool test area at Fermilab

    SciTech Connect (OSTI)

    Rakhno, I.; Johnstone, C.; /Fermilab

    2005-03-01

    The MuCool Test Area (MTA) is an intense primary beam facility derived directly from the Fermilab Linac to test heat deposition and other technical concerns associated with the liquid hydrogen targets being developed for cooling intense muon beams. In this study the origin of the outgoing collimated neutron beam is examined. An alternative shielding option for MTA is investigated as well as the hypothetical worst case of experimental setup is considered.

  20. RHIC performance for FY2011 Au+Au heavy ion run

    SciTech Connect (OSTI)

    Marr, G.; Ahrens, L.; Bai, M.; Beebe-Wang, J.; Blackler, I.; Blaskiewicz, M.; Brennan, J.M.; Brown, K.A.; Bruno, D.; Butler, J.; Carlson, C.; Connolly, R.; D'Ottavio, T.; Drees, K.A.; Fedotov, A.V.; Fischer, W.; Fu, W.; Gardner, C.J.; Gassner, D.M.; Glenn, J.W.; Gu, X.; Harvey, M.; Hayes, T.; Hoff, L.; Huang, H.; Ingrassia, P.F.; Jamilkowski, J.P.; Kling, N.; Lafky, M.; Laster, J.S.; Liu, C.; Luo, Y.; Mapes, M.; Marusic, A.; Mernick, K.; Michnoff, R.J.; Minty, M.G.; Montag, C.; Morris, J.; Naylor, C.; Nemesure, S.; Polizzo, S.; Ptitsyn, V.; Robert-Demolaize, G.; Roser, T.; Sampson, P.; Sandberg, J.; Schoefer, V.; Schultheiss, C.; Severino, F.; Shrey, T.; Smith, K.; Steski, D.; Tepikian, S.; Thieberger, P.; Trbojevic, D.; Tsoupas, N.; Tuozzolo, J.E.; VanKuik, B.; Wang, G.; Wilinski, M.; Zaltsman, A.; Zeno, K.; Zhang, S.Y.

    2011-09-04

    Following the Fiscal Year (FY) 2010 (Run-10) Relativistic Heavy Ion Collider (RHIC) Au+Au run, RHIC experiment upgrades sought to improve detector capabilities. In turn, accelerator improvements were made to improve the luminosity available to the experiments for this run (Run-11). These improvements included: a redesign of the stochastic cooling systems for improved reliability; a relocation of 'common' RF cavities to alleviate intensity limits due to beam loading; and an improved usage of feedback systems to control orbit, tune and coupling during energy ramps as well as while colliding at top energy. We present an overview of changes to the Collider and review the performance of the collider with respect to instantaneous and integrated luminosity goals. At the conclusion of the FY 2011 polarized proton run, preparations for heavy ion run proceeded on April 18, with Au+Au collisions continuing through June 28. Our standard operations at 100 GeV/nucleon beam energy was bracketed by two shorter periods of collisions at lower energies (9.8 and 13.5 GeV/nucleon), continuing a previously established program of low and medium energy runs. Table 1 summarizes our history of heavy ion operations at RHIC.

  1. LOPOS; Advanced device isolation for a 0. 8. mu. CMOS/BULK process technology

    SciTech Connect (OSTI)

    Ghezzo, M.; Kaminsky, E.; Nissan-Cohen, Y.; Frank, P.; Saia, R. . Corporate Research and Development Dept.)

    1989-07-01

    Local oxidation of polysilicon over silicon (LOPOS) isolation has been characterized for use in a 0.8 {mu}m CMOS/BULK process with reduced field oxide edge encroachment (bird's beak). Compared to the standard local oxidation of silicon (LOCOS) LOPOS adds a thin polysilicon layer between the stress relief oxide and the overlying nitride without changing the active area patterning procedure. To optimize the LOPOS structure, the thickness of the oxide and nitride layers was varied in a fully-factorial experiment, measuring the bird's beak and checking for the presence of silicon edge defects. It was found that for a 6000{Angstrom} field oxide the bird's beak can be safely reduced to {approx}0.3 {mu}m per side with LOPOS, which is significantly less than {approx}0.55 {mu}m with LOCOS. The corresponding stack consisted of 1500{Angstrom} Si{sub 3}N{sub 4}/550{Angstrom} polysilicon (undoped)/200{Angstrom} SiO{sub 2}. LOPOS fabricated diodes exhibited low leakage of {lt} 0.5 nA/cm{sup 2} and {lt} 0.5 pA/cm for the area and edge components, respectively, while MOS capacitors were breakdown-free up to 8 MV/cm during voltage-stress tests, compared to 6 MV/cm for LOCOS.

  2. Progress on Design and Construction of a MuCool Coupling Solenoid Magnet

    SciTech Connect (OSTI)

    Wang, L.; Liu, Xiao Kun; Xu, FengYu; Li, S.; Pan, Heng; Wu, Hong; Guo, Xinglong; Zheng, ShiXian; Li, Derun; Virostek, Steve; Zisman, Mike; Green, M.A.

    2010-06-28

    The MuCool program undertaken by the US Neutrino Factory and Muon Collider Collaboration is to study the behavior of muon ionization cooling channel components. A single superconducting coupling solenoid magnet is necessary to pursue the research and development work on the performance of high gradient, large size RF cavities immersed in magnetic field, which is one of the main challenges in the practical realization of ionization cooling of muons. The MuCool coupling magnet is to be built using commercial copper based niobium titanium conductors and cooled by two cryo-coolers with each cooling capacity of 1.5 W at 4.2 K. The solenoid magnet will be powered by using a single 300A power supply through a single pair of binary leads that are designed to carry a maximum current of 210A. The magnet is to be passively protected by cold diodes and resistors across sections of the coil and by quench back from the 6061 Al mandrel in order to lower the quench voltage and the hot spot temperature. The magnet is currently under construction. This paper presents the updated design and fabrication progress on the MuCool coupling magnet.

  3. Preparations for p-Au run in 2015

    SciTech Connect (OSTI)

    Liu, C.

    2014-12-31

    The p-Au particle collision is a unique category of collision runs. This is resulted from the different charge mass ratio of the proton and fully stripped Au ion (1 vs.79/197). The p-Au run requires a special acceleration ramp, and movement of a number of beam components as required by the beam trajectories. The DX magnets will be moved for the first time in the history of RHIC. In this note, the planning and preparations for p-Au run will be presented.

  4. Laminin receptor specific therapeutic gold nanoparticles (198AuNP...

    Office of Scientific and Technical Information (OSTI)

    prostate cancer Citation Details In-Document Search Title: Laminin receptor specific therapeutic gold nanoparticles (198AuNP-EGCg) show efficacy in treating prostate cancer ...

  5. Reflow of AuSnSolder Creates Strong Joints [Local Reflow of AuSn Solder: Relating Strength to Microstructure

    SciTech Connect (OSTI)

    Golosker, Ilya V.; Florando, Jeff N.

    2013-02-01

    Local heating of AuSn solder creates reliable bonds. However, small changes in the heat schedule result in significant changes to bond strength and microstructure.

  6. Identification of Au–S complexes on Au(100)

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Walen, Holly; Liu, Da -Jiang; Oh, Junepyo; Yang, Hyun Jin; Kim, Yousoo; Thiel, P. A.

    2016-01-25

    In this study, using a combination of scanning tunneling microscopy and density functional theory (DFT) calculations, we have identified a set of related Au–S complexes that form on Au(100), when sulfur adsorbs and lifts the hexagonal surface reconstruction. The predominant complex is diamond-shaped with stoichiometry Au4S5. All of the complexes can be regarded as combinations of S–Au–S subunits. The complexes exist within, or at the edges of, p(2 × 2) sulfur islands that cover the unreconstructed Au regions, and are observed throughout the range of S coverage examined in this study, 0.009 to 0.12 monolayers. A qualitative model is developedmore » which incorporates competitive formation of complexes, Au rafts, and p(2 × 2) sulfur islands, as Au atoms are released by the surface structure transformation.« less

  7. Sideward flow in Au+Au collisions between 2A and 8A GeV

    SciTech Connect (OSTI)

    Liu, H.; Ajitanand, N.N.; Alexander, J.; Anderson, M.; Best, D.; Brady, F.P.; Case, T.; Caskey, W.; Cebra, D.; Chance, J.; Cole, B.; Crowe, K.; Das, A.; Draper, J.; Gilkes, M.; Gushue, S.; Heffner, M.; Hirsch, A.; Hjort, E.; Huo, L.; Justice, M.; Kaplan, M.; Keane, D.; Kintner, J.; Klay, J.; Krofcheck, D.; Lacey, R.; Lisa, M.A.; Liu, Y.M.; McGrath, R.; Milosevich, Z.; Odyniec, G.; Olson, D.; Panitkin, S.Y.; Porile, N.; Rai, G.; Ritter, H.G.; Romero, J.; Scharenberg, R.; Schroeder, L.S.; Srivastava, B.; Stone, N.T.B.; Symons, T.J.M.; Wang, S.; Whitfield, J.; Wienold, T.; Witt, R.; Wood, L.; Yang, X.; Zhang, W.N.; Zhang, Y.; E895 Collaboration

    2000-04-05

    Using the large acceptance Time Projection Chamber of experiment E895 at Brookhaven, measurements of collective sideward flow in Au + Au collisions at beam energies of 2A, 4A, 6A, and 8A GeV are presented in the form of in-plane transverse momentum

  8. Elliptic flow: transition from out-of-plane to in-plane emissionin Au + Au collisions

    SciTech Connect (OSTI)

    Pinkenburg, C.; Ajitanand, N.N.; Alexander, J.M.; Anderson, M.; Best, D.; Brady, F.P.; Case, T.; Caskey, W.; Cebra, D.; Chance, J.L.; Chung, P.; Cole, B.; Crowe, K.; Das, A.C.; Draper, J.E.; Elmaani, A.; Gilkes, M.L.; Gushue, S.; Heffner, M.; Hirsch, A.S.; Hjort, E.L.; Huo,L.; Justice, M.; Kaplan, M.; Keane, D.; Kintner, J.C.; Klay, J.; Krofcheck, D.; Lacey, R.A.; Lauret, J.; Law, C.; Lisa, M.A.; Liu, H.; Liu, Y.M.; McGrath, R.; Milosevich, Z.; Odyniec, G.; Olson, D.L.; Panitkin, S.Y.; Porile, N.T.; Rai, G.; Ritter, H.G.; Romero, J.L.; Scharenberg, R.P.; Schroeder, L.; Srivastava, B.; Stone, N.T.B.; Symons,T.J.M.; Whitfield, J.; Wienold, T.; Witt, R.; Wood, L.; Zhang, W.N.; E895Collaboration; Danielewicz, P.; Gossiaux, P.B.

    1999-07-31

    We have measured the proton elliptic flow excitation function for the Au+Au system spanning the beam energy range (2-8)A GeV. The excitation function shows a transition from negative to positive elliptic flow at a beam energy, Etr {approx} 4A GeV. Detailed comparisons with calculations from a relativistic Boltzmann equation are presented. The comparisons suggest a softening of the nuclear equation of state from a stiff form (K {approx} 380 MeV) at low beam energies (Ebeam < 2A GeV) to a softer form (K {approx} 210 MeV) at higher energies ( Ebeam < 4A GeV) where the calculated baryon density rho {approx} 4 rho 0.

  9. Target and orbit feedback simulations of a muSR beamline at BNL

    SciTech Connect (OSTI)

    MacKay, W. W.; Fischer, W.; Blaskiewicz, M.; Pile, P.

    2015-05-03

    Well-polarized positive surface muons are a tool to measure the magnetic properties of materials since the precession rate of the spin can be determined from the observation of the positron directions when the muons decay. The use of the AGS complex at BNL has been explored for a muSR facility previously. Here we report simulations of a beamline with a target inside a solenoidal field, and of an orbit feed-back system with single muon beam positioning monitors based on technology available today

  10. CO Oxidation mechanism on CeO2-supported Au nanoclusters

    SciTech Connect (OSTI)

    Kim H. Y.; Henkelman, G.

    2013-09-08

    To reveal the richer chemistry of CO oxidation by CeO2 supported Au Nanoclusters(NCs)/Nanoparticles, we design Au13 and Au12 supported on a flat and a stepped-CeO2 model (Au/CeO2) and study various kinds of CO oxidation mechanisms at the Au-CeO2 interface and the Au NC as well.

  11. Observation of D0 meson nuclear modifications in Au+Au collisions at sNN=200 GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alekseev, I.; Alford, J.; Anson, C. D.; Aparin, A.; Arkhipkin, D.; et al

    2014-09-30

    We report the first measurement of charmed-hadron (D0) production via the hadronic decay channel (D0→K-+π+) in Au+Au collisions at √sNN=200 GeV with the STAR experiment. The charm production cross section per nucleon-nucleon collision at midrapidity scales with the number of binary collisions, Nbin, from p+p to central Au+Au collisions. The D0 meson yields in central Au+Aucollisions are strongly suppressed compared to those in p+p scaled by Nbin, for transverse momenta pT>3 GeV/c, demonstrating significant energy loss of charm quarks in the hot and dense medium. An enhancement at intermediate pT is also observed. Model calculations including strong charm-medium interactions andmore » coalescence hadronization describe our measurements.« less

  12. Observation of D0 meson nuclear modifications in Au+Au collisions at sNN=200 GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alekseev, I.; Alford, J.; Anson, C. D.; Aparin, A.; Arkhipkin, D.; et al

    2014-09-30

    We report the first measurement of charmed-hadron (D0) production via the hadronic decay channel (D0→K-+π+) in Au+Au collisions at √sNN=200 GeV with the STAR experiment. The charm production cross section per nucleon-nucleon collision at midrapidity scales with the number of binary collisions, Nbin, from p+p to central Au+Au collisions. The D0 meson yields in central Au+Aucollisions are strongly suppressed compared to those in p+p scaled by Nbin, for transverse momenta pT>3 GeV/c, demonstrating significant energy loss of charm quarks in the hot and dense medium. An enhancement at intermediate pT is also observed. Model calculations including strong charm-medium interactions andmore »coalescence hadronization describe our measurements.« less

  13. Organometallic oxides: Preparation, structure, and chemical and physical properties of paramagnetic ((. eta. -C sub 5 H sub 5 )NbCl(. mu. -A)) sup 3 (. mu. sub 3 -OH)(. mu. sub 3 -O) (A = Cl, OH) and other oxo-hydroxo clusters of niobium

    SciTech Connect (OSTI)

    Bottomley, F.; Keizer, P.N.; White, P.S. ); Preston, K.F. )

    1990-06-01

    Hydrolysis of Cp{prime}NbCl{sub 4} (Cp{prime} = {eta}{sup 5}-C{sub 5}H{sub 5} (Cp), {eta}-C{sub 5}H{sub 4}Me (Cp{sup 1})) in tetrahydrofuran (THF) gave a mixture of products of general formula (Cp{prime}NbL{sub 4}){sub 2}({mu}-O), where L{sub 4} is a combination of H{sub 2}O and terminal or bridging Cl that gives eight-coordinate, pentavalent, niobium. For Cp{prime} = Cp, a major constituent of the mixture is (CpNb(H{sub 2}O)Cl{sub 3}){sub 2}({mu}-O) {times} 2THF {times} 0.05Et{sub 2}O (1), the structure of which was determined by X-ray diffraction. Reduction of (Cp{prime}NbL{sub 4}){sub 2}({mu}-O) with aluminum powder gave the cluster (Cp{prime}NbCl({mu}-Cl)){sub 3}({mu}{sub 3}-OH)({mu}{sub 3}-O) (2). The structure of 2 (Cp{prime} = Cp) as the THF adduct was determined by X-ray diffraction. Crystal data: monoclinic; P2{sub 1}/c; a = 9.966 (1) {angstrom}, b = 12.471 (2) {angstrom}, c = 20.321 (2) {angstrom}, {beta} = 93.86 (1){degree}.

  14. Zero-point energy, tunneling, and vibrational adiabaticity in the Mu + H2 reaction

    SciTech Connect (OSTI)

    Mielke, Steven L.; Garrett, Bruce C.; Fleming, Donald G.; Truhlar, Donald G.

    2015-01-09

    Abstract: Isotopic substitution of muonium for hydrogen provides an unparalleled opportunity to deepen our understanding of quantum mass effects on chemical reactions. A recent topical review [Aldegunde et al., Mol. Phys. 111, 3169 (2013)] of the thermal and vibrationally-stateselected reaction of Mu with H2 raises a number of issues that are addressed here. We show that some earlier quantum mechanical calculations of the Mu + H2 reaction, which are highlighted in this review and which have been used to benchmark approximate methods, are in error by as much as 19% in the low-temperature limit. We demonstrate that an approximate treatment of the BornOppenheimer diagonal correction that was used in some recent studies is not valid for treating the vibrationally-state-selected reaction. We also discuss why vibrationally adiabatic potentials that neglect bend zero-point energy are not a useful analytical tool for understanding reaction rates and why vibrationally nonadiabatic transitions cannot be understood by considering tunneling through vibrationally adiabatic potentials. Finally, we present calculations on a hierarchical family of potential energy surfaces to assess the sensitivity of rate constants to the quality of the potential surface.

  15. Airbreathing Laser Propulsion Experiments with 1 {mu}m Terawatt Pharos III Laser: Part 1

    SciTech Connect (OSTI)

    Myrabo, L. N.; Lyons, P. W.; Jones, R. A.; Liu, S.; Manka, C.

    2011-11-10

    This basic research study examines the physics of airbreathing laser propulsion at the extreme flux range of 1-2x10{sup 11} W/cm{sup 2}--within the air breakdown threshold for l {mu}m radiation--using the terawatt PHAROS III neodymium-glass pulsed laser. Six different experimental setups were tested using a 34 mm line focus with 66 {mu}m focal waist, positioned near the flat impulse surface. The first campaign investigated impulse generation with the beam oriented almost normal to the target surface, with energies ranging from 23 to 376 J, and pulses of 5 to 30 ns FWHM. Air breakdown/ plasma dynamics were diagnosed with GOI cameras and color photography. Laser generated impulse was quantified with both vertical pendulums and piezoelectric pressure transducers using the standard performance metric, C{sub M}--the momentum coupling coefficient. Part 1 of this 2-part paper covers Campaign no. 1 results including laser plasma diagnostics, pressure gage and vertical pendulum data.

  16. Airbreathing Laser Propulsion Experiments with 1 {mu}m Terawatt Pharos IIILaser: Part 2

    SciTech Connect (OSTI)

    Myrabo, L. N.; Lyons, P. W.; Jones, R. A.; Liu, S.; Manka, C.

    2011-11-10

    This basic research study examines the physics of airbreathing laser propulsion at the extreme flux range of 1-2x10{sup 11} W/cm{sup 2}--within the air breakdown threshold for l {mu}m radiation--using the terawatt Pharos III neodymium-glass pulsed laser. Six different experimental setups were employed using a 34 mm line focus with 66 {mu}m focal waist, positioned near the flat impulse surface. The 2nd Campaign investigated impulse generation with the laser beam focused at grazing incidence across near horizontal target surfaces, with pulse energies ranging from 55 to 186 J, and pulse-widths of 2 to 30 ns FWHM. Laser generated impulse was measured with a horizontal Plexiglas registered ballistic pendulum equipped with either a steel target insert or 0.5 Tesla permanent magnet (NEIT-40), to quantify changes in the momentum coupling coefficient (C{sub M}). Part 2 of this 2-part paper covers Campaign no. 2 results including C{sub M} performance data, and long exposure color photos of LP plasma phenomena.

  17. {mu}-{tau} symmetry, sterile right-handed neutrinos, and leptogenesis

    SciTech Connect (OSTI)

    Riazuddin [National Centre for Physics, Quaid-i-Azam University, Islamabad (Pakistan)

    2008-01-01

    Leptogenesis is studied in a seesaw model with {mu}-{tau} symmetry for SU{sub L}(2)-singlet right-handed neutrinos. It is shown that lepton asymmetry is not zero and is given by the square of the solar neutrino mass difference and can be of the right order of magnitude. Further it involves the same Majorana phase which appears in the neutrinoless double {beta}-decay. In this framework one of the right-handed seesaw partners of light neutrinos can be made massless. This can be identified with a sterile neutrino, once it acquires a tiny mass ({approx_equal}1 eV) when {mu}-{tau} symmetry is broken in the right-handed neutrino sector. The above mentioned sterile neutrino together with another one can be identified to explain the MiniBooNE and LSND results. The light 5x5 neutrino mass matrix is completely fixed if CP is conserved and so is the effective mass for neutrinoless double {beta}-decay.

  18. Corrigendum to “Suppression of Υ production in d+Au and Au+Au collisions at √ SNN = 200 GeV" [Phys. Lett. B 735 (2014) 127-137

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adamczyk, L.

    2015-04-01

    We report measurements of Υ meson production in p + p, d + Au, and Au+Au collisions using the STAR detector at RHIC. We compare the Υ yield to the measured cross section in p + p collisions in order to quantify any modifications of the yield in cold nuclear matter using d + Au data and in hot nuclear matter using Au+Au data separated into three centrality classes. Our p + p measurement is based on three times the statistics of our previous result. We obtain a nuclear modification factor for Upsilon (1S + 2S + 3S) in themore » rapidity range |y| < 1 in d + Au collisions of RdAu = 0.79 ± 0.24(stat.) ± 0.03(syst.) ± 0.10(p + p syst.). A comparison with models including shadowing and initial state parton energy loss indicates the presence of additional cold-nuclear matter suppression. Similarly, in the top 10% most-central Au + Au collisions, we measure a nuclear modification factor of R AA = 0.49 ±0.1(stat.) ±0.02(syst.) ±0.06(p + p syst.), which is a larger suppression factor than that seen in cold nuclear matter. Our results are consistent with complete suppression of excited-state Upsilon mesons in Au + Au collisions. The additional suppression in Au + Au is consistent with the level expected in model calculations that include the presence of a hot, deconfined Quark–Gluon Plasma. However, understanding the suppression seen in d + Au is still needed before any definitive statements about the nature of the suppression in Au + Au can be made.« less

  19. Corrigendum to Suppression of ? production in d+Au and Au+Au collisions at ? SNN = 200 GeV" [Phys. Lett. B 735 (2014) 127-137

    SciTech Connect (OSTI)

    Adamczyk, L.

    2015-04-01

    We report measurements of ? meson production in p + p, d + Au, and Au+Au collisions using the STAR detector at RHIC. We compare the ? yield to the measured cross section in p + p collisions in order to quantify any modifications of the yield in cold nuclear matter using d + Au data and in hot nuclear matter using Au+Au data separated into three centrality classes. Our p + p measurement is based on three times the statistics of our previous result. We obtain a nuclear modification factor for Upsilon (1S + 2S + 3S) in the rapidity range |y| < 1 in d + Au collisions of RdAu = 0.79 0.24(stat.) 0.03(syst.) 0.10(p + p syst.). A comparison with models including shadowing and initial state parton energy loss indicates the presence of additional cold-nuclear matter suppression. Similarly, in the top 10% most-central Au + Au collisions, we measure a nuclear modification factor of R AA = 0.49 0.1(stat.) 0.02(syst.) 0.06(p + p syst.), which is a larger suppression factor than that seen in cold nuclear matter. Our results are consistent with complete suppression of excited-state Upsilon mesons in Au + Au collisions. The additional suppression in Au + Au is consistent with the level expected in model calculations that include the presence of a hot, deconfined QuarkGluon Plasma. However, understanding the suppression seen in d + Au is still needed before any definitive statements about the nature of the suppression in Au + Au can be made.

  20. Graphene-Au Nanoparticles Composite-Based Electrochemical Aptamer

    Office of Scientific and Technical Information (OSTI)

    Biosensors (Conference) | SciTech Connect Graphene-Au Nanoparticles Composite-Based Electrochemical Aptamer Biosensors Citation Details In-Document Search Title: Graphene-Au Nanoparticles Composite-Based Electrochemical Aptamer Biosensors × You are accessing a document from the Department of Energy's (DOE) SciTech Connect. This site is a product of DOE's Office of Scientific and Technical Information (OSTI) and is provided as a public service. Visit OSTI to utilize additional information

  1. Exploiting Intrinsic Triangular Geometry in Relativistic He 3 + Au

    Office of Scientific and Technical Information (OSTI)

    Collisions to Disentangle Medium Properties (Journal Article) | SciTech Connect Exploiting Intrinsic Triangular Geometry in Relativistic He 3 + Au Collisions to Disentangle Medium Properties Citation Details In-Document Search Title: Exploiting Intrinsic Triangular Geometry in Relativistic He 3 + Au Collisions to Disentangle Medium Properties Authors: Nagle, J. L. ; Adare, A. ; Beckman, S. ; Koblesky, T. ; Koop, J. Orjuela ; McGlinchey, D. ; Romatschke, P. ; Carlson, J. ; Lynn, J. E. ;

  2. Graphene-Au Nanoparticles Composite-Based Electrochemical Aptamer

    Office of Scientific and Technical Information (OSTI)

    Biosensors (Conference) | SciTech Connect Graphene-Au Nanoparticles Composite-Based Electrochemical Aptamer Biosensors Citation Details In-Document Search Title: Graphene-Au Nanoparticles Composite-Based Electrochemical Aptamer Biosensors Authors: Guo, Shaojun [1] + Show Author Affiliations Los Alamos National Laboratory [Los Alamos National Laboratory Publication Date: 2014-03-27 OSTI Identifier: 1126641 Report Number(s): LA-UR-13-28234 DOE Contract Number: AC52-06NA25396 Resource Type:

  3. Corrigendum to “Suppression of Υ production in d+Au and Au+Au collisions at √ SNN = 200 GeV" [Phys. Lett. B 735 (2014) 127-137

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adamczyk, L.

    2015-04-01

    We report measurements of Υ meson production in p + p, d + Au, and Au+Au collisions using the STAR detector at RHIC. We compare the Υ yield to the measured cross section in p + p collisions in order to quantify any modifications of the yield in cold nuclear matter using d + Au data and in hot nuclear matter using Au+Au data separated into three centrality classes. Our p + p measurement is based on three times the statistics of our previous result. We obtain a nuclear modification factor for Upsilon (1S + 2S + 3S) in themore »rapidity range |y| dAu = 0.79 ± 0.24(stat.) ± 0.03(syst.) ± 0.10(p + p syst.). A comparison with models including shadowing and initial state parton energy loss indicates the presence of additional cold-nuclear matter suppression. Similarly, in the top 10% most-central Au + Au collisions, we measure a nuclear modification factor of R AA = 0.49 ±0.1(stat.) ±0.02(syst.) ±0.06(p + p syst.), which is a larger suppression factor than that seen in cold nuclear matter. Our results are consistent with complete suppression of excited-state Upsilon mesons in Au + Au collisions. The additional suppression in Au + Au is consistent with the level expected in model calculations that include the presence of a hot, deconfined Quark–Gluon Plasma. However, understanding the suppression seen in d + Au is still needed before any definitive statements about the nature of the suppression in Au + Au can be made.« less

  4. SEARCHING FOR THE HIGHEST REDSHIFT SOURCES IN 250-500 {mu}m SUBMILLIMETER SURVEYS

    SciTech Connect (OSTI)

    Pope, Alexandra; Chary, Ranga-Ram

    2010-06-01

    We explore a technique for identifying the highest redshift (z>4) sources in Herschel/SPIRE and BLAST submillimeter surveys by localizing the position of the far-infrared dust peak. Just as Spitzer/IRAC was used to identify stellar 'bump' sources, the far-IR peak is also a redshift indicator; although the latter also depends on the average dust temperature. We demonstrate the wide range of allowable redshifts for a reasonable range of dust temperatures and show that it is impossible to constraint the redshift of individual objects using solely the position of the far-IR peak. By fitting spectral energy distribution models to simulated Herschel/SPIRE photometry we show the utility of radio and/or far-infrared data in breaking this degeneracy. With prior knowledge of the dust temperature distribution it is possible to obtain statistical samples of high redshift submillimeter galaxy (SMG) candidates. We apply this technique to the BLAST survey of ECDFS to constrain the number of dusty galaxies at z>4. We find 8 {+-} 2 galaxies with flux density ratios of S {sub 500}>S {sub 350}; this sets an upper limit of 17 {+-} 4 deg{sup -2} if we assume all are at z>4. This is <35 % of all 500 {mu}m-selected galaxies down to S {sub 500}>45 mJy (L {sub IR}>2 x 10{sup 13} L {sub sun} for z>4). Modeling with conventional temperature and redshift distributions estimates the percentage of these 500 {mu}m peak galaxies at z>4 to be between 10% and 85%. Our results are consistent with other estimates of the number density of very high redshift SMGs and follow the decline in the star formation rate density at z>4.

  5. Composition, process, and apparatus, for removal of water and silicon mu-oxides from chlorosilanes

    DOE Patents [OSTI]

    Tom, Glenn M.; McManus, James V.

    1991-10-15

    A scavenger composition having utility for removal of water and silicon mu-oxide impurities from chlorosilanes, such scavenger composition comprising: (a) a support; and (b) associated with the support, one or more compound(s) selected from the group consisting of compounds of the formula: R.sub.a-x MCl.sub.x wherein: M is a metal selected from the group consisting of the monovalent metals lithium, sodium, and potassium; the divalent metals magnesium, strontium, barium, and calcium; and the trivalent metal aluminum; R is alkyl; a is a number equal to the valency of metal M; and x is a number having a value from 0 to a, inclusive; and wherein said compound(s) of the formula R.sub.a-x MCl.sub.x have been activated for impurity-removal service by a reaction scheme selected from those of the group consisting of: (i) reaction of such compound(s) with hydrogen chloride to form a first reaction product therefrom, followed by reaction of the first reaction product with a chlorosilane of the formula: SiH.sub.4"y Cl.sub.y, wherein y is a number having a value of from 1 to 3, inclusive; and (ii) reaction of such compound(s) with a chlorosilane of the formula: SiH.sub.4-y Cl.sub.y wherein y is a number having a value of 1 to 3, inclusive. A corresponding method of making the scavenger composition, and of purifying a chlorosilane which contains oxygen and silicon mu-oxide impurities, likewise are disclosed, together with a purifier apparatus, in which a bed of the scavenger composition is disposed. The composition, purification process, and purifier apparatus of the invention have utility in purifying gaseous chlorosilanes which are employed in the semiconductor industry as silicon source reagents for forming epitaxial silicon layers.

  6. Process for removal of water and silicon mu-oxides from chlorosilanes

    DOE Patents [OSTI]

    Tom, Glenn M.; McManus, James V.

    1992-03-10

    A scavenger composition having utility for removal of water and silicon mu-oxide impurities from chlorosilanes, such scavenger composition comprising: (a) a support; and (b) associated with the support, one or more compound(s) selected from the group consisting of compounds of the formula: R.sub.a-x MCl.sub.x wherein: M is a metal selected from the group consisting of the monovalent metals lithium, sodium, and potassium; the divalent metals magnesium, strontium, barium, and calcium; and the trivalent metal aluminum; R is alkyl; a is a number equal to the valency of metal M; and x is a number having a value of from 0 to a, inclusive; and wherein said compound(s) of the formula R.sub.a-x MCl.sub.x have been activated for impurity-removal service by a reaction scheme selected from those of the group consisting of: (i) reaction of such compound(s) with hydrogen chloride to form a first reaction product therefrom, followed by reaction of the first reaction product with a chlorosilane of the formula: SiH.sub.4-y Cl.sub.y, wherein y is a number having a value of from 1 to 3, inclusive; and (ii) reaction of such compound(s) with a chlorosilane of the formula: SiH.sub.4-y Cl.sub.y wherein y is a number having a value of 1 to 3, inclusive. A corresponding method of making the scavenger composition, and of purifying a chlorosilane which contains oxygen and silicon mu-oxide impurities, likewise are disclosed, together with a purifier apparatus, in which a bed of the scavenger composition is disposed. The composition, purification process, and purifier apparatus of the invention have utility in purifying gaseous chlorosilanes which are employed in the semiconductor industry as silicon source reagents for forming epitaxial silicon layers.

  7. METHANOL MASER EMISSION FROM GALACTIC CENTER SOURCES WITH EXCESS 4.5 {mu}m EMISSION

    SciTech Connect (OSTI)

    Chambers, E. T.; Yusef-Zadeh, F.; Roberts, D. E-mail: zadeh@northwestern.edu

    2011-05-20

    We present a study of signatures of on-going star formation in a sample of protostellar objects with enhanced 4.5 {mu}m emission ('green' sources) near the Galactic center. To understand how star formation in the Galactic center region compares to that of the Galactic disk, we used the Expanded Very Large Array to observe radiatively excited Class II 6.7 GHz CH{sub 3}OH masers and collisionally excited Class I 44 GHz CH{sub 3}OH masers, both tracers of high-mass star formation, toward a sample of 34 Galactic center and foreground 'green' sources. We find that 33% {+-} 15% of Galactic center sources are coincident with 6.7 GHz masers, and that 44% {+-} 17% of foreground sources are coincident with 6.7 GHz masers. For 44 GHz masers, we find correlation rates of 27% {+-} 13% and 25% {+-} 13% for Galactic center green sources and foreground green sources, respectively. Based on these CH{sub 3}OH maser detection rates, as well as correlations of green sources with other tracers of star formation, such as 24 {mu}m emission and infrared dark clouds (IRDCs), we find no significant difference between the green sources in the Galactic center and those foreground to it. This suggests that once the star formation process has begun, the environmental differences between the Galactic center region and the Galactic disk have little effect on its observational signatures. We do find, however, some evidence that may support a recent episode of star formation in the Galactic center region.

  8. Asymmetrical-fan tranmission CT on SPECT to derive {mu}-maps for attenuation correction

    SciTech Connect (OSTI)

    Loncaric, S.; Huang, G.; Ni, B. [Rush-Presbyterian-St. Luke`s Medical Center, Chicago, IL (United States)] [and others

    1994-05-01

    For proper attenuation correction of SPECT images, an appropriate {mu}-map properly registered with each imaging slices is needed. Among the many techniques for {mu}-map derivation, simultaneous or sequential fan-beam transmission CT (TCT), on the same SPECT system with the same acquisition settings, have advantages of being practical while ensuring registration. However, the problems are: (1) limited FOV for thoracic imaging, projection would be truncated with a typical size detector, (2) lack of room for placing the transmission source in many SPECT systems. We have developed a new sampling scheme to solve the problems mentioned above. This scheme uses an asymmetrical-fan geometry (AFG), which samples only half of the field, the other half would be sampled after an 180{degrees} detector rotation. This technique completes the minimum sampling requirement in a 360{degrees} detector rotation and yields a relatively large FOV defined by the outside edge of the sampling fan. We have confirmed the feasibility of the AFG sampling on a 3-head SPECT system to provide a large FOV for TCT of most patient. The TCT sampling scheme is achieved with an asymmetrical-fan collimator. We have developed the required new reconstruction algorithms and derived excellent reconstructed images of phantoms and human subjects. We propose to have this technique implemented in a short and fast transmission scan in a multi-head SPECT system, after emission imaging, because the detectors have to be pulled out to make room for the transmission source. The imaging field can even exceed the full field size of the detector. MS would be possible when an obtuse sampling fan is formed by shifting the source outward further, provided the central FOV is properly covered with a supplementary sampling scheme, e.g., using another TCT with a fan-beam collimator on another one of the detectors.

  9. Azimuthal anisotophy in U + U and Au + Au collisions at RHIC

    SciTech Connect (OSTI)

    Adamczyk, L.

    2015-11-24

    Collisions between prolate uranium nuclei are used to study how particle production and azimuthal anisotropies depend on initial geometry in heavy-ion collisions. We report the two- and four-particle cumulants, v2{2} and v2{4}, for charged hadrons from U+U collisions at √SNN = 193 GeV and Au+Au collisions at √SNN = 200 GeV. Nearly fully overlapping collisions are selected based on the energy deposited by spectators in zero degree calorimeters (ZDCs). Within this sample, the observed dependence of v2{2} on multiplicity demonstrates that ZDC information combined with multiplicity can preferentially select different overlap configurations in U+U collisions. As a result, we also show that v2 vs multiplicity can be better described by models, such as gluon saturation or quark participant models, that eliminate the dependence of the multiplicity on the number of binary nucleon-nucleon collisions.

  10. Azimuthal anisotophy in U + U and Au + Au collisions at RHIC

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adamczyk, L.

    2015-11-24

    Collisions between prolate uranium nuclei are used to study how particle production and azimuthal anisotropies depend on initial geometry in heavy-ion collisions. We report the two- and four-particle cumulants, v2{2} and v2{4}, for charged hadrons from U+U collisions at √SNN = 193 GeV and Au+Au collisions at √SNN = 200 GeV. Nearly fully overlapping collisions are selected based on the energy deposited by spectators in zero degree calorimeters (ZDCs). Within this sample, the observed dependence of v2{2} on multiplicity demonstrates that ZDC information combined with multiplicity can preferentially select different overlap configurations in U+U collisions. As a result, we alsomore » show that v2 vs multiplicity can be better described by models, such as gluon saturation or quark participant models, that eliminate the dependence of the multiplicity on the number of binary nucleon-nucleon collisions.« less

  11. RHIC PERFORMANCE DURING THE FY10 200 GeV Au+Au HEAVY ION RUN

    SciTech Connect (OSTI)

    Brown, K.A.; Ahrens, L.; Bai, M.; Beebe-Wang, J.; Blaskiewicz, M.; Brennan, J.; Bruno, D.; Carlson, C.; Connolly, R.; de Maria, R.; DOttavio, T.; Drees, A.; Fischer, W.; Fu, W.; Gardner, C.; Gassner, D.; Glenn, J.W.; Hao, Y.; Harvey, M.; Hayes, T.; Hoff, L.; Huang, H.; Laster, J.; Lee, R.; Litvinenko, V.; Luo, Y.; MacKay, W.; Marr, G.; Marusic, A.; Mernick, K.; Michnoff, R.; Minty, M.; Montag, C.; Morris, J.; Nemesure, S.; Oerter, B.; Pilat, F.; Ptitsyn, V.; Robert-Demolaize, G.; Roser, T.; Russo, T.; Sampson, P.; Sandberg, J.; Satogata, T.; Severino, F.; Schoefer, V.; Schultheiss, C.; Smith, K.; Steski, D.; Tepikian, S.; Theisen, C.; Thieberger, P.; Trbojevic, D.; Tsoupas, N.; Tuozzolo, J.; Wang, G.; Wilinski, M.; Zaltsman, A.; Zeno, K.; Zhang, S.Y.

    2010-05-23

    Since the last successful RHIC Au+Au run in 2007 (Run-7), the RHIC experiments have made numerous detector improvements and upgrades. In order to benefit from the enhanced detector capabilities and to increase the yield of rare events in the acquired heavy ion data a significant increase in luminosity is essential. In Run-7 RHIC achieved an average store luminosity of = 12 x 10{sup 26} cm{sup -2} s{sup -1} by operating with 103 bunches (out of 111 possible), and by squeezing to {beta}* = 0.85 m. This year, Run-10, we achieved = 20 x 10{sup 26} cm{sup -2} s{sup -1}, which put us an order of magnitude above the RHIC design luminosity. To reach these luminosity levels we decreased {beta}* to 0.75 m, operated with 111 bunches per ring, and reduced longitudinal and transverse emittances by means of bunched-beam stochastic cooling. In addition we introduced a lattice to suppress intra-beam scattering (IBS) in both RHIC rings, upgraded the RF control system, and separated transition crossing times in the two rings. We present an overview of the changes and the results of Run-10 performance.

  12. Apparatus and method for generating continuous wave 16. mu. m laser radiation using gaseous CF/sub 4/

    DOE Patents [OSTI]

    Telle, J.M.

    1984-05-01

    Apparatus and method for generating continuous wave 16 ..mu..m laser radiation using gaseous CF/sub 4/. Laser radiation at 16 ..mu..m has been observed in a cooled static cell containing low pressure CF/sub 4/ optically pumped by an approximately 3 W output power c-w CO/sub 2/ laser. The laser cavity employed was a multiple-pass off-axis-path two spherical mirror ring resonator. Unidirectional CF/sub 4/ laser output power at 615 cm/sup -1/ exceeded 2 mW. Computer calculations indicate that for modest pump powers of about 40 W, approximately 1 W of emitted laser radiation at 16 ..mu..m might be obtained.

  13. Apparatus and method for generating continuous wave 16 .mu.m laser radiation using gaseous CF.sub.4

    DOE Patents [OSTI]

    Telle, John M.

    1986-01-01

    Apparatus and method for generating continuous wave 16 .mu.m laser radiation using gaseous CF.sub.4. Laser radiation at 16 .mu.m has been observed in a cooled static cell containing low pressure CF.sub.4 optically pumped by an approximately 3 W output power cw CO.sub.2 laser. The laser cavity employed was a multiple-pass off-axis-path two spherical mirror ring resonator. Unidirectional CF.sub.4 laser output power at 615 cm.sup.-1 exceeded 2 mW. Computer calculations indicate that for modest pump powers of about 40 W, approximately 1 W of emitted laser radiation at 16 .mu.m might be obtained.

  14. Search for the Decays B0(s) ---> e+ mu- and B0(s) ---> e+ e- in CDF Run. II.

    SciTech Connect (OSTI)

    Aaltonen, T.; /Helsinki Inst. of Phys.; Adelman, J.; /Chicago U., EFI; Akimoto, T.; /Tsukuba U.; Alvarez Gonzalez, B.; /CSIC, Catalunya; Amerio, S.; /INFN, Padua; Amidei, D.; /Michigan U.; Anastassov, A.; /Northwestern U.; Annovi, A.; /Frascati; Antos, J.; /Comenius U.; Apollinari, G.; /Fermilab; Apresyan, A.; /Purdue U. /Waseda U.

    2009-01-01

    The authors report results from a search for the lepton flavor violating decays B{sub (s)}{sup 0} {yields} e{sup +}{mu}{sup -}, and the flavor-changing neutral-current decays B{sub (s)}{sup 0} {yields} e{sup +}e{sup -}. The analysis uses data corresponding to 2 fb{sup -1} of integrated luminosity of p{bar p} collisions at {radical}s = 1.96 TeV collected with the upgraded Collider Detector (CDF II) at the Fermilab Tevatron. The observed number of B{sub (s)}{sup 0} candidates is consistent with background expectations. The resulting bayesian upper limits on the branching ratios at 90% credibility level are {Beta}(B{sub s}{sup 0} {yields} e{sup +}{mu}{sup -}) < 2.0 x 10{sup -7}, {Beta}(B{sup 0} {yields} e{sup +}{mu}{sup -}) < 6.4 x 10{sup -8}, {Beta}(B{sub s}{sup 0} {yields} e{sup +}e{sup -}) < 2.8 x 10{sup -7} and {Beta}(B{sup 0} {yields} e{sup +}e{sup -}) < 8.3 x 10{sup -8}. From the limits on {Beta}(B{sub (s)}{sup 0} {yields} e{sup +}{mu}{sup -}), the following lower bounds on the Pati-Salam leptoquark masses are also derived: M{sub LQ}(B{sub s}{sup 0} {yields} e{sup +}{mu}{sup -}) > 47.8 TeV/c{sup 2}, and M{sub LQ}(B{sup 0} {yields} e{sup +}{mu}{sup -}) > 59.3 TeV/c{sup 2}, at 90% credibility level.

  15. Measurement of J/? Azimuthal Anisotropy in Au+Au Collisions at ?sNN=200 GeV

    SciTech Connect (OSTI)

    Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alekseev, I.; Alford, J.; Anson, C. D.; Aparin, A.; Arkhipkin, D.; Aschenauer, E.; Averichev, G. S.; Balewski, J.; Banerjee, A.; Barnovska, Z.; Beavis, D. R.; Bellwied, R.; Betancourt, M. J.; Betts, R. R.; Bhasin, A.; Bhati, A. K.; Bhattarai, P.; Bichsel, H.; Bielcik, J.; Bielcikova, J.; Bland, L. C.; Bordyuzhin, I. G.; Borowski, W.; Bouchet, J.; Brandin, A. V.; Brovko, S. G.; Bruna, E.; Bltmann, S.; Bunzarov, I.; Burton, T. P.; Butterworth, J.; Cai, X. Z.; Caines, H.; Caldern de la Barca Snchez, M.; Cebra, D.; Cendejas, R.; Cervantes, M. C.; Chaloupka, P.; Chang, Z.; Chattopadhyay, S.; Chen, H. F.; Chen, J. H.; Chen, J. Y.; Chen, L.; Cheng, J.; Cherney, M.; Chikanian, A.; Christie, W.; Chung, P.; Chwastowski, J.; Codrington, M. J. M.; Corliss, R.; Cramer, J. G.; Crawford, H. J.; Cui, X.; Das, S.; Davila Leyva, A.; De Silva, L. C.; Debbe, R. R.; Dedovich, T. G.; Deng, J.; Derradi de Souza, R.; Dhamija, S.; di Ruzza, B.; Didenko, L.; Ding, F.; Dion, A.; Djawotho, P.; Dong, X.; Drachenberg, J. L.; Draper, J. E.; Du, C. M.; Dunkelberger, L. E.; Dunlop, J. C.; Efimov, L. G.; Elnimr, M.; Engelage, J.; Eppley, G.; Eun, L.; Evdokimov, O.; Fatemi, R.; Fazio, S.; Fedorisin, J.; Fersch, R. G.; Filip, P.; Finch, E.; Fisyak, Y.; Flores, E.; Gagliardi, C. A.; Gangadharan, D. R.; Garand, D.; Geurts, F.; Gibson, A.; Gliske, S.; Grebenyuk, O. G.; Grosnick, D.; Gupta, A.; Gupta, S.; Guryn, W.; Haag, B.; Hajkova, O.; Hamed, A.; Han, L-X.; Harris, J. W.; Hays-Wehle, J. P.; Heppelmann, S.; Hirsch, A.; Hoffmann, G. W.; Hofman, D. J.; Horvat, S.; Huang, B.; Huang, H. Z.; Huck, P.; Humanic, T. J.; Igo, G.; Jacobs, W. W.; Jena, C.; Judd, E. G.; Kabana, S.; Kang, K.; Kapitan, J.; Kauder, K.; Ke, H. W.; Keane, D.; Kechechyan, A.; Kesich, A.; Kikola, D. P.; Kiryluk, J.; Kisel, I.; Kisiel, A.; Klein, S. R.; Koetke, D. D.; Kollegger, T.; Konzer, J.; Koralt, I.; Korsch, W.; Kotchenda, L.; Kravtsov, P.; Krueger, K.; Kulakov, I.; Kumar, L.; Lamont, M. A. C.; Landgraf, J. M.; Landry, K. D.; LaPointe, S.; Lauret, J.; Lebedev, A.; Lednicky, R.; Lee, J. H.; Leight, W.; LeVine, M. J.; Li, C.; Li, W.; Li, X.; Li, X.; Li, Y.; Li, Z. M.; Lima, L. M.; Lisa, M. A.; Liu, F.; Ljubicic, T.; Llope, W. J.; Longacre, R. S.; Lu, Y.; Luo, X.; Luszczak, A.; Ma, G. L.; Ma, Y. G.; Madagodagettige Don, D. M. M. D.; Mahapatra, D. P.; Majka, R.; Margetis, S.; Markert, C.; Masui, H.; Matis, H. S.; McDonald, D.; McShane, T. S.; Mioduszewski, S.; Mitrovski, M. K.; Mohammed, Y.; Mohanty, B.; Mondal, M. M.; Munhoz, M. G.; Mustafa, M. K.; Naglis, M.; Nandi, B. K.; Nasim, Md.; Nayak, T. K.; Nelson, J. M.; Nogach, L. V.; Novak, J.; Odyniec, G.; Ogawa, A.; Oh, K.; Ohlson, A.; Okorokov, V.; Oldag, E. W.; Oliveira, R. A. N.; Olson, D.; Pachr, M.; Page, B. S.; Pal, S. K.; Pan, Y. X.; Pandit, Y.; Panebratsev, Y.; Pawlak, T.; Pawlik, B.; Pei, H.; Perkins, C.; Peryt, W.; Pile, P.; Planinic, M.; Pluta, J.; Poljak, N.; Porter, J.; Poskanzer, A. M.; Powell, C. B.; Pruneau, C.; Pruthi, N. K.; Przybycien, M.; Pujahari, P. R.; Putschke, J.; Qiu, H.; Ramachandran, S.; Raniwala, R.; Raniwala, S.; Ray, R. L.; Riley, C. K.; Ritter, H. G.; Roberts, J. B.; Rogachevskiy, O. V.; Romero, J. L.; Ross, J. F.; Ruan, L.; Rusnak, J.; Sahoo, N. R.; Sahu, P. K.; Sakrejda, I.; Salur, S.; Sandacz, A.; Sandweiss, J.; Sangaline, E.; Sarkar, A.; Schambach, J.; Scharenberg, R. P.; Schmah, A. M.; Schmidke, B.; Schmitz, N.; Schuster, T. R.; Seger, J.; Seyboth, P.; Shah, N.; Shahaliev, E.; Shao, M.; Sharma, B.; Sharma, M.; Shi, S. S.; Shou, Q. Y.; Sichtermann, E. P.; Singaraju, R. N.; Skoby, M. J.; Smirnov, D.; Smirnov, N.; Solanki, D.; Sorensen, P.; deSouza, U. G.; Spinka, H. M.; Srivastava, B.; Stanislaus, T. D. S.; Stevens, J. R.; Stock, R.; Strikhanov, M.; Stringfellow, B.; Suaide, A. A. P.; Suarez, M. C.; Sumbera, M.; Sun, X. M.; Sun, Y.; Sun, Z.; Surrow, B.; Svirida, D. N.; Symons, T. J. M.; Szanto de Toledo, A.; Takahashi, J.; Tang, A. H.; Tang, Z.; Tarini, L. H.; Tarnowsky, T.; Thomas, J. H.; Tian, J.; Timmins, A. R.; Tlusty, D.; Tokarev, M.; Trentalange, S.; Tribble, R. E.; Tribedy, P.; Trzeciak, B. A.; Tsai, O. D.; Turnau, J.; Ullrich, T.; Underwood, D. G.; Van Buren, G.; van Nieuwenhuizen, G.; Vanfossen, J. A.; Varma, R.; Vasconcelos, G. M. S.; Videbk, F.; Viyogi, Y. P.; Vokal, S.; Voloshin, S. A.; Vossen, A.; Wada, M.; Wang, F.; Wang, G.; Wang, H.; Wang, J. S.; Wang, Q.; Wang, X. L.; Wang, Y.; Webb, G.; Webb, J. C.; Westfall, G. D.; Whitten, C.; Wieman, H.; Wissink, S. W.; Witt, R.; Wu, Y. F.; Xiao, Z.; Xie, W.; Xin, K.; Xu, H.; Xu, N.; Xu, Q. H.; Xu, W.; Xu, Y.; Xu, Z.; Xue, L.; Yang, Y.; Yang, Y.; Yepes, P.; Yi, L.; Yip, K.; Yoo, I-K.; Zawisza, M.; Zbroszczyk, H.; Zhang, J. B.; Zhang, S.; Zhang, X. P.; Zhang, Y.

    2013-08-02

    The measurement of J/? azimuthal anisotropy is presented as a function of transverse momentum for different centralities in Au+Au collisions at ?sNN>/sub>=200 GeV. The measured J/? elliptic flow is consistent with zero within errors for transverse momentum between 2 and 10 GeV/c. Our measurement suggests that J/? particles with relatively large transverse momenta are not dominantly produced by coalescence from thermalized charm quarks, when comparing to model calculations.

  16. Measurement of J/? Azimuthal Anisotropy in Au+Au Collisions at ?sNN=200 GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alekseev, I.; Alford, J.; Anson, C. D.; Aparin, A.; Arkhipkin, D.; et al

    2013-08-02

    The measurement of J/? azimuthal anisotropy is presented as a function of transverse momentum for different centralities in Au+Au collisions at ?sNN>/sub>=200 GeV. The measured J/? elliptic flow is consistent with zero within errors for transverse momentum between 2 and 10 GeV/c. Our measurement suggests that J/? particles with relatively large transverse momenta are not dominantly produced by coalescence from thermalized charm quarks, when comparing to model calculations.

  17. 150 {mu}A 18F{sup -} target and beam port upgrade for the IBA 18/9 cyclotron

    SciTech Connect (OSTI)

    Stokely, M. H.; Peeples, J. L.; Poorman, M. C.; Magerl, M.; Siemer, T.; Brisard, P.; Wieland, B. W.

    2012-12-19

    A high power ({approx}3 kW) target platform has been developed for the IBA 18/9 cyclotron. New designs for the airlock, collimator and target subsystems have been fabricated and deployed. The primary project goal is reliable commercial production of 18F{sup -} at 150 {mu}A or greater, while secondary goals include improving serviceability and extending service intervals relative to OEM systems. Reliable operation in a production environment has been observed at beam currents up to 140 {mu}A. Challenges include ion source lifetime and localized peaking in the beam intensity distribution.

  18. Heterojunction metal-oxide-metal Au-Fe{sub 3}O{sub 4}-Au single nanowire device for spintronics

    SciTech Connect (OSTI)

    Reddy, K. M. Punnoose, Alex; Hanna, Charles; Padture, Nitin P.

    2015-05-07

    In this report, we present the synthesis of heterojunction magnetite nanowires in alumina template and describe magnetic and electrical properties from a single nanowire device for spintronics applications. Heterojunction Au-Fe-Au nanowire arrays were electrodeposited in porous aluminum oxide templates, and an extensive and controlled heat treatment process converted Fe segment to nanocrystalline cubic magnetite phase with well-defined Au-Fe{sub 3}O{sub 4} interfaces as confirmed by the transmission electron microscopy. Magnetic measurements revealed Verwey transition shoulder around 120 K and a room temperature coercive field of 90 Oe. Current–voltage (I-V) characteristics of a single Au-Fe{sub 3}O{sub 4}-Au nanowire have exhibited Ohmic behavior. Anomalous positive magnetoresistance of about 0.5% is observed on a single nanowire, which is attributed to the high spin polarization in nanowire device with pure Fe{sub 3}O{sub 4} phase and nanocontact barrier. This work demonstrates the ability to preserve the pristine Fe{sub 3}O{sub 4} and well defined electrode contact metal (Au)–magnetite interface, which helps in attaining high spin polarized current.

  19. Rationalization of Au concentration and distribution in AuNi@Pt core-shell nanoparticles for oxygen reduction reaction

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    An, Wei; Liu, Ping

    2015-09-18

    Improving the activity and stability of Pt-based core–shell nanocatalysts for proton exchange membrane fuel cells while lowering Pt loading has been one of the big challenges in electrocatalysis. Here, using density functional theory, we report the effect of adding Au as the third element to enhance the durability and activity of Ni@Pt core–shell nanoparticles (NPs) during the oxygen reduction reaction (ORR). Our results show that the durability and activity of a Ni@Pt NP can be finely tuned by controlling Au concentration and distribution. For a NiAu@Pt NP, the durability can be greatly promoted by thermodynamically favorable segregation of Au tomore » replace the Pt atoms at vertex, edge, and (100) facets on the shell, while still keeping the ORR activity on the active Pt(111) shell as high as that of Ni@Pt nanoparticles. Such behavior strongly depends on a direct interaction with the Ni interlayer. The results not only highlight the importance of interplay between surface strain on the shell and the interlayer–shell interaction in determining the durability and activity but also provide guidance on how to maximize the usage of Au to optimize the performance of core–shell (Pt) nanoparticles. As a result, such understanding has allowed us to discover a novel NiAu@Pt nanocatalyst for the ORR.« less

  20. Rationalization of Au concentration and distribution in AuNi@Pt core-shell nanoparticles for oxygen reduction reaction

    SciTech Connect (OSTI)

    An, Wei; Liu, Ping

    2015-09-18

    Improving the activity and stability of Pt-based coreshell nanocatalysts for proton exchange membrane fuel cells while lowering Pt loading has been one of the big challenges in electrocatalysis. Here, using density functional theory, we report the effect of adding Au as the third element to enhance the durability and activity of Ni@Pt coreshell nanoparticles (NPs) during the oxygen reduction reaction (ORR). Our results show that the durability and activity of a Ni@Pt NP can be finely tuned by controlling Au concentration and distribution. For a NiAu@Pt NP, the durability can be greatly promoted by thermodynamically favorable segregation of Au to replace the Pt atoms at vertex, edge, and (100) facets on the shell, while still keeping the ORR activity on the active Pt(111) shell as high as that of Ni@Pt nanoparticles. Such behavior strongly depends on a direct interaction with the Ni interlayer. The results not only highlight the importance of interplay between surface strain on the shell and the interlayershell interaction in determining the durability and activity but also provide guidance on how to maximize the usage of Au to optimize the performance of coreshell (Pt) nanoparticles. As a result, such understanding has allowed us to discover a novel NiAu@Pt nanocatalyst for the ORR.

  1. Formation, Migration, and Reactivity of Au CO Complexes on Gold Surfaces

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Wang, Jun; McEntee, Monica; Tang, Wenjie; Neurock, Matthew; Baddorf, Arthur P.; Maksymovych, Petro; Yates, Jr, John T.

    2016-01-12

    Here, we report experimental as well as theoretical evidence that suggests Au CO complex formation upon the exposure of CO to active sites (step edges and threading dislocations) on a Au(111) surface. Room-temperature scanning tunneling microscopy (STM), X-ray photoelectron spectroscopy, transmission infrared spectroscopy, and density functional theory calculations point to Au CO complex formation and migration. Room-temperature STM of the Au(111) surface at CO pressures in the range from 10^ 8 to 10^ 4 Torr (dosage up to 10^6 langmuir) indicates Au atom extraction from dislocation sites of the herringbone reconstruction, mobile Au CO complex formation and diffusion, and Aumore » adatom cluster formation on both elbows and step edges on the Au surface. The formation and mobility of the Au CO complex result from the reduced Au Au bonding at elbows and step edges leading to stronger Au CO bonding and to the formation of a more positively charged CO (CO +) on Au. These studies indicate that the mobile Au CO complex is involved in the Au nanoparticle formation and reactivity, and that the positive charge on CO increases due to the stronger adsorption of CO at Au sites with lower coordination numbers.« less

  2. Study of requirements and performances of the electromagnetic calorimeter for the Mu2e experiment at Fermilab

    SciTech Connect (OSTI)

    Soleti, S.

    2015-06-15

    In this thesis we discuss the simulation and tests carried out for the optimization and design of the electromagnetic calorimeter for the Mu2e (Muon to electron conversion) experiment, which is a proposed experiment part of the Muon Campus hosted at Fermi National Accelerator Laboratory (FNAL) in Batavia, United States.

  3. THE LEGACY OF SCUPOL: 850 {mu}m IMAGING POLARIMETRY FROM 1997 TO 2005

    SciTech Connect (OSTI)

    Matthews, Brenda C.; McPhee, Christie A.; Fissel, Laura M.; Curran, Rachel L.

    2009-05-15

    SCUPOL, the polarimeter for SCUBA on the James Clerk Maxwell Telescope, was the most prolific thermal imaging polarimeter built to date. Between 1997 and 2005, observations of 104 regions were made at 850 {mu}m in the mapping mode. The instrument has produced {approx}50 refereed journal publications, and that number is still growing. We have systematically re-reduced all imaging polarimetry made in the standard 'jiggle-map' mode from the SCUBA archive (2800+ individual observations) to produce a catalog of SCUPOL images and tables. We present the results of our analysis with figures and data tables produced for all 83 regions where significant polarization was detected. In addition, the reduced data cubes and data tables can be accessed online. In many cases, the data included in this paper have been previously published elsewhere. However, this publication includes unpublished data sets, in whole or in part, toward 39 regions, including cores in {rho} Ophiuchus, Orion's OMC-2 region, several young stellar objects, and the galaxy M87.

  4. Thermal and Structural Analysis of Beamline Components in the Mu2e Experiment

    SciTech Connect (OSTI)

    Martin, Luke Daniel

    2016-01-01

    Fermi National Accelerator Laboratory will be conducting the high energy particle physics experiment Muons to Electrons (Mu2e). In this experiment, physicists will attempt to wit- ness and understand an ultra-rare process which is the conversion of a muon into the lighter mass electron, without creating additional neutrinos. The experiment is conducted by rst generating a proton beam which will be collided into a target within the production solenoid (PS). This creates a high intensity muon beam which passes through a transport solenoid (TS) and into the detector solenoid (DS). In the detector solenoid the muons will be stopped in an aluminum target and a series of detectors will measure the electrons produced. These components have been named the DS train since they are coupled and travel on a rail system when being inserted or extracted from the DS. To facilitate the installation and removal of the DS train, a set of external stands and a support stand for the instrumentation feed- through bulkhead (IFB) have been designed. Full analysis of safety factors and performance of these two designs has been completed. The detector solenoid itself will need to be main- tained to a temperature of 22°C 10°C. This will minimize thermal strain and ensure the accurate position of the components is maintained to the tolerance of 2 mm. To reduce the thermal gradient, a passive heating system has been developed and reported.

  5. Synchrotron Radiation {mu}-X Ray Fluorescence on Multicellular Tumor Spheroids

    SciTech Connect (OSTI)

    Burattini, E.; Cinque, G.; Bellisola, G.; Fracasso, G.; Colombatti, M.; Monti, F.

    2003-01-24

    Synchrotron Radiation micro X-Ray Fluorescence (SR {mu}-XRF) was applied for the first time to map the trace element content on Multicellular Tumor Spheroids (MTS), i.e. human cell clusters used as an in vitro model for testing micrometastases responses to antitumoral drugs. In particular, immunotoxin molecules composed of a carrier protein (Transferrin) bound to a powerful cytotoxin (Ricin A), were here considered as representatives of a class of therapheutic macromolecules used in cancer theraphy. Spheroids included in polyacrylamide gel and placed inside quartz capillaries were studied at the ESRF ID22 beamline using a 15 keV monochromatic photon microbeam. Elemental maps (of Fe, Cu, Zn and Pb) on four groups of spheroids grown under different conditions were studied: untreated, treated only with the carrier molecule or with the toxin alone, and with the complete immunotoxin molecule (carrier+toxin). The results indicate that the distribution of Zn and, to some extent, Cu in the spheroid cells is homogeneous and independent of the treatment type. Total Reflection X-Ray Fluorescence (TR-XRF) was also applied to quantify the average trace element content in the spheroids. Future developments of the technique are finally outlined on the basis of these preliminary results.

  6. Tracking Simulation of Third-Integer Resonant Extraction for Fermilab's Mu2e Experiment

    SciTech Connect (OSTI)

    Park, Chong Shik; Amundson, James; Michelotti, Leo

    2015-02-13

    The Mu2e experiment at Fermilab requires acceleration and transport of intense proton beams in order to deliver stable, uniform particle spills to the production target. To meet the experimental requirement, particles will be extracted slowly from the Delivery Ring to the external beamline. Using Synergia2, we have performed multi-particle tracking simulations of third-integer resonant extraction in the Delivery Ring, including space charge effects, physical beamline elements, and apertures. A piecewise linear ramp profile of tune quadrupoles was used to maintain a constant averaged spill rate throughout extraction. To study and minimize beam losses, we implemented and introduced a number of features, beamline element apertures, and septum plane alignments. Additionally, the RF Knockout (RFKO) technique, which excites particles transversely, is employed for spill regulation. Combined with a feedback system, it assists in fine-tuning spill uniformity. Simulation studies were carried out to optimize the RFKO feedback scheme, which will be helpful in designing the final spill regulation system.

  7. LUCIA - a new 1-7 keV {mu}-XAS Beamline

    SciTech Connect (OSTI)

    Janousch, M.; Schmidt, Th.; Wetter, R.; Grolimund, G.; Scheidegger, A.M.; Flank, A.-M.; Lagarde, P.; Cauchon, G.; Bac, S.; Dubuisson, J.M.

    2004-05-12

    LURE-SOLEIL (France) and the Swiss Light Source (SLS) are building together a new micro focused beamline for micro x-ray absorption spectroscopy and micro imaging. This line is designed to deliver a photon flux of the order of 1012 ph/sec on a 1 x 1 {mu}m spot within the energy domain of 0.8 to 7 keV. This beam line is being installed on the X07M straight section of SLS. The source is an APPLE II undulator with a period of 54 mm. The main advantage of this device lies in the delivery of any degree of polarization, linear or circular, over the whole energy range, without the need of a sample-position change. The monochromator will be a fixed exit double crystal equipped with 5 sets of crystals, thanks to the very narrow photon beam from the undulator ( Beryl, KTP, YB66, InSb(111), Si(111) ). The optics includes a first horizontal focusing mirror (spherical), which produces an intermediate source for the horizontal mirror of a Kirkpatrick-Baez (KB) system. The vertical mirror of the KB directly images the source. Finally, a low-pass double mirror filter insures a proper harmonic rejection.

  8. Dielectron Azimuthal Anisotropy at mid-rapidity in Au+Au collisions at root s=200GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adamczyk, L.

    2014-12-11

    We report on the first measurement of the azimuthal anisotropy (v₂) of dielectrons (e⁺e⁻ pairs) at mid-rapidity from √(sNN)=200 GeV Au + Au collisions with the STAR detector at the Relativistic Heavy Ion Collider (RHIC), presented as a function of transverse momentum (pT) for different invariant-mass regions. In the mass region Meeee<2.9GeV/c², the measured dielectron v₂ is consistent, within experimental uncertainties, with that from the cc¯ contributions.

  9. Low frequency noise in the unstable contact region of Au-to-Au microcontact for microelectromechanical system switches

    SciTech Connect (OSTI)

    Qiu, Haodong; Wang, Hong; Ke, Feixiang

    2014-06-23

    The noise behavior of Au-to-Au microcontact for microelectromechanical system switches has been experimentally studied in the unstable contact region. The results suggest that the electrical conduction remains nonmetallic at the initial stage during contact formation due to the existence of alien films, and traps in the alien layer located at the contact interface could play an important role in determining the conduction noise. The conduction fluctuation induced by electron trapping-detrapping associated with the hydrocarbon layer is found to be an intrinsic noise source contributing to the low frequency noise in the unstable contact region.

  10. ΛΛ correlation function in Au + Au collisions at √sNN = 200 GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adamczyk, L.

    2015-01-12

    In this study, we present ΛΛ correlation measurements in heavy-ion collisions for Au+Au collisions at √sNN = 200 GeV using the STAR experiment at the Relativistic Heavy-Ion Collider (RHIC). The Lednický-Lyuboshitz analytical model has been used to fit the data to obtain a source size, a scattering length and an effective range. Implications of the measurement of the ΛΛ correlation function and interaction parameters for di-hyperon searches are discussed.

  11. Gold-rich R3Au7Sn3: Establishing the interdependence between...

    Office of Scientific and Technical Information (OSTI)

    Gold-rich R3Au7Sn3: Establishing the interdependence between electronic features and physical properties Title: Gold-rich R3Au7Sn3: Establishing the interdependence between ...

  12. Gold-rich R3Au7Sn3: Establishing the interdependence between...

    Office of Scientific and Technical Information (OSTI)

    Gold-rich R3Au7Sn3: Establishing the interdependence between electronic features and physical properties Citation Details In-Document Search Title: Gold-rich R3Au7Sn3: Establishing ...

  13. The effect of Au and Ni doping on the heavy fermion state of...

    Office of Scientific and Technical Information (OSTI)

    We have probed the effect of doping CePtZn with Au and Ni and also investigated in detail the magnetic behavior of the iso-structural CeAuZn. A magnetic ground state is observed in ...

  14. AuRu/AC as an effective catalyst for hydrogenation reactions

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Villa, Alberto; Chan-Thaw, Carine E.; Campisi, Sebastiano; Bianchi, Claudia L.; Wang, Di; Kotula, Paul G.; Kübel, Christian; Prati, Laura

    2015-03-23

    AuRu bimetallic catalysts have been prepared by sequential deposition of Au on Ru or vice versa obtaining different nanostructures: when Ru has been deposited on Au, a Aucore–Rushell has been observed, whereas the deposition of Au on Ru leads to a bimetallic phase with Ru enrichment on the surface. In the latter case, the unexpected Ru enrichment could be attributed to the weak adhesion of Ru on the carbon support, thus allowing Ru particles to diffuse on Au particles. Both structures result very active in catalysing the liquid phase hydrogenolysis of glycerol and levulinic acid but the activity, the selectivitymore » and the stability depend on the structure of the bimetallic nanoparticles. Ru@Au/AC core–shell structure mostly behaved as the monometallic Ru, whereas the presence of bimetallic AuRu phase in Au@Ru/AC provides a great beneficial effect on both activity and stability.« less

  15. ARM Climate Modeling Best Estimate From Darwin, AU (ARMBE-ATM...

    Office of Scientific and Technical Information (OSTI)

    Darwin, AU (ARMBE-ATM TWPC3) Title: ARM Climate Modeling Best Estimate From Darwin, AU (ARMBE-ATM TWPC3) The ARM CMBE-ATM Xie, McCoy, Klein et al. data file contains a best ...

  16. Observation of dynamic water microadsorption on Au surface

    SciTech Connect (OSTI)

    Huang, Xiaokang, E-mail: xiaokang.huang@tqs.com; Gupta, Gaurav; Gao, Weixiang; Tran, Van; Nguyen, Bang; McCormick, Eric; Cui, Yongjie; Yang, Yinbao; Hall, Craig; Isom, Harold [TriQuint Semiconductor, Inc., 500 W Renner Road, Richardson, Texas 75080 (United States)

    2014-05-15

    Experimental and theoretical research on water wettability, adsorption, and condensation on solid surfaces has been ongoing for many decades because of the availability of new materials, new detection and measurement techniques, novel applications, and different scales of dimensions. Au is a metal of special interest because it is chemically inert, has a high surface energy, is highly conductive, and has a relatively high melting point. It has wide applications in semiconductor integrated circuitry, microelectromechanical systems, microfluidics, biochips, jewelry, coinage, and even dental restoration. Therefore, its surface condition, wettability, wear resistance, lubrication, and friction attract a lot of attention from both scientists and engineers. In this paper, the authors experimentally investigated Au{sub 2}O{sub 3} growth, wettability, roughness, and adsorption utilizing atomic force microscopy, scanning electron microscopy, reflectance spectrometry, and contact angle measurement. Samples were made using a GaAs substrate. Utilizing a super-hydrophilic Au surface and the proper surface conditions of the surrounding GaAs, dynamic microadsorption of water on the Au surface was observed in a clean room environment. The Au surface area can be as small as 12??m{sup 2}. The adsorbed water was collected by the GaAs groove structure and then redistributed around the structure. A model was developed to qualitatively describe the dynamic microadsorption process. The effective adsorption rate was estimated by modeling and experimental data. Devices for moisture collection and a liquid channel can be made by properly arranging the wettabilities or contact angles of different materials. These novel devices will be very useful in microfluid applications or biochips.

  17. Growth of Long Range Forward-Backward Multiplicity Correlations with Centrality in Au+Au Collisions at sqrt sNN = 200 GeV

    SciTech Connect (OSTI)

    STAR Collaboration; Abelev, Betty

    2010-07-05

    Forward-backward multiplicity correlation strengths have been measured with the STAR detector for Au+Au and p+p collisions at {radical}s{sub NN} = 200 GeV. Strong short and long range correlations (LRC) are seen in central Au+Au collisions. The magnitude of these correlations decrease with decreasing centrality until only short range correlations are observed in peripheral Au+Au collisions. Both the Dual Parton Model (DPM) and the Color Glass Condensate (CGC) predict the existence of the long range correlations. In the DPM the fluctuation in the number of elementary (parton) inelastic collisions produces the LRC. In the CGC longitudinal color flux tubes generate the LRC. The data is in qualitative agreement with the predictions from the DPM and indicates the presence of multiple parton interactions.

  18. Local spectroscopy of a kondo impurity: Co on Au(111)

    SciTech Connect (OSTI)

    Madhavan, V.; Chen, W.; Jamneala, T.; Crommie, M.F.; Wingreen, N.S.

    2001-07-15

    We present a detailed study of the local electronic properties of the Kondo system formed from cobalt adatoms deposited onto Au(111) at a temperature of 6.6 K. Cryogenic scanning-tunneling spectroscopy was used to observe impurity-induced resonances at the Fermi energy and at the Au(111) surface-state band edge. The line shape of the Fermi-energy resonance, identified as a Kondo resonance, is observed to vary with lateral position from the impurity center and with impurity binding position on the reconstructed Au(111) surface. Little vertical dependence is seen in the resonance line shape for positions above the center of the impurity. Interaction effects between Kondo impurities are observed to remain small as cobalt coverage is increased up to 1 ML on the gold surface. The Kondo resonance is shown theoretically to be a member of a general class of Fano resonances arising from the interaction of a discrete impurity state with a conduction-electron continuum. The asymmetric line shape of the resonance thus reflects quantum interference between the d orbital and continuum conduction electron channels, as well as their coupling to the STM tip.

  19. Dielectron Azimuthal Anisotropy at mid-rapidity in Au+Au collisions at root s=200GeV

    SciTech Connect (OSTI)

    Adamczyk, L.

    2014-12-11

    We report on the first measurement of the azimuthal anisotropy (v₂) of dielectrons (e⁺e⁻ pairs) at mid-rapidity from √(sNN)=200 GeV Au + Au collisions with the STAR detector at the Relativistic Heavy Ion Collider (RHIC), presented as a function of transverse momentum (pT) for different invariant-mass regions. In the mass region Mee<1.1 GeV/c² the dielectron v₂ measurements are found to be consistent with expectations from π⁰,η,ω, and Φ decay contributions. In the mass region 1.1ee<2.9GeV/c², the measured dielectron v₂ is consistent, within experimental uncertainties, with that from the cc¯ contributions.

  20. Dielectron Azimuthal Anisotropy at mid-rapidity in Au+Au collisions at root s=200GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adamczyk, L.

    2014-12-11

    We report on the first measurement of the azimuthal anisotropy (v₂) of dielectrons (e⁺e⁻ pairs) at mid-rapidity from √(sNN)=200 GeV Au + Au collisions with the STAR detector at the Relativistic Heavy Ion Collider (RHIC), presented as a function of transverse momentum (pT) for different invariant-mass regions. In the mass region Mee<1.1 GeV/c² the dielectron v₂ measurements are found to be consistent with expectations from π⁰,η,ω, and Φ decay contributions. In the mass region 1.1ee<2.9GeV/c², the measured dielectron v₂ is consistent, within experimental uncertainties, with that from the cc¯ contributions.

  1. Dielectron Azimuthal Anisotropy at mid-rapidity in Au+Au collisions at root s=200GeV

    SciTech Connect (OSTI)

    Adamczyk, L.; STAR Collaboration

    2014-12-01

    We report on the first measurement of the azimuthal anisotropy (v?) of dielectrons (e?e? pairs) at mid-rapidity from ?(sNN)=200 GeV Au + Au collisions with the STAR detector at the Relativistic Heavy Ion Collider (RHIC), presented as a function of transverse momentum (pT) for different invariant-mass regions. In the mass region Mee<1.1 GeV/c the dielectron v? measurements are found to be consistent with expectations from ??,?,?, and ? decay contributions. In the mass region 1.1ee<2.9GeV/c, the measured dielectron v? is consistent, within experimental uncertainties, with that from the cc contributions.

  2. Ag@Au concave cuboctahedra: A unique probe for monitoring Au-catalyzed reduction and oxidation reactions by surface-enhanced Raman spectroscopy

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zhang, Jiawei; Winget, Sarah A.; Wu, Yiren; Su, Dong; Sun, Xiaojun; Xie, Zhao -Xiong; Qin, Dong

    2016-01-26

    In this paper, we report a facile synthesis of Ag@Au concave cuboctahedra by titrating aqueous HAuCl4 into a suspension of Ag cuboctahedra in the presence of ascorbic acid (AA), NaOH, and poly(vinylpyrrolidone) (PVP) at room temperature. Initially, the Au atoms derived from the reduction of Au3+ by AA are conformally deposited on the entire surface of a Ag cuboctahedron. Upon the formation of a complete Au shell, however, the subsequently formed Au atoms are preferentially deposited onto the Au{100} facets, resulting in the formation of a Ag@Au cuboctahedron with concave structures at the sites of {111} facets. The concave cuboctahedramore » embrace excellent SERS activity that is more than 70-fold stronger than that of the original Ag cuboctahedra at an excitation wavelength of 785 nm. The concave cuboctahedra also exhibit remarkable stability in the presence of an oxidant such as H2O2 because of the protection by a complete Au shell. These two unique attributes enable in-situ SERS monitoring of the reduction of 4-nitrothiophenol (4-NTP) to 4-aminothiophenol (4-ATP) by NaBH4 through a 4,4'-dimercaptoazobenzene (trans-DMAB) intermediate and the subsequent oxidation of 4-ATP back to trans-DMAB upon the introduction of H2O2.« less

  3. Formation of Pd/Au Nanostructures from Pd Nanowires via Galvanic Replacement Reaction

    SciTech Connect (OSTI)

    Teng,X.; Wang, Q.; Liu, P.; Han, W.; Frenkel, A.; Wen, W.; Marinkovic, N.; Hanson, J.; Rodriguez, J.

    2008-01-01

    Bimetallic nanostructures with non-random metal atoms distribution are very important for various applications. To synthesize such structures via benign wet chemistry approach remains challenging. This paper reports a synthesis of a Au/Pd alloy nanostructure through the galvanic replacement reaction between Pd ultrathin nanowires (2.4 {+-} 0.2 nm in width, over 30 nm in length) and AuCl3 in toluene. Both morphological and structural changes were monitored during the reaction up to 10 h. Continuous changes of chemical composition and crystalline structure from Pd nanowires to Pd68Au32 and Pd45Au55 alloys, and to Au nanoparticles were observed. More interestingly, by using combined techniques such as high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), energy dispersive X-ray spectrometry (EDS), UV-vis absorption, and extended X-ray absorption fine structure (EXAFS) spectroscopy, we found the formation of Pd68Au32 non-random alloy with Au-rich core and Pd-rich shell, and random Pd45Au55 alloy with uniformly mixed Pd and Au atom inside the nanoparticles, respectively. Density functional theory (DFT) calculations indicated that alkylamine will strongly stabilize Pd to the surface, resulting in diffusion of Au atoms into the core region to form a non-random alloy. We believe such benign synthetic techniques can also enable the large scale preparation of various types of non-random alloys for several technically important catalysis applications.

  4. Structural and phonon transmission study of Ge-Au-Ge eutectically bonded interfaces

    SciTech Connect (OSTI)

    Knowlton, W.B. |

    1995-07-01

    This thesis presents a structural analysis and phonon transparency investigation of the Ge-Au-Ge eutectic bond interface. Interface development was intended to maximize the interfacial ballistic phonon transparency to enhance the detection of the dark matter candidate WIMPs. The process which was developed provides an interface which produces minimal stress, low amounts of impurities, and insures Ge lattice continuity through the interface. For initial Au thicknesses of greater than 1,000 {angstrom} Au per substrate side, eutectic epitaxial growth resulted in a Au dendritic structure with 95% cross sectional and 90% planar Au interfacial area coverages. In sections in which Ge bridged the interface, lattice continuity across the interface was apparent. Epitaxial solidification of the eutectic interface with initial Au thicknesses < 500 A per substrate side produced Au agglomerations thereby reducing the Au planar interfacial area coverage to as little as 30%. The mechanism for Au coalescence was attributed to lateral diffusion of Ge and Au in the liquid phase during solidification. Phonon transmission studies were performed on eutectic interfaces with initial Au thicknesses of 1,000 {angstrom}, 500 {angstrom}, and 300 {angstrom} per substrate side. Phonon imaging of eutectically bonded samples with initial Au thicknesses of 300 {angstrom}/side revealed reproducible interfacial percent phonon transmissions from 60% to 70%. Line scan phonon imaging verified the results. Phonon propagation TOF spectra distinctly showed the predominant phonon propagation mode was ballistic. This was substantiated by phonon focusing effects apparent in the phonon imaging data. The degree of interface transparency to phonons and resulting phonon propagation modes correlate with the structure of the interface following eutectic solidification. Structural studies of samples with initial Au thickness of 1,000 {angstrom}/side appear to correspond with the phonon transmission study.

  5. Identification of {gamma} rays from {sup 172}Au and {alpha} decays of {sup 172}Au, {sup 168}Ir, and {sup 164}Re

    SciTech Connect (OSTI)

    Hadinia, B.; Cederwall, B.; Andgren, K.; Baeck, T.; Johnson, A.; Khaplanov, A.; Wyss, R.; Page, R. D.; Grahn, T.; Paul, E. S.; Sandzelius, M.; Scholey, C.; Greenlees, P. T.; Jakobsson, U.; Jones, P. M.; Julin, R.; Juutinen, J.; Ketelhut, S.; Leino, M.; Nyman, M.

    2009-12-15

    The very neutron deficient odd-odd nucleus {sup 172}Au was studied in reactions of 342 and 348 MeV {sup 78}Kr beams with an isotopically enriched {sup 96}Ru target. The {alpha} decays previously reported for {sup 172}Au were confirmed and the decay chain extended down to {sup 152}Tm through the discovery of a new {alpha}-decaying state in {sup 164}Re[E{sub {alpha}}=5623(10) keV; t{sub 1/2}=864{sub -110}{sup +150} ms; b{sub {alpha}}=3(1)%]. Fine structure in these {alpha} decays of {sup 172}Au and {sup 168}Ir were identified. A new {alpha}-decaying state was also observed and assigned as the ground state in {sup 172}Au[E{sub {alpha}}=6762(10) keV; t{sub 1/2}=22{sub -5}{sup +6} ms]. This decay chain was also correlated down to {sup 152}Tm through previously reported {alpha} decays. Prompt {gamma} rays from excited states in {sup 172}Au have been identified using the recoil-decay tagging technique. The partial level scheme constructed for {sup 172}Au indicates that it has an irregular structure. Possible configurations of the {alpha}-decaying states in {sup 172}Au are discussed in terms of the systematics of nuclei in this region and total Routhian surface calculations.

  6. Gold-rich R3Au7Sn3: Establishing the interdependence between electronic

    Office of Scientific and Technical Information (OSTI)

    features and physical properties (Journal Article) | SciTech Connect Journal Article: Gold-rich R3Au7Sn3: Establishing the interdependence between electronic features and physical properties Citation Details In-Document Search Title: Gold-rich R3Au7Sn3: Establishing the interdependence between electronic features and physical properties Two new polar intermetallic compounds Y3Au7Sn3 (I) and Gd3Au7Sn3 (II) have been synthesized and their structures have been determined by single crystal X-ray

  7. Microwave Synthesis of Au?Rh Core?Shell Nanoparticles and Implications...

    Office of Scientific and Technical Information (OSTI)

    Microwave Synthesis of Au?Rh Core?Shell Nanoparticles and Implications of the Shell Thickness in Hydrogenation Catalysis Citation Details In-Document Search Title: Microwave ...

  8. AuRu/AC as an effective catalyst for hydrogenation reactions

    SciTech Connect (OSTI)

    Villa, Alberto; Chan-Thaw, Carine E.; Campisi, Sebastiano; Bianchi, Claudia L.; Wang, Di; Kotula, Paul G.; Kübel, Christian; Prati, Laura

    2015-03-23

    AuRu bimetallic catalysts have been prepared by sequential deposition of Au on Ru or vice versa obtaining different nanostructures: when Ru has been deposited on Au, a Aucore–Rushell has been observed, whereas the deposition of Au on Ru leads to a bimetallic phase with Ru enrichment on the surface. In the latter case, the unexpected Ru enrichment could be attributed to the weak adhesion of Ru on the carbon support, thus allowing Ru particles to diffuse on Au particles. Both structures result very active in catalysing the liquid phase hydrogenolysis of glycerol and levulinic acid but the activity, the selectivity and the stability depend on the structure of the bimetallic nanoparticles. Ru@Au/AC core–shell structure mostly behaved as the monometallic Ru, whereas the presence of bimetallic AuRu phase in Au@Ru/AC provides a great beneficial effect on both activity and stability.

  9. Examination of charge transfer in Au/YSZ for high-temperature optical gas sensing

    SciTech Connect (OSTI)

    Baltrus, John P.; Ohodnicki, Paul R.

    2014-01-01

    Au-nanoparticle incorporated oxide thin film materials demonstrate significant promise as functionalsensor materials for high temperature optical gas sensing in severe environments relevant for fossil andnuclear based power generation. The Au/yttria-stabilized zirconia (YSZ) system has been extensivelystudied in the literature and serves as a model system for fundamental investigations that seek to betterunderstand the mechanistic origin of the plasmonic gas sensing response. In this work, X-ray photoelec-tron spectroscopy techniques are applied to Au/YSZ films in an attempt to provide further experimentalevidence for a proposed sensing mechanism involving a change in free carrier density of Au nanoparticles due to charge transfer.

  10. Gold-rich R3Au7Sn3: Establishing the interdependence between electronic

    Office of Scientific and Technical Information (OSTI)

    features and physical properties (Journal Article) | DOE PAGES Gold-rich R3Au7Sn3: Establishing the interdependence between electronic features and physical properties Title: Gold-rich R3Au7Sn3: Establishing the interdependence between electronic features and physical properties Two new polar intermetallic compounds Y3Au7Sn3 (I) and Gd3Au7Sn3 (II) have been synthesized and their structures have been determined by single crystal X-ray diffraction (P63/m; Z = 2, a = 8.148(1)/8.185(3), and c =

  11. The effect of Au and Ni doping on the heavy fermion state of the Kondo

    Office of Scientific and Technical Information (OSTI)

    lattice antiferromagnet CePtZn (Journal Article) | SciTech Connect The effect of Au and Ni doping on the heavy fermion state of the Kondo lattice antiferromagnet CePtZn Citation Details In-Document Search Title: The effect of Au and Ni doping on the heavy fermion state of the Kondo lattice antiferromagnet CePtZn We have probed the effect of doping CePtZn with Au and Ni and also investigated in detail the magnetic behavior of the iso-structural CeAuZn. A magnetic ground state is observed in

  12. Metamorphic approach to single quantum dot emission at 1.55 {mu}m on GaAs substrate

    SciTech Connect (OSTI)

    Semenova, E. S.; Hostein, R.; Patriarche, G.; Mauguin, O.; Largeau, L.; Robert-Philip, I.; Beveratos, A.; Lemaitre, A.

    2008-05-15

    We report on the fabrication and the characterization of InAs quantum dots (QDs) embedded in an indium rich In{sub 0.42}Ga{sub 0.58}As metamorphic matrix grown on a GaAs substrate. Growth conditions were chosen so as to minimize the number of threading dislocations and other defects produced during the plastic relaxation. Sharp and bright lines, originating from the emission of a few isolated single quantum dots, were observed in microphotoluminescence around 1.55 {mu}m at 5 K. They exhibit, in particular, a characteristic exciton/biexciton behavior. These QDs could offer an interesting alternative to other approaches as InAs/InP QDs for the realization of single photon emitters at telecom wavelengths.

  13. Mechanism of ternary breakup in the reaction {sup 197}Au+{sup 197}Au at 15A MeV

    SciTech Connect (OSTI)

    Tian Junlong; Wu Xizhen; Li Zhuxia; Zhao Kai; Zhang Yingxun; Li Xian; Yan Shiwei

    2010-11-15

    The mechanism of the ternary breakup of the very heavy system {sup 197}Au+{sup 197}Au at an energy of 15A MeV has been studied by using the improved quantum molecular dynamics model. The calculation results reproduce the characteristic features in ternary breakup events explored in a series of experiments; i.e., the masses of three fragments are comparable in size and the very fast, nearly collinear breakup of the colliding system is dominant in the ternary breakup events. Further, the evolution of the time scales of different ternary reaction modes and the behavior of mass distributions of three fragments with impact parameters are studied. The time evolution of the configurations of the composite reaction systems is also studied. We find that for most of the ternary breakup events with the features found in the experiments, the configuration of the composite system has two-preformed-neck shape. The study shows that those ternary breakup events having the characteristic features found in the experiments happen at relatively small impact parameter reactions, but not at peripheral reactions. The ternary breakup reaction at peripheral reactions belongs to binary breakup with a neck emission.

  14. Identified Hadron Compositions in p+p and Au+Au Collisions at High Transverse Momenta at √(sNN)=200 GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alakhverdyants, A. V.; Alekseev, I.; Alford, J.; Anderson, B. D.; Anson, C. D.; Arkhipkin, D.; Averichev, G. S.; et al

    2012-02-14

    We report transverse momentum (pT≤15 GeV/c) spectra of π±, K±, p, p̄, K0S, and ρ⁰ at midrapidity in p+p and Au+Au collisions at √(sNN)=200 GeV. Perturbative QCD calculations are consistent with π± spectra in p+p collisions but do not reproduce K and p(p̄) spectra. The observed decreasing antiparticle-to-particle ratios with increasing pT provide experimental evidence for varying quark and gluon jet contributions to high-pT hadron yields. The relative hadron abundances in Au+Au at pT ≳ 8 GeV/c are measured to be similar to the p+p results, despite the expected Casimir effect for parton energy loss.

  15. Identified Hadron Compositions in p+p and Au+Au Collisions at High Transverse Momenta at ?(sNN)=200 GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alakhverdyants, A. V.; Alekseev, I.; Alford, J.; Anderson, B. D.; Anson, C. D.; Arkhipkin, D.; Averichev, G. S.; et al

    2012-02-14

    We report transverse momentum (pT?15 GeV/c) spectra of ?, K, p, p?, K0S, and ?? at midrapidity in p+p and Au+Au collisions at ?(sNN)=200 GeV. Perturbative QCD calculations are consistent with ? spectra in p+p collisions but do not reproduce K and p(p?) spectra. The observed decreasing antiparticle-to-particle ratios with increasing pT provide experimental evidence for varying quark and gluon jet contributions to high-pT hadron yields. The relative hadron abundances in Au+Au at pT ? 8 GeV/c are measured to be similar to the p+p results, despite the expected Casimir effect for parton energy loss.

  16. Thermal nature of charmonium transverse momentum spectra from Au-Au collisions at the highest energies available at the BNL Relativistic Heavy Ion Collider (RHIC)

    SciTech Connect (OSTI)

    Akkelin, S. V.; Sinyukov, Yu. M.; Braun-Munzinger, P.

    2010-03-15

    We analyze the transverse momentum distribution of J/psi mesons produced in Au+Au collisions at the top RHIC energy within a blast-wave model that accounts for a possible inhomogeneity of the charmonium distribution and/or flow fluctuations. The results imply that the transverse momentum spectra of J/psi, phi, and OMEGA hadrons measured at the RHIC can be described well if kinetic freeze-out takes place just after chemical freeze-out for these particles.

  17. Experimental search for the radiative capture reaction d + d {yields} {sup 4}He + {gamma} from the dd{mu} muonic molecule state J = 1

    SciTech Connect (OSTI)

    Baluev, V. V.; Bogdanova, L. N.; Bom, V. R.; Demin, D. L.; Eijk, C. W. E. van; Filchenkov, V. V.; Grafov, N. N.; Grishechkin, S. K.; Gritsaj, K. I.; Konin, A. D.; Mikhailyukov, K. L.; Rudenko, A. I.; Vinogradov, Yu. I.; Volnykh, V. P.; Yukhimchuk, A. A.; Yukhimchuk, S. A.

    2011-07-15

    A search for the muon-catalyzed fusion reaction d + d {yields} {sup 4}He + {gamma} in the dd{mu} muonic molecule was performed using the experimental installation TRITON with BGO detectors for {gamma}-quanta. A high-pressure target filled with deuterium was exposed to the negative muon beam of the JINR Phasotron to detect {gamma}-quanta with the energy 23.8 MeV. An experimental estimation for the yield of radiative deuteron capture from the dd{mu} state J = 1 was obtained at the level of {eta}{sub {gamma}} {<=} 8 Multiplication-Sign 10{sup -7} per fusion.

  18. Interface Reactions and Electrical Characteristics of Au/GaSb Contacts

    SciTech Connect (OSTI)

    H. Ehsani; R.J. Gutmann; G.W. Charache

    2000-07-07

    The reaction of Au with GaSb occurs at a relatively low temperature (100 C). Upon annealing, a AuSb{sub 2} compound and several Au-Ga phases are produced. Phase transitions occur toward higher Ga concentration with increasing annealing temperatures. Furthermore, the depth of the contact also increases with increased annealing temperature. They found that the AuSb{sub 2} compound forms on the GaSb surface, with the compound crystal partially ordered with respect to the substrate. The transition of Schottky- to ohmic-contact behavior in Au/n-type GaSb occurs simultaneously with the formation of the AuGa compound at about a 250 C annealing temperature. This ohmic contact forms without the segregation of dopants at the metallic compound/GaSb interface. Therefore it is postulated that transition from Schottky- to ohmic-contact behavior is obtained through a series of tunneling transitions of electrons through defects in the depletion region in the Au/n-type GaSb contacts. Contact resistivities of 6-7 x 10{sup -6} {Omega}-cm{sup 2} were obtained with the annealing temperature between 300 and 350 C for 30 seconds. In Au/p-type GaSb contacts, the resistivity was independent of the annealing temperature. This suggested that the carrier transport in p-type contact dominated by thermionic emission.

  19. Multifunctional hybrid Fe2O3-Au nanoparticles for efficient plasmonic heating

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Murph, Simona E. Hunyadi; Larsen, George K.; Lascola, Robert J.

    2016-02-20

    We describe the synthesis and properties of multifunctional Fe2O3-Au nanoparticles produced by a wet chemical approach and investigate their photothermal properties using laser irradiation. Here, the composite Fe2O3-Au nanoparticles retain the properties of both materials, creating a multifunctional structure with excellent magnetic and plasmonic properties.

  20. Nanoscale mapping of plasmon and exciton in ZnO tetrapods coupled with Au nanoparticles

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Bertoni, Giovanni; Fabbri, Filippo; Villani, Marco; Lazzarini, Laura; Turner, Stuart; Van Tendeloo, Gustaaf; Calestani, Davide; Gradečak, Silvija; Zappettini, Andrea; Salviati, Giancarlo

    2016-01-12

    Metallic nanoparticles can be used to enhance optical absorption or emission in semiconductors, thanks to a strong interaction of collective excitations of free charges (plasmons) with electromagnetic fields. Herein we present direct imaging at the nanoscale of plasmon-exciton coupling in Au/ZnO nanostructures by combining scanning transmission electron energy loss and cathodoluminescence spectroscopy and mapping. The Au nanoparticles (~30 nm in diameter) are grown in-situ on ZnO nanotetrapods by means of a photochemical process without the need of binding agents or capping molecules, resulting in clean interfaces. Interestingly, the Au plasmon resonance is localized at the Au/vacuum interface, rather than presentingmore » an isotropic distribution around the nanoparticle. Moreover, on the contrary, a localization of the ZnO signal has been observed inside the Au nanoparticle, as also confirmed by numerical simulations.« less

  1. The low-temperature form of calcium gold stannide, CaAuSn

    SciTech Connect (OSTI)

    Lin, Qisheng; Corbett, John D.

    2014-07-19

    The EuAuGe-type CaAuSn phase has been synthesized and single-crystal X-ray diffraction analysis reveals that it has an orthorhombic symmetry (space group Imm2), with a = 4.5261 (7) , b = 7.1356 (11) and c = 7.8147 (11) . The structure features puckered layers that are connected by homoatomic Au-Au and Sn-Sn interlayer bonds. This structure is one of the two parent structures of its high-temperature polymorph (ca 873 K), which is an intergrowth structure of the EuAuGe- and SrMgSi-type structures in a 2:3 ratio.

  2. Nuclear matter effects on J/? production in asymmetric Cu+Au collisions at ?SNN=200 GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adare, A.

    2014-12-18

    We report on J/? production from asymmetric Cu+Au heavy-ion collisions at ?sNN =200 GeV at the Relativistic Heavy Ion Collider at both forward (Cu-going direction) and backward (Au-going direction) rapidities. The nuclear modification of J/? yields in Cu+Au collisions in the Au-going direction is found to be comparable to that in Au+Au collisions when plotted as a function of the number of participating nucleons. In the Cu-going direction, J/? production shows a stronger suppression. This difference is comparable in magnitude and has the same sign as the difference expected from shadowing effects due to stronger low-x gluon suppression in themorelarger Au nucleus. The relative suppression is opposite to that expected from hot nuclear matter dissociation, since a higher energy density is expected in the Au-going direction.less

  3. Measurements of dielectron production in Au + Au collisions at sNN=200 GeV from the STAR experiment

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alekseev, I.; Alford, J.; Aparin, A.; Arkhipkin, D.; Aschenauer, E. C.; et al

    2015-08-24

    We report on measurements of dielectron (e⁺e⁻) production in Au+Au collisions at a center-of-mass energy of 200 GeV per nucleon-nucleon pair using the STAR detector at RHIC. Systematic measurements of the dielectron yield as a function of transverse momentum (pT) and collision centrality show an enhancement compared to a cocktail simulation of hadronic sources in the low invariant-mass region (Mee < 1GeV/c2). This enhancement cannot be reproduced by the ρ-meson vacuum spectral function. In minimum-bias collisions, in the invariant-mass range of 0.30 – 0.76GeV/c², integrated over the full pT acceptance, the enhancement factor is 1.76±0.06(stat.)±0.26(sys.)±0.29(cocktail). The enhancement factor exhibits weakmore » centrality and pT dependence in STAR's accessible kinematic regions, while the excess yield in this invariant-mass region as a function of the number of participating nucleons follows a power-law shape with a power of 1.44±0.10. Models that assume an in-medium broadening of the ρ-meson spectral function consistently describe the observed excess in these measurements. In addition, we report on measurements of ω- and Φ-meson production through their e⁺e⁻ decay channel. These measurements show good agreement with Tsallis blast-wave model predictions, as well as, in the case of the Φ meson, results through its K⁺K⁻ decay channel. In the intermediate invariant-mass region (1.1 < Mee < 3GeV/c²), we investigate the spectral shapes from different collision centralities. Physics implications for possible in-medium modification of charmed hadron production and other physics sources are discussed.« less

  4. Glycerol Hydrogenolysis on Carbon-Supported PtRu and AuRu Bimetallic Catalysts

    SciTech Connect (OSTI)

    Maris,E.; Ketchie, W.; Murayama, M.; Davis, R.

    2007-01-01

    Bimetallic PtRu and AuRu catalysts were prepared by a surface redox method in which Pt or Au was deposited onto the surface of carbon-supported Ru nanoparticles with an average diameter of 2-3 nm. Characterization by H2 chemisorption, analytical TEM, and X-ray absorption spectroscopy at the Ru K-edge, Pt LIII-edge, and Au LIII-edge confirmed that Pt and Au were successfully deposited onto Ru without disrupting the Ru particles. Depression of the ethane hydrogenolysis rate over Ru after addition of Au provided further evidence of successful deposition. The bimetallic particles were subsequently evaluated in the aqueous-phase hydrogenolysis of glycerol at 473 K and 40 bar H2 at neutral and elevated pH. Although monometallic Pt and Ru exhibited different activities and selectivities to products, the bimetallic PtRu catalyst functioned more like Ru. A similar result was obtained for the AuRu bimetallic catalyst. The PtRu catalyst appeared to be stable under the aqueous-phase reaction conditions, whereas the AuRu catalyst was altered by the harsh conditions. Gold appeared to migrate off the Ru and agglomerate on the carbon during the reaction in liquid water.

  5. Effects of the proximity of Au nanoparticles on magnetic and transport properties of LSMO ultrathin layers

    SciTech Connect (OSTI)

    Brivio, S.; Magen Dominguez, Cesar; Sidorenko, A; Petti, D.; Cantoni, M.; Finazzi, M; Ciccacci, F; Renzi, R; Varela del Arco, Maria; Picozzi, S.; Bertacco, R.

    2010-01-01

    The effect of the proximity of Au nanoparticles on the transport and magnetic properties of ultrathin La2/3Sr1/3MnO3 (LSMO) films has been investigated. We find a huge increase of the resistivity of the manganite (by four orders of magnitude for a Au nominal thickness of 2 nm), which is accompanied by a strong decrease of the Curie temperature. A combined scanning transmission electron microscopy and electron energy loss spectroscopy (STEM-EELS) analysis shows that interfaces are coherent and atomically sharp, and that the structural quality is very high. On the other end, a strong reduction of the Mn oxidation state is seen upon Au capping. NMR data show a strong attenuation of the double exchange signal upon formation of Au nanoparticles. Ab-initio calculations indicate a negligible influence of Au on LSMO at an ideal interface, with the LSMO surface magnetic and electronic properties essentially unchanged upon creation of the Au/LSMO interface. In view of these calculations, the experimental results cannot be explained in terms of purely electrostatic effects induced by the proximity of a noble metal. Here we propose that the main driving force underlying the observed change in physical properties is the high reactivity of Au nanoparticles which can locally pump oxygen from the manganite, thus favouring a phase separation ensuing from O inhomogeneity which deteriorates the transport and electrical properties.

  6. MeV Au Ion Irradiation in Silicon and Nanocrystalline Zirconia Film Deposited on Silicon Substrate

    SciTech Connect (OSTI)

    Chang, Yongqin; Zhang, Yanwen; Zhu, Zihua; Edmondson, Philip D.; Weber, William J.

    2012-09-01

    Nanocrystalline zirconia (ZrO2) film with thickness of 305 nm deposited on a silicon substrate was irradiated with 2 MeV Au ions to different fluences at different temperatures. The implanted ion profiles were measured by time-of-flight secondary ion mass spectrometry (ToF-SIMS) and simulated using the stopping and range of ions inmatter (SRIM) code, respectively. The experimental results show that a large fraction of the incident Au ions penetrates through the ZrO2 film and are deposited into the Si substrate. At the interface of ZrO2 and Si, a sudden decrease of Au concentration is observed due to the much larger scattering cross section of Au in ZrO2 than in Si. The depth profile of the Au ions is measured in both the ZrO2 films and the Si substrates, and the results show that the Au distribution profiles do not exhibit a dependence on irradiation temperature. The local Au concentration increases proportionally with the irradiation fluence, suggesting that no thermal or irradiation-induced redistribution of the implanted Au ions. However, the Au concentration in the ZrO2 films, as determined by SIMS, is considerably lower than that predicted by the SRIM results, and the penetration depth from the SIMS measurements is much deeper than that from the SRIM predictions. These observations can be explained by an overestimation of the electronic stopping power, used in the SRIM program, for heavy incident ions in light targets. Over-estimation of the heavy-ion electronic stopping power may lead to errors in local dose calculation and underestimation of the projected range of slow heavy ions in targets that contain light elements. A quick estimate based on a reduced target density may be used to compensate the overestimation of the electronic stopping power in the SRIM program to provide better ion profile prediction.

  7. MeV Au Ion Irradiation in Silicon and Nanocrystalline Zirconia Film Deposited on Silicon Substrate

    SciTech Connect (OSTI)

    Chang, Yongqin; Zhang, Yanwen; Zhu, Zihua; Edmondson, Dr. Philip; Weber, William J

    2012-01-01

    Nanocrystalline zirconia (ZrO2) film with thickness of 305 nm deposited on a silicon substrate was irradiated with 2 MeV Au ions to different fluences at different temperatures. The implanted ion profiles were measured by time-of-flight secondary ion mass spectrometry (ToF-SIMS) and simulated using the stopping and range of ions in matter (SRIM) code, respectively. The experimental results show that a large fraction of the incident Au ions penetrates through the ZrO2 film and are deposited into the Si substrate. At the interface of ZrO2 and Si, a sudden decrease of Au concentration is observed due to the much larger scattering cross section of Au in ZrO2 than in Si. The depth profile of the Au ions is measured in both the ZrO2 films and the Si substrates, and the results show that the Au distribution profiles do not exhibit a dependence on irradiation temperature. The local Au concentration increases proportionally with the irradiation fluence, suggesting that no thermal or irradiation-induced redistribution of the implanted Au ions. However, the Au concentration in the ZrO2 films, as determined by SIMS, is considerably lower than that predicted by the SRIM results, and the penetration depth from the SIMS measurements is much deeper than that from the SRIM predictions. These observations can be explained by an overestimation of the electronic stopping power, used in the SRIM program, for heavy incident ions in light targets. Overestimation of the heavy-ion electronic stopping power may lead to errors in local dose calculation and underestimation of the projected range of slow heavy ions in targets that contain light elements. A quick estimate based on a reduced target density may be used to compensate the overestimation of the electronic stopping power in the SRIM program to provide better ion profile prediction.

  8. Regenerative amplification of femtosecond pulses: Design and construction of a sub-100fs, {mu}J laser system

    SciTech Connect (OSTI)

    Schumacher, A.B. |

    1996-10-01

    Femtosecond lasers are a powerful tool for a wealth of applications in physics, chemistry and biology. In most cases, however, their use is fundamentally restricted to a rather narrow spectral range. This thesis deals with the construction and characterization of a femtosecond light source for spectroscopic applications which overcomes that restriction. It is demonstrated how the output of a continuously pumped Ti:sapphire femtosecond oscillator is amplified to the {mu}J level, while the pulse duration remains below 100fs. A combination of continuous pumping, acousto-optic switching and Ti:Al{sub 2}O{sub 3} as a gain medium allows amplification at high repetition rates. By focusing the high energy pulses into a sapphire crystal, a broad-band continuum can be generated, extended in wavelengths over several hundred nanometers. To accomplish amplification of three orders of magnitude while maintaining the pulse length, a regenerative multipass amplifier system was built. The thesis describes theoretical design, realization and characterization of the system. Theoretical calculations and preliminary measurements were carried out and allow a critical evaluation of the final performance.

  9. Track recognition in 4 [mu]s by a systolic trigger processor using a parallel Hough transform

    SciTech Connect (OSTI)

    Klefenz, F.; Noffz, K.H.; Conen, W.; Zoz, R.; Kugel, A. . Lehrstuhl fuer Informatik V); Maenner, R. . Lehrstuhl fuer Informatik V Univ. Heidelberg . Interdisziplinaeres Zentrum fuer Wissenschaftliches Rechnen)

    1993-08-01

    A parallel Hough transform processor has been developed that identifies circular particle tracks in a 2D projection of the OPAL jet chamber. The high-speed requirements imposed by the 8 bunch crossing mode of LEP could be fulfilled by computing the starting angle and the radius of curvature for each well defined track in less than 4 [mu]s. The system consists of a Hough transform processor that determines well defined tracks, and a Euler processor that counts their number by applying the Euler relation to the thresholded result of the Hough transform. A prototype of a systolic processor has been built that handles one sector of the jet chamber. It consists of 35 [times] 32 processing elements that were loaded into 21 programmable gate arrays (XILINX). This processor runs at a clock rate of 40 MHz. It has been tested offline with about 1,000 original OPAL events. No deviations from the off-line simulation have been found. A trigger efficiency of 93% has been obtained. The prototype together with the associated drift time measurement unit has been installed at the OPAL detector at LEP and 100k events have been sampled to evaluate the system under detector conditions.

  10. Enhanced efficiency of graphene-silicon Schottky junction solar cells by doping with Au nanoparticles

    SciTech Connect (OSTI)

    Liu, X.; Zhang, X. W. Yin, Z. G.; Meng, J. H.; Gao, H. L.; Zhang, L. Q.; Zhao, Y. J.; Wang, H. L.

    2014-11-03

    We have reported a method to enhance the performance of graphene-Si (Gr/Si) Schottky junction solar cells by introducing Au nanoparticles (NPs) onto the monolayer graphene and few-layer graphene. The electron transfer between Au NPs and graphene leads to the increased work function and enhanced electrical conductivity of graphene, resulting in a remarkable improvement of device efficiency. By optimizing the initial thickness of Au layers, the power conversion efficiency of Gr/Si solar cells can be increased by more than three times, with a maximum value of 7.34%. These results show a route for fabricating efficient and stable Gr/Si solar cells.

  11. High-frequency signal transmission through single-atom contacts of Au and

    Office of Scientific and Technical Information (OSTI)

    Pt (Journal Article) | SciTech Connect High-frequency signal transmission through single-atom contacts of Au and Pt Citation Details In-Document Search Title: High-frequency signal transmission through single-atom contacts of Au and Pt Signal transmission through atom-sized contacts of Au and Pt has been studied at room temperature for frequencies from 9 kHz to 1 GHz and for conductances (1-10)G{sub 0} (G≡2e{sup 2}/h is the quantum unit of conductance). We measured the frequency spectrum

  12. Growth and characterization of AuN films through the pulsed arc technique

    SciTech Connect (OSTI)

    Devia, A. Castillo, H.A.; Benavides, V.J.; Arango, Y.C.; Quintero, J.H.

    2008-02-15

    AuN films were produced through the PAPVD (Plasma Assisted Physics Vapor Deposition) method, using the pulsed arc technique in a mono-vaporizer noncommercial system, which consists of a chamber with two faced electrodes, and a power controlled system. In order to obtain the films, an Au Target with 99% purity and stainless steel 304 were used as target and substrate respectively. Nitrogen was injected in gaseous phase at 2.3 mbar pressure, and a discharge of 160 V was performed, supplied by the power controlled source. Au4f and N1s narrow spectra were analyzed using XPS (X-ray Photoelectron Spectroscopy)

  13. CoMuEx

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    To lead the Laboratory in its diverse activities in the areas concerning mix and turbulence under extreme conditions as related to stockpile stewardship, weapons, ICF, ...

  14. Efficient electrocatalytic conversion of CO.sub.2 to CO using ligand-protected Au.sub.25 clusters

    DOE Patents [OSTI]

    Kauffman, Douglas; Matranga, Christopher; Qian, Huifeng; Jin, Rongchao; Alfonso, Dominic R.

    2015-09-22

    An apparatus and method for CO.sub.2 reduction using an Au.sub.25 electrode. The Au.sub.25 electrode is comprised of ligand-protected Au.sub.25 having a structure comprising an icosahedral core of 13 atoms surrounded by a shell of six semi-ring structures bonded to the core of 13 atoms, where each semi-ring structure is typically --SR--Au--SR--Au--SR or --SeR--Au--SeR--Au--SeR. The 12 semi-ring gold atoms within the six semi-ring structures are stellated on 12 of the 20 faces of the icosahedron of the Au.sub.13 core, and organic ligand --SR or --SeR groups are bonded to the Au.sub.13 core with sulfur or selenium atoms. The Au.sub.25 electrode and a counter-electrode are in contact with an electrolyte comprising CO.sub.2 and H+, and a potential of at least -0.1 volts is applied from the Au.sub.25 electrode to the counter-electrode.

  15. CO Oxidation at the Interface of Au Nanoclusters and the Stepped-CeO2(111) Surface

    SciTech Connect (OSTI)

    Kim H. Y.; Henkelman, G.

    2013-01-14

    To reveal the richer chemistry of CO oxidation by CeO2 supported Au Nanoclusters NCs)/Nanoparticles, we design a Au12 supported on a stepped-CeO2 model (Au/CeO2-step) and study various kinds of CO oxidation mechanisms at the interface of the Au/CeO2-step: oxygen spillover from the CeO2 to the Au NCs;2 CO oxidation by the O2 bound to the Au-Ce3+ interface;3 and CO oxidation by the Mars-van Krevelen (M-vK) mechanism.4 DFT+U calculations show that lattice oxygen at the CeO2 step edge oxidizes CO bound to Au NCs by the M-vK mechanism. CO2 desorption determines the rate of CO oxidation and the vacancy formation energy (Evac) is a reactivity descriptor for CO oxidation. The maximum Evac that insures spontaneous CO2 production is higher for the Au/CeO2-step than the Au/CeO2-surface suggesting that the CeO2-step is a better supporting material than the CeO2-surface for CO oxidation by the Au/CeO2. Our results also suggest that for CO oxidation by Au NCs supported on nano- or meso-structured CeO2, which is the case of industrial catalysts, the M-vK mechanism accounts for a large portion of the total activity.

  16. Systematic study of azimuthal anisotropy in Cu + Cu and Au + Au collisions at √sNN = 62.4 and 200 GeV

    SciTech Connect (OSTI)

    Adare, A.

    2015-09-23

    We have studied the dependence of azimuthal anisotropy v2 for inclusive and identified charged hadrons in Au+Au and Cu+Cu collisions on collision energy, species, and centrality. The values of v2 as a function of transverse momentum pT and centrality in Au+Au collisions at √sNN=200 and 62.4 GeV are the same within uncertainties. However, in Cu+Cu collisions we observe a decrease in v2 values as the collision energy is reduced from 200 to 62.4 GeV. The decrease is larger in the more peripheral collisions. By examining both Au+Au and Cu+Cu collisions we find that v2 depends both on eccentricity and the number of participants, Npart. We observe that v2 divided by eccentricity (ε) monotonically increases with Npart and scales as N1/3part. Thus, the Cu+Cu data at 62.4 GeV falls below the other scaled v2 data. For identified hadrons, v2 divided by the number of constituent quarks nq is independent of hadron species as a function of transverse kinetic energy KET=mT–m between 0.1T/nq<1 GeV. Combining all of the above scaling and normalizations, we observe a near-universal scaling, with the exception of the Cu+Cu data at 62.4 GeV, of v2/(nq∙ε∙N1/3part) vs KET/nq for all measured particles.

  17. Systematic study of azimuthal anisotropy in Cu + Cu and Au + Au collisions at √sNN = 62.4 and 200 GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adare, A.

    2015-09-23

    We have studied the dependence of azimuthal anisotropy v2 for inclusive and identified charged hadrons in Au+Au and Cu+Cu collisions on collision energy, species, and centrality. The values of v2 as a function of transverse momentum pT and centrality in Au+Au collisions at √sNN=200 and 62.4 GeV are the same within uncertainties. However, in Cu+Cu collisions we observe a decrease in v2 values as the collision energy is reduced from 200 to 62.4 GeV. The decrease is larger in the more peripheral collisions. By examining both Au+Au and Cu+Cu collisions we find that v2 depends both on eccentricity and themore » number of participants, Npart. We observe that v2 divided by eccentricity (ε) monotonically increases with Npart and scales as N1/3part. Thus, the Cu+Cu data at 62.4 GeV falls below the other scaled v2 data. For identified hadrons, v2 divided by the number of constituent quarks nq is independent of hadron species as a function of transverse kinetic energy KET=mT–m between 0.1T/nq<1 GeV. Combining all of the above scaling and normalizations, we observe a near-universal scaling, with the exception of the Cu+Cu data at 62.4 GeV, of v2/(nq∙ε∙N1/3part) vs KET/nq for all measured particles.« less

  18. Supported Au-CuO Catalysts for Low Temperature CO Oxidation

    Broader source: Energy.gov [DOE]

    Catalytic properties of Au-CuOx/SiO2 are investigated in removing pollutants from simulated automotive exhaust to meet an increasing demand for high emissions control at low temperatures.

  19. Effect of growth temperature on ballistic electron transport through the Au/Si(001) interface

    SciTech Connect (OSTI)

    Eckes, M. W.; Friend, B. E.; Stollenwerk, A. J.

    2014-04-28

    Ballistic electron emission spectroscopy was used to investigate electron transport through Au/Si(001) Schottky diodes grown at 35?C and 22?C. Aside from a decreased Schottky height, this small increase in temperature introduced an energy dependent scattering component, which was absent in the samples grown at 22?C. These differences may be attributed to the increased amount of Au-Si intermixing at the interface. Despite the non-epitaxial nature of the growth technique, strong evidence was found in both sets of samples that indicated the presence of a forward-focused current subject to some degree of parallel momentum conservation at the interface. This evidence was present in all samples grown at 35?C, but was only observed in those samples grown at 22?C when the Au films were 10?nm or thicker. This sensitivity to growth temperature could account for discrepancies in previous studies on Au/Si(001)

  20. LAKESHORE AVON BR ANT-EDEN ALD EN-LANC ASTER AU BURN W SH ELDON

    U.S. Energy Information Administration (EIA) Indexed Site

    81 81 LAKESHORE AVON BR ANT-EDEN ALD EN-LANC ASTER AU BURN W SH ELDON CALEDONIA HURON C REEK LEIC EST ER COL DEN ASH FORD INDIAN FALLS LAWTONS SAR DINIA RPD-037 -2 ...

  1. Photoactivation experiment on {sup 197}Au and its implications for the dipole strength in heavy nuclei

    SciTech Connect (OSTI)

    Nair, C.; Erhard, M.; Junghans, A. R.; Bemmerer, D.; Beyer, R.; Klug, J.; Kosev, K.; Rusev, G.; Schilling, K. D.; Schwengner, R.; Wagner, A.; Grosse, E.

    2008-11-15

    The {sup 197}Au({gamma},n) reaction is used as an activation standard for photodisintegration studies on astrophysically relevant nuclei. At the bremsstrahlung facility of the superconducting electron accelerator ELBE (Electron Linear accelerator of high Brilliance and low Emittance) of Forschungszentrum Dresden-Rossendorf, photoactivation measurements on {sup 197}Au have been performed with bremsstrahlung endpoint energies from 8.0 to 15.5 MeV. The measured activation yield is compared with previous experiments as well as with calculations using Hauser-Feshbach statistical models. It is shown that the experimental data are best described by a two-Lorentzian parametrization with taking the axial deformation of {sup 197}Au into account. The experimental {sup 197}Au({gamma},n) reaction yield measured at ELBE via the photoactivation method is found to be consistent with previous experimental data using photon scattering or neutron detection methods.

  2. ARM Climate Modeling Best Estimate From Darwin, AU (ARMBE-ATM...

    Office of Scientific and Technical Information (OSTI)

    TWPC3) Title: ARM Climate Modeling Best Estimate From Darwin, AU (ARMBE-ATM TWPC3) The ARM CMBE-ATM Xie, McCoy, Klein et al. data file contains a best estimate of several ...

  3. ARM Climate Modeling Best Estimate From Darwin, AU (ARMBE-ATM...

    Office of Scientific and Technical Information (OSTI)

    TWPC2) Title: ARM Climate Modeling Best Estimate From Darwin, AU (ARMBE-ATM TWPC2) The ARM CMBE-ATM Xie, McCoy, Klein et al. data file contains a best estimate of several ...

  4. Gold-rich R3Au7Sn3: Establishing the interdependence between electronic features and physical properties

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Provino, Alessia; Steinberg, Simon; Smetana, Volodymyr; Kulkarni, Ruta; Dhar, Sudesh K.; Manfrinetti, Pietro; Mudring, Anja -Verena

    2015-05-18

    Two new polar intermetallic compounds Y3Au7Sn3 (I) and Gd3Au7Sn3 (II) have been synthesized and their structures have been determined by single crystal X-ray diffraction (P63/m; Z = 2, a = 8.148(1)/8.185(3), and c = 9.394(2)/9.415(3) for I/II, respectively). They can formally be assigned to the Cu10Sn3 type and consist of parallel slabs of Sn centered, edge-sharing trigonal Au6 antiprisms connected through R3 (R = Y, Gd) triangles. Additional Au atoms reside in the centres of trigonal Au6 prisms forming Au@Au6 clusters with Au–Au distances of 2.906–2.960 Å, while the R–R contacts in the R3 groups are considerably larger than themore »sums of their metallic radii. These exclusive structural arrangements provide alluring systems to study the synergism between strongly correlated systems, particularly, those in the structure of (II), and extensive polar intermetallic contacts, which has been inspected by measurements of the magnetic properties, heat capacities and electrical conductivities of both compounds. Gd3Au7Sn3 shows an antiferromagnetic ordering at 13 K, while Y3Au7Sn3 is a Pauli paramagnet and a downward curvature in its electrical resistivity at about 1.9 K points to a superconducting transition. DFT-based band structure calculations on R3Au7Sn3 (R = Y, Gd) account for the results of the conductivity measurements and different spin ordering models of (II) provide conclusive hints about its magnetic structure. As a result, chemical bonding analyses of both compounds indicate that the vast majority of bonding originates from the heteroatomic Au–Gd and Au–Sn interactions, while homoatomic Au–Au bonding is evident within the Au@Au6 clusters.« less

  5. Measurement of J/ψ Azimuthal Anisotropy in Au+Au Collisions at √sNN=200 GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alekseev, I.; Alford, J.; Anson, C. D.; Aparin, A.; Arkhipkin, D.; et al

    2013-08-02

    The measurement of J/ψ azimuthal anisotropy is presented as a function of transverse momentum for different centralities in Au+Au collisions at √sNN>/sub>=200 GeV. The measured J/ψ elliptic flow is consistent with zero within errors for transverse momentum between 2 and 10 GeV/c. Our measurement suggests that J/ψ particles with relatively large transverse momenta are not dominantly produced by coalescence from thermalized charm quarks, when comparing to model calculations.

  6. Plexciton Dynamics: Exciton-Plasmon Coupling in a J-Aggregate-Au Nanoshell

    Office of Scientific and Technical Information (OSTI)

    Complex Provides a Mechanism for Nonlinearity (Journal Article) | SciTech Connect Journal Article: Plexciton Dynamics: Exciton-Plasmon Coupling in a J-Aggregate-Au Nanoshell Complex Provides a Mechanism for Nonlinearity Citation Details In-Document Search Title: Plexciton Dynamics: Exciton-Plasmon Coupling in a J-Aggregate-Au Nanoshell Complex Provides a Mechanism for Nonlinearity Coherently coupled plasmons and excitons give rise to new optical excitations- plexcitons - due to the strong

  7. Laminin receptor specific therapeutic gold nanoparticles (198AuNP-EGCg)

    Office of Scientific and Technical Information (OSTI)

    show efficacy in treating prostate cancer (Journal Article) | SciTech Connect Journal Article: Laminin receptor specific therapeutic gold nanoparticles (198AuNP-EGCg) show efficacy in treating prostate cancer Citation Details In-Document Search Title: Laminin receptor specific therapeutic gold nanoparticles (198AuNP-EGCg) show efficacy in treating prostate cancer Systemic delivery of therapeutic agents to solid tumors is hindered by vascular and interstitial barriers. We hypothesized that

  8. Disassembly of hot nuclear matter formed in Au-induced reactions near the Fermi energy

    SciTech Connect (OSTI)

    Delis, D.N.

    1993-09-01

    Complex fragment emission has been studied in the 60 MeV/A {sup 197}Au + {sup 12}C, {sup 27}Al, {sup 51}V, {sup nat}Cu, and {sup 197}Au reactions. Velocity spectra, angular distributions and cross sections have been constructed for each target from the inclusive data. Coincidence data including 2-, 3-, 4-, and 5-fold events have also been examined. Furthermore neutron multiplicity distributions have been obtained for the above reactions by utilizing a novel neutron calorimetric approach.

  9. Fabrication of two-dimensional Au at FePt core-shell nanoparticle arrays by

    Office of Scientific and Technical Information (OSTI)

    photochemical metal deposition (Journal Article) | SciTech Connect SciTech Connect Search Results Journal Article: Fabrication of two-dimensional Au at FePt core-shell nanoparticle arrays by photochemical metal deposition Citation Details In-Document Search Title: Fabrication of two-dimensional Au at FePt core-shell nanoparticle arrays by photochemical metal deposition In this report, we experimentally demonstrate that single platinum nanoparticles exhibit the necessary catalytic activity

  10. Grain growth of nanocrystalline 3C-SiC under Au ion irradiation at elevated

    Office of Scientific and Technical Information (OSTI)

    temperatures (Journal Article) | SciTech Connect Grain growth of nanocrystalline 3C-SiC under Au ion irradiation at elevated temperatures Citation Details In-Document Search Title: Grain growth of nanocrystalline 3C-SiC under Au ion irradiation at elevated temperatures Nanocrystalline silicon carbide (SiC) represents an excellent model system for a fundamental study of interfacial (grain boundary) processes under nuclear radiation, which are critical to the understanding of the response of

  11. 328Post shot analysis of plasma conditions of Au Spheres illuminated by the

    Office of Scientific and Technical Information (OSTI)

    URLLE Omega laser, as measured via Thomson scattering (Conference) | SciTech Connect Conference: 328Post shot analysis of plasma conditions of Au Spheres illuminated by the URLLE Omega laser, as measured via Thomson scattering Citation Details In-Document Search Title: 328Post shot analysis of plasma conditions of Au Spheres illuminated by the URLLE Omega laser, as measured via Thomson scattering Authors: Rosen, M D ; Ross, J S ; Scott, H A ; Landen, N ; Dewald, E ; Froula, D ; May, M ;

  12. Electronic structure and vibrational entropies of fcc Au-Fe alloys

    SciTech Connect (OSTI)

    Munoz, Jorge A.; Lucas, Matthew; Mauger, L; Halevy, I; Horwath, J; Semiatin, S L; Xiao, Yuming; Stone, Matthew B; Abernathy, Douglas L; Fultz, B.

    2013-01-01

    Phonon density of states (DOS) curves were measured on alloys of face-centered-cubic (fcc) Au-Fe using nuclear resonant inelastic x-ray scattering (NRIXS) and inelastic neutron scattering (INS). The NRIXS and INS results were combined to obtain the total phonon DOS and the partial phonon DOS curves of Au and Fe atoms. The 57Fe partial phonon DOS of the dilute alloy Au0.97 57Fe0.03 shows a localized mode centered 4.3% above the cutoff energy of the phonons in pure Au. The Mannheim model for impurity modes accurately reproduced this partial phonon DOS using the fcc Au phonon DOS with a ratio of host-host to impurity-host force constants of 1.55. First-principles calculations validated the assumption of first-nearest-neighbor forces in the Mannheim model and gave a similar ratio of force constants. The high energy local mode broadens with increasing Fe composition, but this has a small effect on the composition dependence of the vibrational entropy. The main effect on the vibrational entropy of alloying comes from a stiffening of the Au partial phonon DOS with Fe concentration. This stiffening is attributed to two main effects: 1) an increase in electron density in the free-electron-like states, and 2) stronger sd-hybridization. These two effects are comparable in magnitude.

  13. Bond-bending isomerism of Au2I3-: Competition between covalent bonding and aurophilicity

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Li, Wan -Lu; Liu, Hong -Tao; Jian, Tian; Lopez, Gary V.; Piazza, Zachary A.; Huang, Dao -Ling; Chen, Teng -Teng; Su, Jing; Yang, Ping; Chen, Xin; et al

    2015-10-13

    We report a joint photoelectron spectroscopy and theoretical investigation of the gaseous Au2I3– cluster, which is found to exhibit two types of isomers due to competition between Au–I covalent bonding and Au–Au aurophilic interactions. The covalent bonding favors a bent IAuIAuI– structure with an obtuse Au–I–Au angle (100.7°), while aurophilic interactions pull the two Au atoms much closer, leading to an acutely bent structure (72.0°) with an Au–Au distance of 3.08 Å. The two isomers are separated by a small barrier and are nearly degenerate with the obtuse isomer being slightly more stable. At low temperature, only the obtuse isomermore » is observed; distinct experimental evidence is observed for the co-existence of a combination of isomers with both acute and obtuse bending angles at room temperature. As a result, the two bond-bending isomers of Au2I3– reveal a unique example of one molecule being able to oscillate between different structures as a result of two competing chemical forces.« less

  14. Stability of Surface and Subsurface Hydrogen on and in Au/Ni Near-Surface Alloys

    SciTech Connect (OSTI)

    Celik, Fuat E.; Mavrikakis, Manos

    2015-10-01

    Periodic, self-consistent DFT-GGA (PW91) calculations were used to study the interaction of hydrogen atoms with the (111) surfaces of substitutional near-surface alloys (NSAs) of Au and Ni with different surface layer compositions and different arrangements of Au atoms in the surface layer. The effect of hydrogen adsorption on the surface and in the first and second subsurface layers of the NSAs was studied. Increasing the Au content in the surface layer weakens hydrogen binding on the surface, but strengthens subsurface binding, suggesting that the distribution of surface and subsurface hydrogen will be different than that on pure Ni(111). While the metal composition of the surface layer has an effect on the binding energy of hydrogen on NSA surfaces, the local composition of the binding site has a stronger effect. For example, fcc hollow sites consisting of three Ni atoms bind H nearly as strongly as on Ni(111), and fcc sites consisting of three Au atoms bind H nearly as weakly as on Au(111). Sites with one or two Au atoms show intermediate binding energies. The preference of hydrogen for three-fold Ni hollow sites alters the relative stabilities of different surface metal atom arrangements, and may provide a driving force for adsorbate-induced surface rearrangement.

  15. Search for high-mass resonances decaying to e mu in p anti-p collisions at s**(1/2) = 1.96-TeV

    SciTech Connect (OSTI)

    Abulencia, A.; Acosta, D.; Adelman, Jahred A.; Affolder, T.; Akimoto, T.; Albrow, M.G.; Ambrose, D.; Amerio, S.; Amidei, D.; Anastassov, A.; Anikeev, K.; /Taiwan, Inst. Phys. /Argonne /Barcelona, IFAE /Baylor U. /INFN, Bologna /Bologna U. /Brandeis U. /UC, Davis /UCLA /UC, San Diego /UC, Santa Barbara

    2006-03-01

    The authors describe a general search for resonances decaying to a neutral e{mu} final state in p{bar p} collisions at a center-of-mass energy of 1.96 TeV. Using a data sample representing 344 pb{sup -1} of integrated luminosity recorded by the CDF II experiment, they compare Standard Model predictions with the number of observed events for invariant masses between 50 and 800 GeV/c{sup 2}. Finding no significant excess (5 events observed vs. 7.7 {+-} 0.8 expected for M{sub e{mu}} > 100 GeV/c{sup 2}), they set limits on sneutrino and Z{prime} masses as functions of lepton family number violating couplings.

  16. A 1 A laser driver in 0.35 {mu}m complementary metal oxide semiconductor technology for a pulsed time-of-flight laser rangefinder

    SciTech Connect (OSTI)

    Nissinen, Jan; Kostamovaara, Juha

    2009-10-15

    An integrated complementary metal oxide semiconductor (CMOS) current pulse generator is presented which achieves an ampere-scale peak current pulse with a rise time and pulse width of less than 1 and 2.5 ns (pulse width at half maximum), respectively. The generator is implemented in a 0.35 {mu}m CMOS process and consists of four parallel n-type metal oxide semiconductor transistors driven by a scaled buffer chain to achieve fast switching.

  17. Nucleon-gold collisions at 200A GeV using tagged d + Au interactions in the PHOBOS detector

    SciTech Connect (OSTI)

    Back, B. B.; Nouicer, R.; Baker, M. D.; Ballintijn, M.; Barton, D. S.; Becker, B.; Betts, R. R.; Bickley, A. A; Stienberg, P.; Ioradnova, A.; Pak, R.; Sukhanov, A.

    2015-09-23

    Forward calorimetry in the PHOBOS detector has been used to study charged hadron production in d+Au, p+Au, and n+Au collisions at √sNN =200GeV. The forward proton calorimeter detectors are described and a procedure for determining collision centrality with these detectors is detailed. The deposition of energy by deuteron spectator nucleons in the forward calorimeters is used to identify p+Au and n+Au collisions in the data. A weighted combination of the yield of p+Au and n+Au is constructed to build a reference for Au+Au collisions that better matches the isospin composition of the gold nucleus. The pT and centrality dependence of the yield of this improved reference system is found to match that of d+Au. The shape of the charged-particle transverse momentum distribution is observed to extrapolate smoothly from p+p¯ to central d+Au as a function of the charged-particle pseudorapidity density. The asymmetry of positively and negatively charged hadron production in p+Au is compared to that of n+Au. No significant asymmetry is observed at midrapidity. In conclusion, these studies augment recent results from experiments at the CERN Large Hadron Collider and BNL Relativistic Heavy Ion Collider facilities to give a more complete description of particle production in p+A and d+A collisions, essential for the understanding the medium produced in high-energy nucleus-nucleus collisions.

  18. Nucleon-gold collisions at 200A GeV using tagged d + Au interactions in the PHOBOS detector

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Back, B. B.; Nouicer, R.; Baker, M. D.; Ballintijn, M.; Barton, D. S.; Becker, B.; Betts, R. R.; Bickley, A. A; Stienberg, P.; Ioradnova, A.; et al

    2015-09-23

    Forward calorimetry in the PHOBOS detector has been used to study charged hadron production in d+Au, p+Au, and n+Au collisions at √sNN =200GeV. The forward proton calorimeter detectors are described and a procedure for determining collision centrality with these detectors is detailed. The deposition of energy by deuteron spectator nucleons in the forward calorimeters is used to identify p+Au and n+Au collisions in the data. A weighted combination of the yield of p+Au and n+Au is constructed to build a reference for Au+Au collisions that better matches the isospin composition of the gold nucleus. The pT and centrality dependence ofmore » the yield of this improved reference system is found to match that of d+Au. The shape of the charged-particle transverse momentum distribution is observed to extrapolate smoothly from p+p¯ to central d+Au as a function of the charged-particle pseudorapidity density. The asymmetry of positively and negatively charged hadron production in p+Au is compared to that of n+Au. No significant asymmetry is observed at midrapidity. In conclusion, these studies augment recent results from experiments at the CERN Large Hadron Collider and BNL Relativistic Heavy Ion Collider facilities to give a more complete description of particle production in p+A and d+A collisions, essential for the understanding the medium produced in high-energy nucleus-nucleus collisions.« less

  19. Energy dependence of Kπ, pπ and Kp fluctuations in Au+Au collisions from √sNN=7.7 to 200 GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adamczyk, L.

    2015-08-07

    A search for the quantum chromodynamics (QCD) critical point was performed by the STAR experiment at the Relativistic Heavy Ion Collider, using dynamical fluctuations of unlike particle pairs. Heavy ion collisions were studied over a large range of collision energies with homogeneous acceptance and excellent particle identification, covering a significant range in the QCD phase diagram where a critical point may be located. Dynamical Kπ, pπ, and Kp fluctuations as measured by the STAR experiment in central 0–5% Au+Au collisions from center-of-mass collision energies √sNN=7.7 to 200 GeV are presented. The observable νdyn was used to quantify the magnitude ofmore » the dynamical fluctuations in event-by-event measurements of the Kπ, pπ, and Kp pairs. The energy dependences of these fluctuations from central 0–5% Au+Au collisions all demonstrate a smooth evolution with collision energy.« less

  20. Measurement of Υ(1S + 2S +3S) production in p + p and Au + Au collisions at \\(\\sqrt{s_{\\mathrm{NN}}}=200\\) GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adare, A.; Afanasiev, S.; Aidala, C.; Ajitanand, N. N.; Akiba, Y.; Akimoto, R.; Al-Bataineh, H.; Al-Ta'ani, H.; Alexander, J.; Angerami, A.; et al

    2015-02-24

    Measurements of bottomonium production in heavy-ion and p+p collisions at the Relativistic Heavy Ion Collider (RHIC) are presented. The inclusive yield of the three Υ states, Υ(1S + 2S + 3S), was measured in the PHENIX experiment via electron-positron decay pairs at midrapidity for Au+Au and p+p collisions at \\(\\sqrt{s_{\\mathrm{NN}}}=200\\) GeV. The Υ(1S + 2S + 3S) → e⁺e⁻ differential cross section at midrapidity was found to be Beedσ/dy = 108 ± 38 (stat) ± 15 (syst) ± 11 (luminosity) pb in p+p collisions. The nuclear modification factor in the 30% most central Au+Au collisions indicates a suppression of themore »total Υ state yield relative to the extrapolation from p+p collision data. Thus, the suppression is consistent with measurements at higher energies by the CMS experiment at the Large Hadron Collider.« less

  1. Measurement of Υ(1S + 2S +3S) production in p + p and Au + Au collisions at \\(\\sqrt{s_{\\mathrm{NN}}}=200\\) GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adare, A.; Afanasiev, S.; Aidala, C.; Ajitanand, N. N.; Akiba, Y.; Akimoto, R.; Al-Bataineh, H.; Al-Ta'ani, H.; Alexander, J.; Angerami, A.; et al

    2015-02-24

    Measurements of bottomonium production in heavy-ion and p+p collisions at the Relativistic Heavy Ion Collider (RHIC) are presented. The inclusive yield of the three Υ states, Υ(1S + 2S + 3S), was measured in the PHENIX experiment via electron-positron decay pairs at midrapidity for Au+Au and p+p collisions at \\(\\sqrt{s_{\\mathrm{NN}}}=200\\) GeV. The Υ(1S + 2S + 3S) → e⁺e⁻ differential cross section at midrapidity was found to be Beedσ/dy = 108 ± 38 (stat) ± 15 (syst) ± 11 (luminosity) pb in p+p collisions. The nuclear modification factor in the 30% most central Au+Au collisions indicates a suppression of themore » total Υ state yield relative to the extrapolation from p+p collision data. Thus, the suppression is consistent with measurements at higher energies by the CMS experiment at the Large Hadron Collider.« less

  2. Measurement of Υ(1S + 2S +3S) production in p + p and Au + Au collisions at \\(\\sqrt{s_{\\mathrm{NN}}}=200\\) GeV

    SciTech Connect (OSTI)

    Adare, A.; Afanasiev, S.; Aidala, C.; Ajitanand, N. N.; Akiba, Y.; Akimoto, R.; Al-Bataineh, H.; Al-Ta'ani, H.; Alexander, J.; Angerami, A.; Aoki, K.; Apadula, N.; Aphecetche, L.; Aramaki, Y.; Asai, J.; Asano, H.; Aschenauer, E. C.; Atomssa, E. T.; Averbeck, R.; Awes, T. C.; Azmoun, B.; Babintsev, V.; Bai, M.; Baksay, G.; Baksay, L.; Baldisseri, A.; Bannier, B.; Barish, K. N.; Barnes, P. D.; Bassalleck, B.; Basye, A. T.; Bathe, S.; Batsouli, S.; Baublis, V.; Baumann, C.; Baumgart, S.; Bazilevsky, A.; Belikov, S.; Belmont, R.; Bennett, R.; Berdnikov, A.; Berdnikov, Y.; Bickley, A. A.; Bing, X.; Blau, D. S.; Boissevain, J. G.; Bok, J. S.; Borel, H.; Boyle, K.; Brooks, M. L.; Buesching, H.; Bumazhnov, V.; Bunce, G.; Butsyk, S.; Camacho, C. M.; Campbell, S.; Castera, P.; Chang, B. S.; Chang, W. C.; Charvet, J. -L.; Chen, C. -H.; Chernichenko, S.; Chi, C. Y.; Chiu, M.; Choi, I. J.; Choi, J. B.; Choi, S.; Choudhury, R. K.; Christiansen, P.; Chujo, T.; Chung, P.; Churyn, A.; Chvala, O.; Cianciolo, V.; Citron, Z.; Cole, B. A.; Connors, M.; Constantin, P.; Csanád, M.; Csörgő, T.; Dahms, T.; Dairaku, S.; Das, K.; Datta, A.; Daugherity, M. S.; David, G.; Denisov, A.; d'Enterria, D.; Deshpande, A.; Desmond, E. J.; Dharmawardane, K. V.; Dietzsch, O.; Ding, L.; Dion, A.; Donadelli, M.; Drapier, O.; Drees, A.; Drees, K. A.; Dubey, A. K.; Durham, J. M.; Durum, A.; Dutta, D.; Dzhordzhadze, V.; D'Orazio, L.; Edwards, S.; Efremenko, Y. V.; Ellinghaus, F.; Engelmore, T.; Enokizono, A.; En'yo, H.; Esumi, S.; Eyser, K. O.; Fadem, B.; Fields, D. E.; Finger, M.; Finger, M.; Fleuret, F.; Fokin, S. L.; Fraenkel, Z.; Frantz, J. E.; Franz, A.; Frawley, A. D.; Fujiwara, K.; Fukao, Y.; Fusayasu, T.; Gainey, K.; Gal, C.; Garishvili, A.; Garishvili, I.; Glenn, A.; Gong, H.; Gong, X.; Gonin, M.; Gosset, J.; Goto, Y.; Granier de Cassagnac, R.; Grau, N.; Greene, S. V.; Grosse Perdekamp, M.; Gunji, T.; Guo, L.; Gustafsson, H. -Å.; Hachiya, T.; Hadj Henni, A.; Haggerty, J. S.; Hahn, K. I.; Hamagaki, H.; Han, R.; Hanks, J.; Hartouni, E. P.; Haruna, K.; Hashimoto, K.; Haslum, E.; Hayano, R.; He, X.; Heffner, M.; Hemmick, T. K.; Hester, T.; Hill, J. C.; Hohlmann, M.; Hollis, R. S.; Holzmann, W.; Homma, K.; Hong, B.; Horaguchi, T.; Hori, Y.; Hornback, D.; Huang, S.; Ichihara, T.; Ichimiya, R.; Iinuma, H.; Ikeda, Y.; Imai, K.; Imrek, J.; Inaba, M.; Iordanova, A.; Isenhower, D.; Ishihara, M.; Isobe, T.; Issah, M.; Isupov, A.; Ivanischev, D.; Ivanishchev, D.; Jacak, B. V.; Javani, M.; Jia, J.; Jiang, X.; Jin, J.; Johnson, B. M.; Joo, K. S.; Jouan, D.; Jumper, D. S.; Kajihara, F.; Kametani, S.; Kamihara, N.; Kamin, J.; Kaneti, S.; Kang, B. H.; Kang, J. H.; Kang, J. S.; Kapustinsky, J.; Karatsu, K.; Kasai, M.; Kawall, D.; Kazantsev, A. V.; Kempel, T.; Khanzadeev, A.; Kijima, K. M.; Kikuchi, J.; Kim, B. I.; Kim, C.; Kim, D. H.; Kim, D. J.; Kim, E.; Kim, E. -J.; Kim, H. J.; Kim, K. -B.; Kim, S. H.; Kim, Y. -J.; Kim, Y. K.; Kinney, E.; Kiriluk, K.; Kiss, Á.; Kistenev, E.; Klatsky, J.; Klay, J.; Klein-Boesing, C.; Kleinjan, D.; Kline, P.; Kochenda, L.; Komatsu, Y.; Komkov, B.; Konno, M.; Koster, J.; Kotchetkov, D.; Kotov, D.; Kozlov, A.; Král, A.; Kravitz, A.; Krizek, F.; Kunde, G. J.; Kurita, K.; Kurosawa, M.; Kweon, M. J.; Kwon, Y.; Kyle, G. S.; Lacey, R.; Lai, Y. S.; Lajoie, J. G.; Layton, D.; Lebedev, A.; Lee, B.; Lee, D. M.; Lee, J.; Lee, K. B.; Lee, K. S.; Lee, S. H.; Lee, S. R.; Lee, T.; Leitch, M. J.; Leite, M. A. L.; Leitgab, M.; Lenzi, B.; Lewis, B.; Li, X.; Liebing, P.; Lim, S. H.; Linden Levy, L. A.; Liška, T.; Litvinenko, A.; Liu, H.; Liu, M. X.; Love, B.; Lynch, D.; Maguire, C. F.; Makdisi, Y. I.; Makek, M.; Malakhov, A.; Malik, M. D.; Manion, A.; Manko, V. I.; Mannel, E.; Mao, Y.; Mašek, L.; Masui, H.; Masumoto, S.; Matathias, F.; McCumber, M.; McGaughey, P. L.; McGlinchey, D.; McKinney, C.; Means, N.; Mendoza, M.; Meredith, B.; Miake, Y.; Mibe, T.; Mignerey, A. C.; Mikeš, P.; Miki, K.; Milov, A.; Mishra, D. K.; Mishra, M.; Mitchell, J. T.; Miyachi, Y.; Miyasaka, S.; Mohanty, A. K.; Moon, H. J.; Morino, Y.; Morreale, A.; Morrison, D. P.; Motschwiller, S.; Moukhanova, T. V.; Mukhopadhyay, D.; Murakami, T.; Murata, J.; Nagae, T.; Nagamiya, S.; Nagle, J. L.; Naglis, M.; Nagy, M. I.; Nakagawa, I.; Nakamiya, Y.; Nakamura, K. R.; Nakamura, T.; Nakano, K.; Nattrass, C.; Nederlof, A.; Newby, J.; Nguyen, M.; Nihashi, M.; Niida, T.; Nouicer, R.; Novitzky, N.; Nyanin, A. S.; O'Brien, E.; Oda, S. X.; Ogilvie, C. A.; Oka, M.; Okada, K.; Onuki, Y.; Oskarsson, A.; Ouchida, M.; Ozawa, K.; Pak, R.; Palounek, A. P. T.; Pantuev, V.; Papavassiliou, V.; Park, B. H.; Park, I. H.; Park, J.; Park, S. K.; Park, W. J.; Pate, S. F.; Patel, L.; Pei, H.; Peng, J. -C.; Pereira, H.; Peresedov, V.; Peressounko, D. Yu.; Petti, R.; Pinkenburg, C.; Pisani, R. P.; Proissl, M.; Purschke, M. L.; Purwar, A. K.; Qu, H.; Rak, J.; Rakotozafindrabe, A.; Ravinovich, I.; Read, K. F.; Rembeczki, S.; Reygers, K.; Reynolds, D.; Riabov, V.; Riabov, Y.; Richardson, E.; Riveli, N.; Roach, D.; Roche, G.; Rolnick, S. D.; Rosati, M.; Rosendahl, S. S. E.; Rosnet, P.; Rukoyatkin, P.; Ružička, P.; Rykov, V. L.; Sahlmueller, B.; Saito, N.; Sakaguchi, T.; Sakai, S.; Sakashita, K.; Samsonov, V.; Sano, M.; Sarsour, M.; Sato, T.; Sawada, S.; Sedgwick, K.; Seele, J.; Seidl, R.; Semenov, A. Yu.; Semenov, V.; Sen, A.; Seto, R.; Sharma, D.; Shein, I.; Shibata, T. -A.; Shigaki, K.; Shimomura, M.; Shoji, K.; Shukla, P.; Sickles, A.; Silva, C. L.; Silvermyr, D.; Silvestre, C.; Sim, K. S.; Singh, B. K.; Singh, C. P.; Singh, V.; Slunečka, M.; Soldatov, A.; Soltz, R. A.; Sondheim, W. E.; Sorensen, S. P.; Soumya, M.; Sourikova, I. V.; Staley, F.; Stankus, P. W.; Stenlund, E.; Stepanov, M.; Ster, A.; Stoll, S. P.; Sugitate, T.; Suire, C.; Sukhanov, A.; Sun, J.; Sziklai, J.; Takagui, E. M.; Takahara, A.; Taketani, A.; Tanabe, R.; Tanaka, Y.; Taneja, S.; Tanida, K.; Tannenbaum, M. J.; Tarafdar, S.; Taranenko, A.; Tarján, P.; Tennant, E.; Themann, H.; Thomas, T. L.; Todoroki, T.; Togawa, M.; Toia, A.; Tomášek, L.; Tomášek, M.; Tomita, Y.; Torii, H.; Towell, R. S.; Tram, V-N.; Tserruya, I.; Tsuchimoto, Y.; Tsuji, T.; Vale, C.; Valle, H.; van Hecke, H. W.; Vargyas, M.; Vazquez-Zambrano, E.; Veicht, A.; Velkovska, J.; Vértesi, R.; Vinogradov, A. A.; Virius, M.; Vossen, A.; Vrba, V.; Vznuzdaev, E.; Wang, X. R.; Watanabe, D.; Watanabe, K.; Watanabe, Y.; Watanabe, Y. S.; Wei, F.; Wei, R.; Wessels, J.; Whitaker, S.; White, S. N.; Winter, D.; Wolin, S.; Woody, C. L.; Wysocki, M.; Xie, W.; Yamaguchi, Y. L.; Yamaura, K.; Yang, R.; Yanovich, A.; Ying, J.; Yokkaichi, S.; You, Z.; Young, G. R.; Younus, I.; Yushmanov, I. E.; Zajc, W. A.; Zaudtke, O.; Zelenski, A.; Zhang, C.; Zhou, S.; Zolin, L.

    2015-02-24

    Measurements of bottomonium production in heavy-ion and p+p collisions at the Relativistic Heavy Ion Collider (RHIC) are presented. The inclusive yield of the three Υ states, Υ(1S + 2S + 3S), was measured in the PHENIX experiment via electron-positron decay pairs at midrapidity for Au+Au and p+p collisions at \\(\\sqrt{s_{\\mathrm{NN}}}=200\\) GeV. The Υ(1S + 2S + 3S) → e⁺e⁻ differential cross section at midrapidity was found to be Beedσ/dy = 108 ± 38 (stat) ± 15 (syst) ± 11 (luminosity) pb in p+p collisions. The nuclear modification factor in the 30% most central Au+Au collisions indicates a suppression of the total Υ state yield relative to the extrapolation from p+p collision data. Thus, the suppression is consistent with measurements at higher energies by the CMS experiment at the Large Hadron Collider.

  3. Energy dependence of Kπ, pπ and Kp fluctuations in Au+Au collisions from √sNN=7.7 to 200 GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adamczyk, L.

    2015-08-07

    A search for the quantum chromodynamics (QCD) critical point was performed by the STAR experiment at the Relativistic Heavy Ion Collider, using dynamical fluctuations of unlike particle pairs. Heavy ion collisions were studied over a large range of collision energies with homogeneous acceptance and excellent particle identification, covering a significant range in the QCD phase diagram where a critical point may be located. Dynamical Kπ, pπ, and Kp fluctuations as measured by the STAR experiment in central 0–5% Au+Au collisions from center-of-mass collision energies √sNN=7.7 to 200 GeV are presented. The observable νdyn was used to quantify the magnitude ofmore »the dynamical fluctuations in event-by-event measurements of the Kπ, pπ, and Kp pairs. The energy dependences of these fluctuations from central 0–5% Au+Au collisions all demonstrate a smooth evolution with collision energy.« less

  4. Efficient H{sub 2} production over Au/graphene/TiO{sub 2} induced by surface plasmon resonance of Au and band-gap excitation of TiO{sub 2}

    SciTech Connect (OSTI)

    Liu, Yang; Yu, Hongtao; Wang, Hua; Chen, Shuo; Quan, Xie

    2014-11-15

    Highlights: Both surface plasmon resonance and band-gap excitation were used for H{sub 2} production. Au/Gr/TiO{sub 2} composite photocatalyst was synthesized. Au/Gr/TiO{sub 2} exhibited enhancement of light absorption and charge separation. H{sub 2} production rate of Au/Gr/TiO{sub 2} was about 2 times as high as that of Au/TiO{sub 2}. - Abstract: H{sub 2} production over Au/Gr/TiO{sub 2} composite photocatalyst induced by surface plasmon resonance of Au and band-gap excitation of TiO{sub 2} using graphene (Gr) as an electron acceptor has been investigated. Electron paramagnetic resonance study indicated that, in this composite, Gr collected electrons not only from Au with surface plasmon resonance but also from TiO{sub 2} with band-gap excitation. Surface photovoltage and UVvis absorption measurements revealed that compared with Au/TiO{sub 2}, Au/Gr/TiO{sub 2} displayed more effective photogenerated charge separation and higher optical absorption. Benefiting from these advantages, the H{sub 2} production rate of Au/Gr/TiO{sub 2} composite with Gr content of 1.0 wt% and Au content of 2.0 wt% was about 2 times as high as that of Au/TiO{sub 2}. This work represents an important step toward the efficient application of both surface plasmon resonance and band-gap excitation on the way to converting solar light into chemical energy.

  5. Initial eccentricity in deformed {sup 197}Au+{sup 197}Au and {sup 238}U+{sup 238}U collisions at {radical}(s{sub NN})=200 GeV at the BNL Relativistic Heavy Ion Collider

    SciTech Connect (OSTI)

    Filip, Peter; Lednicky, Richard; Masui, Hiroshi; Xu Nu

    2009-11-15

    Initial eccentricity and eccentricity fluctuations of the interaction volume created in relativistic collisions of deformed {sup 197}Au and {sup 238}U nuclei are studied using optical and Monte Carlo (MC) Glauber simulations. It is found that the nonsphericity noticeably influences the average eccentricity in central collisions, and eccentricity fluctuations are enhanced from deformation. Quantitative results are obtained for Au+Au and U+U collisions at energy {radical}(s{sub NN})=200 GeV.

  6. Super-Stable, Highly Monodisperse Plasmonic Nanocrystals with 500 Gold Atoms: Au~500(SR)~120

    SciTech Connect (OSTI)

    Kumara, Chanaka; Zuo, Xiaobing; Ilavsky, Dr. Jan; Chapman, Karena; Cullen, David A; Dass, Amala

    2014-01-01

    Determining the composition of plasmonic nanoparticles is challenging due to a deficiency in tools capable of accurately evaluating the number of atoms. Mass spectrometry plays a significant role in determining nanoparticle composition at the atomic level. Significant progress has been made in understanding ultra-small gold nanoparticles, like Au25(SR)18 and Au38(SR)24, with a Au core diameter of 0.97 and 1.3 nm, respectively. However, progress in small plasmonic nanoparticles (2 - 5 nm) is currently challenging, due in part to limitations in synthesizing monodisperse nanoparticles. Here, we report a plasmonic nanocrystal that is highly monodisperse, with an unprecedented variation of less than 20 gold atoms. The composition of the super-stable plasmonic nanocrystals at 115 kDa was determined to contain Au500 10SR120 3. The Au~500 system, named Faraduarate-500, is the largest size to be characterized using high resolution ESI mass spectrometry. Atomic pair distribution function (PDF) data shows that the local atomic structure is consistent with a face-centered cubic (fcc) or Marks decahedral arrangement. High resolution scanning transmission electron microscopy images show that the diameter is 2.4 0.1 nm. The radius of gyration measured by small angle X-ray scattering (SAXS), is 1.05 0.05 nm, and the size and the shape of SAXS molecular envelope are in agreement with TEM and PDF measurements.

  7. Spin correlations and electron transport in MnBi:Au films

    SciTech Connect (OSTI)

    Kharel, P.; Skomski, R.; Sellmyer, D. J.

    2011-04-01

    The structural, magnetic, and electron transport properties of Mn{sub 55-x}Au{sub x}Bi{sub 45} (x = 0, 4.5) thin films prepared by magnetron sputtering have been investigated. The magnetization of the MnBi films decreases and the coercivity increases due to Au doping. The temperature dependence of resistivity between 2 to 300 K shows that the films are metallic but the 4.5% Au-doped film shows a Kondo behavior with resistance minimum at 10.2 K. The magnetoresistance is anisotropic and the positive transverse magnetoresistance is significantly enhanced (16.3% at 70 kOe) by Au doping. We interpret these data in terms of a model in which Au atoms preferentially substitute for Mn atoms on the Mn lattice, and some Mn atoms are displaced to interstitial sites in the NiAs structure. These interstitial Mn atoms are coupled antiferromagnetically to the Mn atoms on the original Mn lattice leading to the large decrease in magnetization, Kondo effect, and the positive magnetoresistance.

  8. Mechanical and Electrical Performance of Thermally Stable Au-ZnO films

    SciTech Connect (OSTI)

    Schoeppner, Rachel L.; Goeke, Ronald S.; Moody, Neville R.; Bahr, David F.

    2015-03-28

    The mechanical properties, thermal stability, and electrical performance of AuZnO composite thin films are determined in this work. The co-deposition of ZnO with Au via physical vapor deposition leads to grain refinement over that of pure Au; the addition of 0.1 vol.% ZnO reduces the as-grown grain size by over 30%. The hardness of the as-grown films doubles with 2% ZnO, from 1.8 to 3.6 GPa as measured by nanoindentation. Films with ZnO additions greater than 0.5% show no significant grain growth after annealing at 350 C, while pure gold and smaller additions do exhibit grain growth and subsequent mechanical softening. Films with 1% and 2% ZnO show a decrease of approximately 50% in electrical resistivity and no change in hardness after annealing. A model accounting for both changes in the interface structure between dispersed ZnO particles and the Au matrix captures the changes in mechanical and electrical resistivity. Furthermore, the addition of 12% ZnO co-deposited with Au provides a method to create mechanically hard and thermally stable films with a resistivity less than 80 n?-m. Our results complement previous studies of other alloying systems, suggesting oxide dispersion strengthened (ODS) gold shows a desirable hardnessresistivity relationship that is relatively independent of the particular ODS chemistry.

  9. INTERSTELLAR PICK-UP IONS OBSERVED BETWEEN 11 AND 22 AU BY NEW HORIZONS

    SciTech Connect (OSTI)

    Randol, B. M.; McComas, D. J.; Schwadron, N. A.

    2013-05-10

    We report new observations by the Solar Wind Around Pluto instrument on the New Horizons spacecraft, which measures energy per charge (E/q) spectra of solar wind and interstellar pick-up ions (PUIs) between 11 AU and 22 AU from the Sun. The data provide an unprecedented look at PUIs as there have been very few measurements of PUIs beyond 10 AU. We analyzed the PUI part of the spectra by comparing them to the classic Vasyliunas and Siscoe PUI model. Our analysis indicates that PUIs are usually well-described by this distribution. We derive parameters relevant to PUI studies, such as the ionization rate normalized to 1 AU. Our result for the average ionization rate between 11 and 12 AU agrees with an independently derived average value found during the same time. Later, we find a general increase in the ionization rate, which is consistent with the increase in solar activity. We also calculate the PUI thermal pressure, which appears to be roughly consistent with previous results. Through fitting of the solar wind proton peaks in our spectra, we derive solar wind thermal pressures. Based on our analysis, we predict a ratio of PUI thermal pressure to solar wind thermal pressure just inside the termination shock to be between 100 and >1000.

  10. TUNING OF SIZE AND SHAPE OF AU-PT NANOCATALYST FOR DIRECT METHANOL FUEL CELLS

    SciTech Connect (OSTI)

    Murph, S.

    2011-04-20

    In this paper, we report the precise control of the size, shape and surface morphology of Au-Pt nanocatalysts (cubes, blocks, octahedrons and dogbones) synthesized via a seed-mediated approach. Gold 'seeds' of different aspect ratios (1 to 4.2), grown by a silver-assisted approach, were used as templates for high-yield production of novel Au-Pt nanocatalysts at a low temperature (40 C). Characterization by electron microscopy (SEM, TEM, HRTEM), energy dispersive X-ray analysis (EDX), UV-Vis spectroscopy, zeta-potential (surface charge), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and inductively coupled plasma mass spectrometry (ICP-MS) were used to better understand their physico-chemical properties, preferred reactivities and underlying nanoparticle growth mechanism. A rotating disk electrode was used to evaluate the Au-Pt nanocatalysts electrochemical performance in the oxygen reduction reaction (ORR) and the methanol oxidation reaction (MOR) of direct methanol fuel cells. The results indicate the Au-Pt dogbones are partially and in some cases completely unaffected by methanol poisoning during the evaluation of the ORR. The ORR performance of the octahedron particles in the absence of MeOH is superior to that of the Au-Pt dogbones and Pt-black, however its performance is affected by the presence of MeOH.

  11. Controlled growth and multi-photon luminescence of hexagonal arrays of Au nanoparticles on anodic aluminum oxide templates

    SciTech Connect (OSTI)

    Li Jianbo; Yu Ying; Peng Xiaoniu; Yang Zhongjian; Zhou Li; Zhou Zhangkai

    2012-06-15

    Au nanoparticles were deposited onto anodic aluminum oxide (AAO) templates by using a rotating sputtering technique. Interestingly, hexagonal arrays of Au nanoparticles were obtained at an appropriate rotating rate and deposition time. Strong three-photon luminescence was observed from the hexagonally arrayed Au nanoparticles, which is attributed to the strong enhancements of local electromagnetic fields at both excitation and emission wavelengths. Our findings provide a new method to prepare Au nanoparticle arrays with large field enhancements and could have prospective applications in plasmonic nanodevices, such as surface-enhanced Raman scattering substrates, and biosensors.

  12. Systematic study of charged-pion and kaon femtoscopy in Au+Au collisions at ?sNN = 200 GeV

    SciTech Connect (OSTI)

    Adare, A.

    2015-09-23

    We present a systematic study of charged pion and kaon interferometry in Au+Au collisions at ?sNN=200 GeV. The kaon mean source radii are found to be larger than pion radii in the outward and longitudinal directions for the same transverse mass; this difference increases for more central collisions. The azimuthal-angle dependence of the radii was measured with respect to the second-order event plane and similar oscillations of the source radii were found for pions and kaons. Hydrodynamic models qualitatively describe the similar oscillations of the mean source radii for pions and kaons, but they do not fully describe the transverse-mass dependence of the oscillations.

  13. Systematic study of charged-pion and kaon femtoscopy in Au+Au collisions at √sNN = 200 GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adare, A.

    2015-09-23

    We present a systematic study of charged pion and kaon interferometry in Au+Au collisions at √sNN=200 GeV. The kaon mean source radii are found to be larger than pion radii in the outward and longitudinal directions for the same transverse mass; this difference increases for more central collisions. The azimuthal-angle dependence of the radii was measured with respect to the second-order event plane and similar oscillations of the source radii were found for pions and kaons. Hydrodynamic models qualitatively describe the similar oscillations of the mean source radii for pions and kaons, but they do not fully describe the transverse-massmore » dependence of the oscillations.« less

  14. Systematic study of charged-pion and kaon femtoscopy in Au+Au collisions at √sNN = 200 GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adare, A.

    2015-09-23

    We present a systematic study of charged pion and kaon interferometry in Au+Au collisions at √sNN=200 GeV. The kaon mean source radii are found to be larger than pion radii in the outward and longitudinal directions for the same transverse mass; this difference increases for more central collisions. The azimuthal-angle dependence of the radii was measured with respect to the second-order event plane and similar oscillations of the source radii were found for pions and kaons. Hydrodynamic models qualitatively describe the similar oscillations of the mean source radii for pions and kaons, but they do not fully describe the transverse-massmore »dependence of the oscillations.« less

  15. Heavy-quark production and elliptic flow in Au+Au collisions at ?sNN=62.4 GeV

    SciTech Connect (OSTI)

    Adare, A.

    2015-04-28

    In this study, we present measurements of electrons and positrons from the semileptonic decays of heavy-flavor hadrons at midrapidity (|y|< 0.35) in Au+Au collisions at ?sNN = 62.4 GeV. The data were collected in 2010 by the PHENIX experiment that included the new hadron-blind detector. The invariant yield of electrons from heavy-flavor decays is measured as a function of transverse momentum in the range 1 < peT < 5 GeV/c. The invariant yield per binary collision is slightly enhanced above the p+p reference in Au+Au 0%20%, 20%40%, and 40%60% centralities at a comparable level. At this low beam energy this may be a result of the interplay between initial-state Cronin effects, final-state flow, and energy loss in medium. The v? of electrons from heavy-flavor decays is nonzero when averaged between 1.3 < peT < 2.5 GeV/c for 0%40% centrality collisions at ?sNN = 62.4 GeV. For 20%40% centrality collisions, the v? at ?sNN = 62.4 GeV is smaller than that for heavy-flavor decays at ?sNN = 200 GeV. The v? of the electrons from heavy-flavor decay at the lower beam energy is also smaller than v? for pions. Both results indicate that the heavy-quarks interact with the medium formed in these collisions, but they may not be at the same level of thermalization with the medium as observed at ?sNN = 200 GeV.

  16. Heavy-quark production and elliptic flow in Au+Au collisions at √sNN=62.4 GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adare, A.

    2015-04-28

    In this study, we present measurements of electrons and positrons from the semileptonic decays of heavy-flavor hadrons at midrapidity (|y|< 0.35) in Au+Au collisions at √sNN = 62.4 GeV. The data were collected in 2010 by the PHENIX experiment that included the new hadron-blind detector. The invariant yield of electrons from heavy-flavor decays is measured as a function of transverse momentum in the range 1 < peT < 5 GeV/c. The invariant yield per binary collision is slightly enhanced above the p+p reference in Au+Au 0%–20%, 20%–40%, and 40%–60% centralities at a comparable level. At this low beam energy thismore » may be a result of the interplay between initial-state Cronin effects, final-state flow, and energy loss in medium. The v₂ of electrons from heavy-flavor decays is nonzero when averaged between 1.3 < peT < 2.5 GeV/c for 0%–40% centrality collisions at √sNN = 62.4 GeV. For 20%–40% centrality collisions, the v₂ at √sNN = 62.4 GeV is smaller than that for heavy-flavor decays at √sNN = 200 GeV. The v₂ of the electrons from heavy-flavor decay at the lower beam energy is also smaller than v₂ for pions. Both results indicate that the heavy-quarks interact with the medium formed in these collisions, but they may not be at the same level of thermalization with the medium as observed at √sNN = 200 GeV.« less

  17. LAKESHORE AVON BR ANT-EDEN ALD EN-LANC ASTER AU BURN W SH ELDON

    U.S. Energy Information Administration (EIA) Indexed Site

    81 § ¨ ¦ 81 LAKESHORE AVON BR ANT-EDEN ALD EN-LANC ASTER AU BURN W SH ELDON CALEDONIA HURON C REEK LEIC EST ER COL DEN ASH FORD INDIAN FALLS LAWTONS SAR DINIA RPD-037 -2 GLENWOOD PU LASKI PAVILION CON CORD COL LINS N ELM A ORC HARD PARK-H AMBU RG DANLEY CORNERS ST ILLWAT ER CHAFF EE-ARCAD E FAYETT E-WATERLOO LAKEVIEW JAVA SEN EC A W ELLER Y AU RORA E ZOAR BU FFALO TIOGA SILVER LAKE AKR ON ROM E RAT HBON E ALM A BET HANY WYOMING ULYSSES BR ANCH W SAN DY CREEK COL LINS BLOOMFIELD E LEBANON

  18. High-frequency signal transmission through single-atom contacts of Au and Pt

    SciTech Connect (OSTI)

    Aoyama, Shodai; Kurokawa, Shu; Sakai, Akira

    2015-03-23

    Signal transmission through atom-sized contacts of Au and Pt has been studied at room temperature for frequencies from 9 kHz to 1 GHz and for conductances (1?10)G{sub 0} (G?2e{sup 2}/h is the quantum unit of conductance). We measured the frequency spectrum of S parameter S{sub 21}=|S{sub 21}|e{sup i?} and found ??0 up to 1?GHz for all contacts irrespective of their conductance. Our observations directly prove that the atom-sized contacts of Au and Pt, including their single-atom contacts, behave as a pure resistance in the RF regime.

  19. Photoconductive response of a single Au nanorod coupled to LaAlO{sub

    Office of Scientific and Technical Information (OSTI)

    3}/SrTiO{sub 3} nanowires (Journal Article) | SciTech Connect Photoconductive response of a single Au nanorod coupled to LaAlO{sub 3}/SrTiO{sub 3} nanowires Citation Details In-Document Search Title: Photoconductive response of a single Au nanorod coupled to LaAlO{sub 3}/SrTiO{sub 3} nanowires Terahertz (THz) spectroscopy is an important tool that provides resonant access to free carrier motion, molecular rotation, lattice vibrations, excitonic, spin, and other degrees of freedom. Current

  20. Gold-rich R3Au7Sn3: Establishing the interdependence between electronic

    Office of Scientific and Technical Information (OSTI)

    features and physical properties (Journal Article) | SciTech Connect Journal Article: Gold-rich R3Au7Sn3: Establishing the interdependence between electronic features and physical properties Citation Details In-Document Search Title: Gold-rich R3Au7Sn3: Establishing the interdependence between electronic features and physical properties × You are accessing a document from the Department of Energy's (DOE) SciTech Connect. This site is a product of DOE's Office of Scientific and Technical

  1. Au-Ag Alloy Static High Pressure EOS measurements: FY09 summary of results

    Office of Scientific and Technical Information (OSTI)

    (Technical Report) | SciTech Connect Technical Report: Au-Ag Alloy Static High Pressure EOS measurements: FY09 summary of results Citation Details In-Document Search Title: Au-Ag Alloy Static High Pressure EOS measurements: FY09 summary of results Static high-pressure measurements of the equation of state of a Gold-Silver alloy (23.5 wt-% Ag) at room temperature were performed up to a pressure of approximately 100 GPA (1 megabar). Measurements were made using an energy-dispersive x-ray

  2. Density Functional Study of Au-n110(n = 3-5) Clusters on Relaxed Graphite

    Office of Scientific and Technical Information (OSTI)

    Surfaces (Journal Article) | SciTech Connect Density Functional Study of Au-n110(n = 3-5) Clusters on Relaxed Graphite Surfaces Citation Details In-Document Search Title: Density Functional Study of Au-n110(n = 3-5) Clusters on Relaxed Graphite Surfaces No abstract prepared. Authors: Wang, Guan M. ; BelBruno, Joseph J. ; Kenny, Steven D. ; Smith, Roger Publication Date: 2005-02-10 OSTI Identifier: 15011649 DOE Contract Number: AC05-76RL01830 Resource Type: Journal Article Resource Relation:

  3. ARM Climate Modeling Best Estimate From Darwin, AU (ARMBE-ATM TWPC2)

    Office of Scientific and Technical Information (OSTI)

    (Dataset) | Data Explorer Darwin, AU (ARMBE-ATM TWPC2) Title: ARM Climate Modeling Best Estimate From Darwin, AU (ARMBE-ATM TWPC2) The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data. Authors: McCoy, Renata ; Xie, Shaocheng Publication Date: 2013-12-26 OSTI Identifier: 1039934 DOE Contract Number: DE-AC05-00OR22725 Resource Type: Dataset Data Type: Numeric Data Research Org:

  4. ARM Climate Modeling Best Estimate From Darwin, AU (ARMBE-ATM TWPC3)

    Office of Scientific and Technical Information (OSTI)

    (Dataset) | Data Explorer Darwin, AU (ARMBE-ATM TWPC3) Title: ARM Climate Modeling Best Estimate From Darwin, AU (ARMBE-ATM TWPC3) The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data. Authors: McCoy, Renata ; Xie, Shaocheng Publication Date: 2013-12-26 OSTI Identifier: 1039935 DOE Contract Number: DE-AC05-00OR22725 Resource Type: Dataset Data Type: Numeric Data Research Org:

  5. Protein Viability on Au Nanoparticles during an Electrospray and Electrostatic-Force-Directed Assembly Process

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Mao, Shun; Lu, Ganhua; Yu, Kehan; Chen, Junhong

    2010-01-01

    We study the protein viability on Au nanoparticles during an electrospray and electrostatic-force-directed assembly process, through which Au nanoparticle-antibody conjugates are assembled onto the surface of carbon nanotubes (CNTs) to fabricate carbon nanotube field-effect transistor (CNTFET) biosensors. Enzyme-linked immunosorbent assay (ELISA) and field-effect transistor (FET) measurements have been used to investigate the antibody activity after the nanoparticle assembly. Upon the introduction of matching antigens, the colored reaction from the ELISA and the change in the electrical characteristic of the CNTFET device confirm that the antibody activity is preserved during the assembly process.

  6. Photo-induced wettability of TiO{sub 2} film with Au buffer layer

    SciTech Connect (OSTI)

    Purkayastha, Debarun Dhar; Sangani, L. D. Varma; Krishna, M. Ghanashyam; Madhurima, V.

    2014-04-24

    The effect of thickness of Au buffer layer (15-25 nm) between TiO{sub 2} film and substrate on the wettability of TiO{sub 2} films is reported. TiO{sub 2} films grown on Au buffer layer have a higher contact angle of 96-;100 as compared to 47.6o for the film grown without buffer layer. The transition from hydrophobicity to hydrophilicity under UV irradiation occurs within 10 min. for the buffer layered films whereas it is almost 30 min. for the film grown without buffer layer. The enhanced photo induced hydrophilicity is shown to be surface energy driven.

  7. Experimental evidences of a large extrinsic spin Hall effect in AuW alloy

    SciTech Connect (OSTI)

    Laczkowski, P.; Rojas-Sánchez, J.-C.

    2014-04-07

    We report an experimental study of a gold-tungsten alloy (7 at. % W concentration in Au host) displaying remarkable properties for spintronics applications using both magneto-transport in lateral spin valve devices and spin-pumping with inverse spin Hall effect experiments. A very large spin Hall angle of about 10% is consistently found using both techniques with the reliable spin diffusion length of 2 nm estimated by the spin sink experiments in the lateral spin valves. With its chemical stability, high resistivity, and small induced damping, this AuW alloy may find applications in the nearest future.

  8. PdAgAu alloy with high resistance to corrosion by H{sub 2}S

    SciTech Connect (OSTI)

    Braun, Fernando; Miller, James B.; Gellman, Andrew J.; Tarditi, Ana M.; Fleutot, Benoit; Petro, Kondratyuk, Cornaglia, Laura M

    2012-12-01

    PdAgAu alloy films were prepared on porous stainless steel supports by sequential electroless deposition. Two specific compositions, Pd{sub 83}Ag{sub 2}Au{sub 15} and Pd{sub 74}Ag{sub 14}Au{sub 12}, were studied for their sulfur tolerance. The alloys and a reference Pd foil were exposed to 1000 H{sub 2}S/H{sub 2} at 623 K for periods of 3 and 30 hours. The microstructure, morphology and bulk composition of both nonexposed and H{sub 2}S-exposed samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). XRD and SEM analysis revealed time-dependent growth of a bulk Pd{sub 4}S phase on the Pd foil during H{sub 2}S exposure. In contrast, the PdAgAu ternary alloys displayed the same FCC structure before and after H{sub 2}S exposure. In agreement with the XRD and SEM results, sulfur was not detected in the bulk of either ternary alloy samples by EDS, even after 30 hours of H{sub 2}S exposure. X-ray photoelectron spectroscopy (XPS) depth profiles were acquired for both PdAgAu alloys after 3 and 30 hours of exposure to characterize sulfur contamination near their surfaces. Very low S 2p and S 2s XPS signals were observed at the top-surfaces of the PdAgAu alloys, and those signals disappeared before the etch depth reached ~ 10 nm, even for samples exposed to H{sub 2}S for 30 hours. The depth profile analyses also revealed silver and gold segregation to the surface of the alloys; preferential location of Au on the alloys surface may be related to their resistance to bulk sulfide formation. In preliminary tests, a PdAgAu alloy membrane displayed higher initial H{sub 2} permeability than a similarly prepared pure Pd sample and, consistent with resistance to bulk sulfide formation, lower permeability loss in H{sub 2}S than pure Pd.

  9. A 5 {mu}m IMAGE OF {beta} PICTORIS b AT A SUB-JUPITER PROJECTED SEPARATION: EVIDENCE FOR A MISALIGNMENT BETWEEN THE PLANET AND THE INNER, WARPED DISK

    SciTech Connect (OSTI)

    Currie, Thayne; Kuchner, Marc; Thalmann, Christian; Matsumura, Soko; Madhusudhan, Nikku; Burrows, Adam

    2011-08-01

    We present and analyze a new M' detection of the young exoplanet {beta} Pictoris b from 2008 VLT/NaCo data at a separation of {approx}4 AU and a high signal-to-noise rereduction of L' data taken in 2009 December. Based on our orbital analysis, the planet's orbit is viewed almost perfectly edge-on (i {approx} 89 deg) and has a Saturn-like semimajor axis of 9.50 AU{sup +3.93} {sup AU}{sub -1.7AU}. Intriguingly, the planet's orbit is aligned with the major axis of the outer disk ({Omega} {approx} 31 deg.) but is probably misaligned with the warp/inclined disk at 80 AU, often cited as a signpost for the planet's existence. Our results motivate new studies to clarify how {beta} Pic b sculpts debris disk structures and whether a second planet is required to explain the warp/inclined disk.

  10. An X-ray Absorption Fine Structure study of Au adsorbed onto the non-metabolizing cells of two soil bacterial species

    SciTech Connect (OSTI)

    Song, Zhen; Kenney, Janice P.L.; Fein, Jeremy B.; Bunker, Bruce A.

    2015-02-09

    Gram-positive and Gram-negative bacterial cells can remove Au from Au(III)-chloride solutions, and the extent of removal is strongly pH dependent. In order to determine the removal mechanisms, X-ray Absorption Fine Structure (XAFS) spectroscopy experiments were conducted on non-metabolizing biomass of Bacillus subtilis and Pseudomonas putida with fixed Au(III) concentrations over a range of bacterial concentrations and pH values. X-ray Absorption Near Edge Structure (XANES) and Extended X-ray Absorption Fine Structure (EXAFS) data on both bacterial species indicate that more than 90% of the Au atoms on the bacterial cell walls were reduced to Au(I). In contrast to what has been observed for Au(III) interaction with metabolizing bacterial cells, no Au(0) or Au-Au nearest neighbors were observed in our experimental systems. All of the removed Au was present as adsorbed bacterial surface complexes. For both species, the XAFS data suggest that although Au-chloride-hydroxide aqueous complexes dominate the speciation of Au in solution, Au on the bacterial cell wall is characterized predominantly by binding of Au atoms to sulfhydryl functional groups and amine and/or carboxyl functional groups, and the relative importance of the sulfhydryl groups increases with increasing pH and with decreasing Au loading. The XAFS data for both microorganism species suggest that adsorption is the first step in the formation of Au nanoparticles by bacteria, and the results enhance our ability to account for the behavior of Au in bacteria-bearing geologic systems.

  11. Low temperature plasma channels generated in microcavity trenches with widths of 20-150 {mu}m and aspect ratios as large as 10{sup 4}:1

    SciTech Connect (OSTI)

    Lu, M.; Park, S.-J.; Cunningham, B. T.; Eden, J. G. [Department of Electrical and Computer Engineering, University of Illinois, Urbana, Illinois 61801 (United States)

    2008-03-10

    Low temperature plasma channels with widths as small as 20 {mu}m, cross-sectional areas of 400-12 000 {mu}m{sup 2}, and aspect ratios (channel length to width) of up to 10{sup 4}:1 have been generated on a steady state basis within sealed microcavity trenches fabricated by replica molding. With lengths up to 1 m and volumes of 10{sup -5}-{approx}10{sup -2} cm{sup 3}, these channels are situated in a dielectric barrier structure having a transverse, buried electrode geometry and are sustained by power loadings as high as {approx}1.2 kW cm{sup -3}. Current densities of {approx}5-10 A cm{sup -2} and estimated electron densities of {approx}10{sup 11}-10{sup 13} cm{sup -3} are produced with a 20 kHz sinusoidal voltage of V{sub rms}=225-325 V, rendering these channels of interest as on-chip plasma reactors or nonlinear optical conversion media. With the transversely excited, photolithographically defined microcavity structures reported here, plasma channels of at least several meters in length, and having an arbitrary, folded geometric pattern, can be generated.

  12. Thermal stability of bimetallic Au/Fe nanoparticles in silica matrix

    SciTech Connect (OSTI)

    Pannu, Compesh Singh, Udai B. Hooda, Sonu Kabiraj, D. Avasthi, D. K.

    2014-04-24

    Thin silica film containing Au and Fe bimetallic nanoparticles were prepared by atom beam cosputtering. The samples were annealed at different temperatures from 400 to 800° C to study the thermal stability of bimetallic nanoparticles using X ray diffraction. It is observed that at 800° C strong structural rearrangement took place leading to thermal decomposition of bimetallic nanoparticles.

  13. Mechanical and Electrical Performance of Thermally Stable Au-ZnO films

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Schoeppner, Rachel L.; Goeke, Ronald S.; Moody, Neville R.; Bahr, David F.

    2015-03-28

    The mechanical properties, thermal stability, and electrical performance of Au–ZnO composite thin films are determined in this work. The co-deposition of ZnO with Au via physical vapor deposition leads to grain refinement over that of pure Au; the addition of 0.1 vol.% ZnO reduces the as-grown grain size by over 30%. The hardness of the as-grown films doubles with 2% ZnO, from 1.8 to 3.6 GPa as measured by nanoindentation. Films with ZnO additions greater than 0.5% show no significant grain growth after annealing at 350 °C, while pure gold and smaller additions do exhibit grain growth and subsequent mechanicalmore » softening. Films with 1% and 2% ZnO show a decrease of approximately 50% in electrical resistivity and no change in hardness after annealing. A model accounting for both changes in the interface structure between dispersed ZnO particles and the Au matrix captures the changes in mechanical and electrical resistivity. Furthermore, the addition of 1–2% ZnO co-deposited with Au provides a method to create mechanically hard and thermally stable films with a resistivity less than 80 nΩ-m. Our results complement previous studies of other alloying systems, suggesting oxide dispersion strengthened (ODS) gold shows a desirable hardness–resistivity relationship that is relatively independent of the particular ODS chemistry.« less

  14. Plasmon-enhanced reverse water gas shift reaction over oxide supported Au catalysts

    SciTech Connect (OSTI)

    Upadhye, AA; Ro, I; Zeng, X; Kim, HJ; Tejedor, I; Anderson, MA; Dumesic, JA; Huber, GW

    2015-01-01

    We show that localized surface plasmon resonance (LSPR) can enhance the catalytic activities of different oxide-supported Au catalysts for the reverse water gas shift (RWGS) reaction. Oxide-supported Au catalysts showed 30 to 1300% higher activity for RWGS under visible light compared to dark conditions. Au/TiO2 catalyst prepared by the deposition-precipitation (DP) method with 3.5 nm average Au particle size showed the highest activity for the RWGS reaction. Visible light is converted into chemical energy for this reaction with up to a 5% overall efficiency. A shift in the apparent activation energy (from 47 kJ mol(-1) in dark to 35 kJ mol(-1) in light) and apparent reaction order with respect to CO2 (from 0.5 in dark to 1.0 in light) occurs due to the LSPR. Our kinetic results indicate that the LSPR increases the rate of either the hydroxyl hydrogenation or carboxyl decomposition more than any other steps in the reaction network.

  15. Yields of photoneutron reactions on {sup 197}Au nuclei in the giant-dipole-resonance region

    SciTech Connect (OSTI)

    Belyshev, S. S.; Ermakov, A. N.; Ishkhanov, B. S.; Kuznetsov, A. A.; Kurilik, A. S.; Stopani, K. A.; Troschiev, S. Yu.

    2011-11-15

    Yields of photonuclear reactions on 197Au nuclei were measured in a beam of bremsstrahlung photons, the endpoint energy of the bremsstrahlung spectrum being 29.1 MeV. These measurements were performed by means of the gamma-activation procedure. The results obtained in this way were compared with the results of earlier experiments and theoretical calculations.

  16. Nuclear matter effects on J/? production in asymmetric Cu + Au collisions at \\(\\sqrt{s_{\\mathrm{NN}}} = 200\\) GeV

    SciTech Connect (OSTI)

    Adare, A.; Aidala, C.; Ajitanand, N. N.; Akiba, Y.; Akimoto, R.; Alexander, J.; Alfred, M.; Aoki, K.; Apadula, N.; Aramaki, Y.; Asano, H.; Atomssa, E. T.; Awes, T. C.; Azmoun, B.; Babintsev, V.; Bai, M.; Bai, X.; Bandara, N. S.; Bannier, B.; Barish, K. N.; Bathe, S.; Baublis, V.; Baumann, C.; Baumgart, S.; Bazilevsky, A.; Beaumier, M.; Beckman, S.; Belmont, R.; Berdnikov, A.; Berdnikov, Y.; Bing, X.; Black, D.; Blau, D. S.; Bok, J. S.; Boyle, K.; Brooks, M. L.; Bryslawskyj, J.; Buesching, H.; Bumazhnov, V.; Butsyk, S.; Campbell, S.; Chen, C. -H.; Chi, C. Y.; Chiu, M.; Choi, I. J.; Choi, J. B.; Choi, S.; Christiansen, P.; Chujo, T.; Cianciolo, V.; Citron, Z.; Cole, B. A.; Cronin, N.; Crossette, N.; Csand, M.; Csrg?, T.; Datta, A.; Daugherity, M. S.; David, G.; DeBlasio, K.; Dehmelt, K.; Denisov, A.; Deshpande, A.; Desmond, E. J.; Ding, L.; Dion, A.; Do, J. H.; Drapier, O.; Drees, A.; Drees, K. A.; Durham, J. M.; Durum, A.; D'Orazio, L.; Engelmore, T.; Enokizono, A.; En'yo, H.; Esumi, S.; Eyser, K. O.; Fadem, B.; Feege, N.; Fields, D. E.; Finger, M.; Finger, M.; Fleuret, F.; Fokin, S. L.; Frantz, J. E.; Franz, A.; Frawley, A. D.; Fukao, Y.; Gainey, K.; Gal, C.; Gallus, P.; Garg, P.; Garishvili, A.; Garishvili, I.; Ge, H.; Giordano, F.; Glenn, A.; Gong, X.; Gonin, M.; Goto, Y.; Granier de Cassagnac, R.; Grau, N.; Greene, S. V.; Grosse Perdekamp, M.; Gu, Y.; Gunji, T.; Guragain, H.; Hachiya, T.; Haggerty, J. S.; Hahn, K. I.; Hamagaki, H.; Han, S. Y.; Hanks, J.; Hasegawa, S.; Hashimoto, K.; Hayano, R.; He, X.; Hemmick, T. K.; Hester, T.; Hill, J. C.; Hollis, R. S.; Homma, K.; Hong, B.; Hoshino, T.; Huang, J.; Huang, S.; Ichihara, T.; Ikeda, Y.; Imai, K.; Imazu, Y.; Inaba, M.; Iordanova, A.; Isenhower, D.; Isinhue, A.; Ivanishchev, D.; Jacak, B. V.; Jeon, S. J.; Jezghani, M.; Jia, J.; Jiang, X.; Johnson, B. M.; Joo, E.; Joo, K. S.; Jouan, D.; Jumper, D. S.; Kamin, J.; Kanda, S.; Kang, B. H.; Kang, J. H.; Kang, J. S.; Kapustinsky, J.; Kawall, D.; Kazantsev, A. V.; Key, J. A.; Khachatryan, V.; Khandai, P. K.; Khanzadeev, A.; Kihara, K.; Kijima, K. M.; Kim, C.; Kim, D. H.; Kim, D. J.; Kim, E. -J.; Kim, H. -J.; Kim, M.; Kim, Y. -J.; Kim, Y. K.; Kistenev, E.; Klatsky, J.; Kleinjan, D.; Kline, P.; Koblesky, T.; Kofarago, M.; Komkov, B.; Koster, J.; Kotchetkov, D.; Kotov, D.; Krizek, F.; Kurita, K.; Kurosawa, M.; Kwon, Y.; Lacey, R.; Lai, Y. S.; Lajoie, J. G.; Lebedev, A.; Lee, D. M.; Lee, G. H.; Lee, J.; Lee, K. B.; Lee, K. S.; Lee, S. H.; Leitch, M. J.; Leitgab, M.; Lewis, B.; Li, X.; Lim, S. H.; Liu, M. X.; Lynch, D.; Maguire, C. F.; Makdisi, Y. I.; Makek, M.; Manion, A.; Manko, V. I.; Mannel, E.; Maruyama, T.; McCumber, M.; McGaughey, P. L.; McGlinchey, D.; McKinney, C.; Meles, A.; Mendoza, M.; Meredith, B.; Miake, Y.; Mibe, T.; Mignerey, A. C.; Miller, A. J.; Milov, A.; Mishra, D. K.; Mitchell, J. T.; Miyasaka, S.; Mizuno, S.; Mohanty, A. K.; Montuenga, P.; Moon, T.; Morrison, D. P.; Moskowitz, M.; Moukhanova, T. V.; Murakami, T.; Murata, J.; Mwai, A.; Nagae, T.; Nagamiya, S.; Nagle, J. L.; Nagy, M. I.; Nakagawa, I.; Nakagomi, H.; Nakamiya, Y.; Nakamura, K. R.; Nakamura, T.; Nakano, K.; Nattrass, C.; Netrakanti, P. K.; Nihashi, M.; Niida, T.; Nouicer, R.; Novak, T.; Novitzky, N.; Nyanin, A. S.; O'Brien, E.; Ogilvie, C. A.; Oide, H.; Okada, K.; Orjuela Koop, J. D.; Oskarsson, A.; Ozaki, H.; Ozawa, K.; Pak, R.; Pantuev, V.; Papavassiliou, V.; Park, I. H.; Park, S.; Park, S. K.; Pate, S. F.; Patel, L.; Patel, M.; Peng, J. -C.; Perepelitsa, D. V.; Perera, G. D. N.; Peressounko, D. Yu.; Perry, J.; Petti, R.; Pinkenburg, C.; Pinson, R.; Pisani, R. P.; Purschke, M. L.; Qu, H.; Rak, J.; Ravinovich, I.; Read, K. F.; Reynolds, D.; Riabov, V.; Riabov, Y.; Richardson, E.; Riveli, N.; Roach, D.; Rolnick, S. D.; Rosati, M.; Rowan, Z.; Rubin, J. G.; Ryu, M. S.; Sahlmueller, B.; Saito, N.; Sakaguchi, T.; Sako, H.; Samsonov, V.; Sarsour, M.; Sato, S.; Sawada, S.; Schaefer, B.; Schmoll, B. K.; Sedgwick, K.; Seele, J.; Seidl, R.; Sekiguchi, Y.; Sen, A.; Seto, R.; Sett, P.; Sexton, A.; Sharma, D.; Shaver, A.; Shein, I.; Shibata, T. -A.; Shigaki, K.; Shimomura, M.; Shoji, K.; Shukla, P.; Sickles, A.; Silva, C. L.; Silvermyr, D.; Singh, B. K.; Singh, C. P.; Singh, V.; Skolnik, M.; Slune?ka, M.; Solano, S.; Soltz, R. A.; Sondheim, W. E.; Sorensen, S. P.; Soumya, M.; Sourikova, I. V.; Stankus, P. W.; Steinberg, P.; Stenlund, E.; Stepanov, M.; Ster, A.; Stoll, S. P.; Stone, M. R.; Sugitate, T.; Sukhanov, A.; Sumita, T.; Sun, J.; Sziklai, J.; Takahara, A.; Taketani, A.; Tanida, K.; Tannenbaum, M. J.; Tarafdar, S.; Taranenko, A.; Tennant, E.; Timilsina, A.; Todoroki, T.; Tomek, M.; Torii, H.; Towell, M.; Towell, R.; Towell, R. S.; Tserruya, I.; van Hecke, H. W.; Vargyas, M.; Vazquez-Zambrano, E.; Veicht, A.; Velkovska, J.; Vrtesi, R.; Virius, M.; Vrba, V.

    2014-12-18

    We report on J/? production from asymmetric Cu+Au heavy-ion collisions at \\(\\sqrt{s_{\\mathrm{NN}}} = 200\\) GeV at the Relativistic Heavy Ion Collider at both forward (Cu-going direction) and backward (Au-going direction) rapidities. The nuclear modification of J/? yields in Cu+Au collisions in the Au-going direction is found to be comparable to that in Au+Au collisions when plotted as a function of the number of participating nucleons. In the Cu-going direction, J/? production shows a stronger suppression. This difference is comparable in magnitude and has the same sign as the difference expected from shadowing effects due to stronger low-x gluon suppression in the larger Au nucleus. Thus, the relative suppression is opposite to that expected from hot nuclear matter dissociation, since a higher energy density is expected in the Au-going direction.

  17. Nuclear matter effects on J/ψ production in asymmetric Cu + Au collisions at \\(\\sqrt{s_{\\mathrm{NN}}} = 200\\) GeV

    SciTech Connect (OSTI)

    Adare, A.; Aidala, C.; Ajitanand, N. N.; Akiba, Y.; Akimoto, R.; Alexander, J.; Alfred, M.; Aoki, K.; Apadula, N.; Aramaki, Y.; Asano, H.; Atomssa, E. T.; Awes, T. C.; Azmoun, B.; Babintsev, V.; Bai, M.; Bai, X.; Bandara, N. S.; Bannier, B.; Barish, K. N.; Bathe, S.; Baublis, V.; Baumann, C.; Baumgart, S.; Bazilevsky, A.; Beaumier, M.; Beckman, S.; Belmont, R.; Berdnikov, A.; Berdnikov, Y.; Bing, X.; Black, D.; Blau, D. S.; Bok, J. S.; Boyle, K.; Brooks, M. L.; Bryslawskyj, J.; Buesching, H.; Bumazhnov, V.; Butsyk, S.; Campbell, S.; Chen, C. -H.; Chi, C. Y.; Chiu, M.; Choi, I. J.; Choi, J. B.; Choi, S.; Christiansen, P.; Chujo, T.; Cianciolo, V.; Citron, Z.; Cole, B. A.; Cronin, N.; Crossette, N.; Csanád, M.; Csörgő, T.; Datta, A.; Daugherity, M. S.; David, G.; DeBlasio, K.; Dehmelt, K.; Denisov, A.; Deshpande, A.; Desmond, E. J.; Ding, L.; Dion, A.; Do, J. H.; Drapier, O.; Drees, A.; Drees, K. A.; Durham, J. M.; Durum, A.; D'Orazio, L.; Engelmore, T.; Enokizono, A.; En'yo, H.; Esumi, S.; Eyser, K. O.; Fadem, B.; Feege, N.; Fields, D. E.; Finger, M.; Finger, M.; Fleuret, F.; Fokin, S. L.; Frantz, J. E.; Franz, A.; Frawley, A. D.; Fukao, Y.; Gainey, K.; Gal, C.; Gallus, P.; Garg, P.; Garishvili, A.; Garishvili, I.; Ge, H.; Giordano, F.; Glenn, A.; Gong, X.; Gonin, M.; Goto, Y.; Granier de Cassagnac, R.; Grau, N.; Greene, S. V.; Grosse Perdekamp, M.; Gu, Y.; Gunji, T.; Guragain, H.; Hachiya, T.; Haggerty, J. S.; Hahn, K. I.; Hamagaki, H.; Han, S. Y.; Hanks, J.; Hasegawa, S.; Hashimoto, K.; Hayano, R.; He, X.; Hemmick, T. K.; Hester, T.; Hill, J. C.; Hollis, R. S.; Homma, K.; Hong, B.; Hoshino, T.; Huang, J.; Huang, S.; Ichihara, T.; Ikeda, Y.; Imai, K.; Imazu, Y.; Inaba, M.; Iordanova, A.; Isenhower, D.; Isinhue, A.; Ivanishchev, D.; Jacak, B. V.; Jeon, S. J.; Jezghani, M.; Jia, J.; Jiang, X.; Johnson, B. M.; Joo, E.; Joo, K. S.; Jouan, D.; Jumper, D. S.; Kamin, J.; Kanda, S.; Kang, B. H.; Kang, J. H.; Kang, J. S.; Kapustinsky, J.; Kawall, D.; Kazantsev, A. V.; Key, J. A.; Khachatryan, V.; Khandai, P. K.; Khanzadeev, A.; Kihara, K.; Kijima, K. M.; Kim, C.; Kim, D. H.; Kim, D. J.; Kim, E. -J.; Kim, H. -J.; Kim, M.; Kim, Y. -J.; Kim, Y. K.; Kistenev, E.; Klatsky, J.; Kleinjan, D.; Kline, P.; Koblesky, T.; Kofarago, M.; Komkov, B.; Koster, J.; Kotchetkov, D.; Kotov, D.; Krizek, F.; Kurita, K.; Kurosawa, M.; Kwon, Y.; Lacey, R.; Lai, Y. S.; Lajoie, J. G.; Lebedev, A.; Lee, D. M.; Lee, G. H.; Lee, J.; Lee, K. B.; Lee, K. S.; Lee, S. H.; Leitch, M. J.; Leitgab, M.; Lewis, B.; Li, X.; Lim, S. H.; Liu, M. X.; Lynch, D.; Maguire, C. F.; Makdisi, Y. I.; Makek, M.; Manion, A.; Manko, V. I.; Mannel, E.; Maruyama, T.; McCumber, M.; McGaughey, P. L.; McGlinchey, D.; McKinney, C.; Meles, A.; Mendoza, M.; Meredith, B.; Miake, Y.; Mibe, T.; Mignerey, A. C.; Miller, A. J.; Milov, A.; Mishra, D. K.; Mitchell, J. T.; Miyasaka, S.; Mizuno, S.; Mohanty, A. K.; Montuenga, P.; Moon, T.; Morrison, D. P.; Moskowitz, M.; Moukhanova, T. V.; Murakami, T.; Murata, J.; Mwai, A.; Nagae, T.; Nagamiya, S.; Nagle, J. L.; Nagy, M. I.; Nakagawa, I.; Nakagomi, H.; Nakamiya, Y.; Nakamura, K. R.; Nakamura, T.; Nakano, K.; Nattrass, C.; Netrakanti, P. K.; Nihashi, M.; Niida, T.; Nouicer, R.; Novak, T.; Novitzky, N.; Nyanin, A. S.; O'Brien, E.; Ogilvie, C. A.; Oide, H.; Okada, K.; Orjuela Koop, J. D.; Oskarsson, A.; Ozaki, H.; Ozawa, K.; Pak, R.; Pantuev, V.; Papavassiliou, V.; Park, I. H.; Park, S.; Park, S. K.; Pate, S. F.; Patel, L.; Patel, M.; Peng, J. -C.; Perepelitsa, D. V.; Perera, G. D. N.; Peressounko, D. Yu.; Perry, J.; Petti, R.; Pinkenburg, C.; Pinson, R.; Pisani, R. P.; Purschke, M. L.; Qu, H.; Rak, J.; Ravinovich, I.; Read, K. F.; Reynolds, D.; Riabov, V.; Riabov, Y.; Richardson, E.; Riveli, N.; Roach, D.; Rolnick, S. D.; Rosati, M.; Rowan, Z.; Rubin, J. G.; Ryu, M. S.; Sahlmueller, B.; Saito, N.; Sakaguchi, T.; Sako, H.; Samsonov, V.; Sarsour, M.; Sato, S.; Sawada, S.; Schaefer, B.; Schmoll, B. K.; Sedgwick, K.; Seele, J.; Seidl, R.; Sekiguchi, Y.; Sen, A.; Seto, R.; Sett, P.; Sexton, A.; Sharma, D.; Shaver, A.; Shein, I.; Shibata, T. -A.; Shigaki, K.; Shimomura, M.; Shoji, K.; Shukla, P.; Sickles, A.; Silva, C. L.; Silvermyr, D.; Singh, B. K.; Singh, C. P.; Singh, V.; Skolnik, M.; Slunečka, M.; Solano, S.; Soltz, R. A.; Sondheim, W. E.; Sorensen, S. P.; Soumya, M.; Sourikova, I. V.; Stankus, P. W.; Steinberg, P.; Stenlund, E.; Stepanov, M.; Ster, A.; Stoll, S. P.; Stone, M. R.; Sugitate, T.; Sukhanov, A.; Sumita, T.; Sun, J.; Sziklai, J.; Takahara, A.; Taketani, A.; Tanida, K.; Tannenbaum, M. J.; Tarafdar, S.; Taranenko, A.; Tennant, E.; Timilsina, A.; Todoroki, T.; Tomášek, M.; Torii, H.; Towell, M.; Towell, R.; Towell, R. S.; Tserruya, I.; van Hecke, H. W.; Vargyas, M.; Vazquez-Zambrano, E.; Veicht, A.; Velkovska, J.; Vértesi, R.; Virius, M.; Vrba, V.; Vznuzdaev, E.; Wang, X. R.; Watanabe, D.; Watanabe, K.; Watanabe, Y.; Watanabe, Y. S.; Wei, F.; Whitaker, S.; Wolin, S.; Woody, C. L.; Wysocki, M.; Xia, B.; Xue, L.; Yalcin, S.; Yamaguchi, Y. L.; Yanovich, A.; Yokkaichi, S.; Yoon, I.; You, Z.; Younus, I.; Yushmanov, I. E.; Zajc, W. A.; Zelenski, A.; Zhou, S.

    2014-12-18

    We report on J/ψ production from asymmetric Cu+Au heavy-ion collisions at \\(\\sqrt{s_{\\mathrm{NN}}} = 200\\) GeV at the Relativistic Heavy Ion Collider at both forward (Cu-going direction) and backward (Au-going direction) rapidities. The nuclear modification of J/ψ yields in Cu+Au collisions in the Au-going direction is found to be comparable to that in Au+Au collisions when plotted as a function of the number of participating nucleons. In the Cu-going direction, J/ψ production shows a stronger suppression. This difference is comparable in magnitude and has the same sign as the difference expected from shadowing effects due to stronger low-x gluon suppression in the larger Au nucleus. Thus, the relative suppression is opposite to that expected from hot nuclear matter dissociation, since a higher energy density is expected in the Au-going direction.

  18. WISE TF: A MID-INFRARED, 3.4 {mu}m EXTENSION OF THE TULLY-FISHER RELATION USING WISE PHOTOMETRY

    SciTech Connect (OSTI)

    Lagattuta, David J.; Mould, Jeremy R.; Staveley-Smith, Lister; Hong Tao; Springob, Christopher M.; Masters, Karen L.; Koribalski, Baerbel S.; Jones, D. Heath

    2013-07-10

    We present a mid-infrared Tully-Fisher (TF) relation using photometry from the 3.4 {mu}m W1 band of the Wide-field Infrared Survey Explorer (WISE) satellite. The WISE TF relation is formed from 568 galaxies taken from the all-sky 2MASS Tully-Fisher (2MTF) galaxy catalog, spanning a range of environments including field, group, and cluster galaxies. This constitutes the largest mid-infrared TF relation constructed to date. After applying a number of corrections to galaxy magnitudes and line widths, we measure a master TF relation given by M{sub corr} = -22.24 - 10.05[log (W{sub corr}) - 2.5], with an average dispersion of {sigma}{sub WISE} = 0.686 mag. There is some tension between WISE TF and a preliminary 3.6 {mu}m relation, which has a shallower slope and almost no intrinsic dispersion. However, our results agree well with a more recent relation constructed from a large sample of cluster galaxies. We additionally compare WISE TF to the near-infrared 2MTF template relations, finding a good agreement between the TF parameters and total dispersions of WISE TF and the 2MTF K-band template. This fact, coupled with typical galaxy colors of (K - W1) {approx} 0, suggests that these two bands are tracing similar stellar populations, including the older, centrally-located stars in the galactic bulge which can (for galaxies with a prominent bulge) dominate the light profile.

  19. Centrality dependence of low-momentum direct-photon production in Au+Au collisions at sNN=200 GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adare, A.; Afanasiev, S.; Aidala, C.; Ajitanand, N. N.; Akiba, Y.; Akimoto, R.; Al-Bataineh, H.; Al-Ta'ani, H.; Alexander, J.; Angerami, A.; et al

    2015-06-05

    The PHENIX experiment at RHIC has measured the centrality dependence of the direct photon yield from Au+Au collisions at √sNN = 200 GeV down to pT = 0.4 GeV/c. Photons are detected via photon conversions to e⁺e⁻ pairs and an improved technique is applied that minimizes the systematic uncertainties that usually limit direct photon measurements, in particular at low pT . We find an excess of direct photons above the Ncoll-scaled yield measured in p+p collisions. This excess yield is well described by an exponential distribution with an inverse slope of about 240 MeV/c in the pT range from 0.6–2.0more » GeV/c. In this study, while the shape of the pT distribution is independent of centrality within the experimental uncertainties, the yield increases rapidly with increasing centrality, scaling approximately with N α part, where α = 1.38±0.03(stat)±0.07(syst).« less

  20. Charged-to-neutral correlation at forward rapidity in Au+Au collisions at sNN=200 GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alekseev, I.; Alford, J.; Anson, C. D.; Aparin, A.; Arkhipkin, D.; et al

    2015-03-20

    Event-by-event fluctuations of the ratio of inclusive charged to photon multiplicities at forward rapidity in Au+Au collision at √sNN=200 GeV have been studied. Dominant contribution to such fluctuations is expected to come from correlated production of charged and neutral pions. We search for evidences of dynamical fluctuations of different physical origins. Observables constructed out of moments of multiplicities are used as measures of fluctuations. Mixed events and model calculations are used as baselines. Results are compared to the dynamical net-charge fluctuations measured in the same acceptance. A non-zero statistically significant signal of dynamical fluctuations is observed in excess to themore » model prediction when charged particles and photons are measured in the same acceptance. Thus, we find that, unlike dynamical net-charge fluctuation, charge-neutral fluctuation is not dominated by correlation due to particle decay. Results are compared to the expectations based on the generic production mechanism of pions due to isospin symmetry, for which no significant (< 1%) deviation is observed.« less

  1. Charged-to-neutral correlation at forward rapidity in Au+Au collisions at sNN=200 GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alekseev, I.; Alford, J.; Anson, C. D.; Aparin, A.; Arkhipkin, D.; et al

    2015-03-20

    Event-by-event fluctuations of the ratio of inclusive charged to photon multiplicities at forward rapidity in Au+Au collision at √sNN=200 GeV have been studied. Dominant contribution to such fluctuations is expected to come from correlated production of charged and neutral pions. We search for evidences of dynamical fluctuations of different physical origins. Observables constructed out of moments of multiplicities are used as measures of fluctuations. Mixed events and model calculations are used as baselines. Results are compared to the dynamical net-charge fluctuations measured in the same acceptance. A non-zero statistically significant signal of dynamical fluctuations is observed in excess to themore »model prediction when charged particles and photons are measured in the same acceptance. Thus, we find that, unlike dynamical net-charge fluctuation, charge-neutral fluctuation is not dominated by correlation due to particle decay. Results are compared to the expectations based on the generic production mechanism of pions due to isospin symmetry, for which no significant (« less

  2. Centrality dependence of low-momentum direct-photon production in Au+Au collisions at sNN=200 GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adare, A.; Afanasiev, S.; Aidala, C.; Ajitanand, N. N.; Akiba, Y.; Akimoto, R.; Al-Bataineh, H.; Al-Ta'ani, H.; Alexander, J.; Angerami, A.; et al

    2015-06-05

    The PHENIX experiment at RHIC has measured the centrality dependence of the direct photon yield from Au+Au collisions at √sNN = 200 GeV down to pT = 0.4 GeV/c. Photons are detected via photon conversions to e⁺e⁻ pairs and an improved technique is applied that minimizes the systematic uncertainties that usually limit direct photon measurements, in particular at low pT . We find an excess of direct photons above the Ncoll-scaled yield measured in p+p collisions. This excess yield is well described by an exponential distribution with an inverse slope of about 240 MeV/c in the pT range from 0.6–2.0more »GeV/c. In this study, while the shape of the pT distribution is independent of centrality within the experimental uncertainties, the yield increases rapidly with increasing centrality, scaling approximately with N α part, where α = 1.38±0.03(stat)±0.07(syst).« less

  3. Centrality dependence of low-momentum direct-photon production in Au+Au collisions at ?sNN = 200 GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adare, A.

    2015-06-05

    The PHENIX experiment at RHIC has measured the centrality dependence of the direct photon yield from Au+Au collisions at ?sNN = 200 GeV down to pT = 0.4 GeV/c. Photons are detected via photon conversions to e?e? pairs and an improved technique is applied that minimizes the systematic uncertainties that usually limit direct photon measurements, in particular at low pT . We find an excess of direct photons above the Ncoll-scaled yield measured in p+p collisions. This excess yield is well described by an exponential distribution with an inverse slope of about 240 MeV/c in the pT range from 0.62.0moreGeV/c. While the shape of the pT distribution is independent of centrality within the experimental uncertainties, the yield increases rapidly with increasing centrality, scaling approximately with N ? part, where ? = 1.380.03(stat)0.07(syst).less

  4. Energy dependence of Kπ, pπ and Kp fluctuations in Au+Au collisions from √sNN=7.7 to 200 GeV

    SciTech Connect (OSTI)

    Adamczyk, L.

    2015-08-07

    A search for the quantum chromodynamics (QCD) critical point was performed by the STAR experiment at the Relativistic Heavy Ion Collider, using dynamical fluctuations of unlike particle pairs. Heavy ion collisions were studied over a large range of collision energies with homogeneous acceptance and excellent particle identification, covering a significant range in the QCD phase diagram where a critical point may be located. Dynamical Kπ, pπ, and Kp fluctuations as measured by the STAR experiment in central 0–5% Au+Au collisions from center-of-mass collision energies √sNN=7.7 to 200 GeV are presented. The observable νdyn was used to quantify the magnitude of the dynamical fluctuations in event-by-event measurements of the Kπ, pπ, and Kp pairs. The energy dependences of these fluctuations from central 0–5% Au+Au collisions all demonstrate a smooth evolution with collision energy.

  5. The adsorption and reaction of vinyl acetate on Au/Pd(100) alloy surfaces

    SciTech Connect (OSTI)

    Li, Zhenjun [Pacific Northwest National Laboratory (PNNL); Calaza, Florencia C [ORNL; Tysoe, Wilfred [University of Wisconsin, Milwaukee

    2012-01-01

    The surface chemistry of vinyl acetate monomer (VAM) is studied on Au/Pd(100) alloys as a function of alloy composition using temperature-programmed desorption and reflection adsorption infrared spectroscopy. VAM adsorbs weakly on isolated palladium sites on the alloy with a heat of adsorption of ~55 kJ/mol, with the plane of the VAM adsorbed close to parallel to the surface. The majority of the VAM adsorbed on isolated sites desorbs molecularly with only a small portion decomposing. At lower gold coverages (below ~0.5 ML of gold), where palladium palladium bridge sites are present, VAM binds to the surface in a distorted geometry via a rehybridized vinyl group. A larger proportion of this VAM decomposes and this reaction is initiated by C\\O bond scission in the VAM to form adsorbed acetate and vinyl species. The implication of this surface chemistry for VAM synthesis on Au/Pd(100) alloys is discussed.

  6. Surface Plasmon Excitation via Au Nanoparticles in CdSe Semiconductor

    SciTech Connect (OSTI)

    Pradhan, A. K.; Konda, R. B.; Mundle, R.; Mustafa, H.; Bamiduro, O.; Roy, U. N.; Cui, Y.; Burger, A.

    2008-10-23

    We present experimental evidence for the large Raman and photoluminescence enhancement in CdSe semiconductor films grown on Si and glass substrates due to excitation of surface plasmon resonances in proximate gold metal nanoparticles deposited on the surface of CdSe film. Heterojunction diodes containing n-CdSe on p-Si semiconductor were fabricated and the surface of the diodes was in situ coated with Au nanoparticles using the ultra-high vacuum pulsed-laser deposition technique. A significant enhancement of the photocurrent was obtained in CdSe/p-Si containing Au nanoparticles on the surface compared to CdSe/p-Si due to the enhanced photo-absorption within the semiconductor by the phenomenon of surface plasmon resonance. These observations suggest a variety of approaches for improving the performance of devices such as photodetectors, photovoltaic, and related devices, including biosensors.

  7. The (111) Surface of NaAu2. Structure, Composition, and Stability

    SciTech Connect (OSTI)

    Kwolek, Emma J.; Widmer, Roland; Gröning, Oliver; Deniz, Okan; Walen, Holly; Yuen, Chad D.; Huang, Wenyu; Schlagel, Deborah L.; Wallingford, Mark; Thiel, Patricia A.

    2014-12-17

    The (111) surface of single-crystal NaAu2 is a model for catalytically active, powdered NaAu2. We prepare and characterize this surface with a broad suite of techniques. Preparation in ultrahigh vacuum consists of the traditional approach of ion bombardment (to remove impurities) and thermal annealing (to restore surface order). Both of these steps cause loss of sodium (Na), and repeated treatments eventually trigger conversion of the surface and near-surface regions to crystalline gold. The bulk has a limited ability to repopulate the surface Na. Under conditions where Na depletion is minimized, electron diffraction patterns are consistent with the bulk-terminated structure, and scanning tunneling microscopy reveals mesa-like features with lateral dimensions of a few tens of nanometers. The tops of the mesas do not possess fine structure characteristic of a periodic lattice, suggesting that the surface layer is disordered under the conditions of these experiments.

  8. Self-organization of S adatoms on Au(111): ?3R30 rows at low coverage

    SciTech Connect (OSTI)

    Walen, Holly; Liu, Da -Jiang; Oh, Junepyo; Lim, Hyunseob; Evans, J. W.; Kim, Yousoo; Thiel, P. A.

    2015-07-06

    Using scanning tunneling microscopy, we observe an adlayer structure that is dominated by short rows of S atoms, on unreconstructed regions of a Au(111) surface. This structure forms upon adsorption of low S coverage (less than 0.1 monolayer) on a fully reconstructed cleansurface at 300 K, then cooling to 5 K for observation. The rows adopt one of three orientations that are rotated by 30 from the close-packed directions of the Au(111) substrate, and adjacent S atoms in the rows are separated by ?3 times the surface lattice constant, a. Monte Carlo simulations are performed on lattice-gas models, we derived using a limited cluster expansion based on density functional theory energetics. Furthermore, models which include long-range pairwise interactions (extending to 5a), plus selected trio interactions, successfully reproduce the linear rows of S atoms at reasonable temperatures.

  9. Plasmonic Based Sensing Using an Array of Au-Metal Oxide Thin Films

    SciTech Connect (OSTI)

    Joy, N.; Rogers, Phillip H.; Nandasiri, Manjula I.; Thevuthasan, Suntharampillai; Carpenter, Michael A.

    2012-12-04

    An optical plasmonic-based sensing array has been developed and tested for the selective and sensitive detection of H2, CO, and NO2 at a temperature of 500C in an oxygen-containing background. The three element sensing array used Au nanoparticles embedded in separate thin films of yttria stabilized zirconia (YSZ), CeO2, and TiO2. A peak in the absorbance spectrum due to a localized surface plasmon resonance (LSPR) on the Au nanoparticles was monitored for each film during gas exposures and showed a blue shift in the peak positions for the reducing gases, H2 and CO, and a red shift for the oxidizing gas NO2. A more in-depth look at the sensing response was performed using the multivariate methods of principal component analysis (PCA) analysis and linear discriminant analysis (LDA) on data from across the entire absorbance spectrum range. Qualitative results from both methods showed good separation between the three analytes for both the full array and the Au-TiO2 sample. Quantification of LDA cluster separation using the Mahalanobis distance showed better cluster separation for the array, but there were some instances with the lowest concentrations where the single Au-TiO2 film had better separation than the array. A second method to quantify cluster separation in LDA space was developed using multidimensional volume analysis of the individual cluster volume, overlapped cluster volume and empty volume between clusters. Compared to the individual sensing elements, the array showed less cluster overlap, smaller cluster volumes, and more space between clusters, all of which were expected for improved separability between the analytes.

  10. Radio observations reveal a smooth circumstellar environment around the extraordinary type Ib supernova 2012au

    SciTech Connect (OSTI)

    Kamble, Atish; Soderberg, Alicia M.; Margutti, Raffaella; Milisavljevic, Dan; Chakraborti, Sayan; Dittmann, Jason; Drout, Maria; Sanders, Nathan; Chomiuk, Laura; Medvedev, Mikhail; Chevalier, Roger; Chugai, Nikolai; Fransson, Claes; Nakar, Ehud

    2014-12-10

    We present extensive radio and X-ray observations of SN 2012au, an energetic, radio-luminous supernova of Type Ib that exhibits multi-wavelength properties bridging subsets of hydrogen-poor superluminous supernovae, hypernovae, and normal core-collapse supernovae. The observations closely follow models of synchrotron emission from a shock-heated circumburst medium that has a wind density profile (??r {sup 2}). We infer a sub-relativistic velocity for the shock wave v ? 0.2 c and a radius of r ? 1.4 10{sup 16}cm at 25 days after the estimated date of explosion. For a wind velocity of 1000 km s{sup 1}, we determine the mass-loss rate of the progenitor to be M-dot =3.610{sup ?6} M{sub ?} yr{sup ?1}, consistent with the estimates from X-ray observations. We estimate the total internal energy of the radio-emitting material to be E ? 10{sup 47} erg, which is intermediate to SN 1998bw and SN 2002ap. The evolution of the radio light curve of SN 2012au is in agreement with its interaction with a smoothly distributed circumburst medium and the absence of stellar shells ejected from previous outbursts out to r ? 10{sup 17} cm from the supernova site. We conclude that the bright radio emission from SN 2012au was not dissimilar from other core-collapse supernovae despite its extraordinary optical properties, and that the evolution of the SN 2012au progenitor star was relatively quiet, marked with a steady mass loss, during the final years preceding explosion.

  11. In situ Formation of Highly Conducting Covalent Au-C Contacts for Single-Molecule Junctions

    SciTech Connect (OSTI)

    Cheng, Z.L.; Hybertsen, M.; Skouta, R.; Vazquez, H.; Widawsky, J.R.; Schneebeli, S.; Chen, W.; Breslow, R.; Venkataraman, L.

    2011-06-01

    Charge transport across metal-molecule interfaces has an important role in organic electronics. Typically, chemical link groups such as thiols or amines are used to bind organic molecules to metal electrodes in single-molecule circuits, with these groups controlling both the physical structure and the electronic coupling at the interface. Direct metal-carbon coupling has been shown through C60, benzene and {pi}-stacked benzene but ideally the carbon backbone of the molecule should be covalently bonded to the electrode without intervening link groups. Here, we demonstrate a method to create junctions with such contacts. Trimethyl tin (SnMe{sub 3})-terminated polymethylene chains are used to form single-molecule junctions with a break-junction technique. Gold atoms at the electrode displace the SnMe{sub 3} linkers, leading to the formation of direct Au-C bonded single-molecule junctions with a conductance that is {approx}100 times larger than analogous alkanes with most other terminations. The conductance of these Au-C bonded alkanes decreases exponentially with molecular length, with a decay constant of 0.97 per methylene, consistent with a non-resonant transport mechanism. Control experiments and ab initio calculations show that high conductances are achieved because a covalent Au-C sigma ({sigma}) bond is formed. This offers a new method for making reproducible and highly conducting metal-organic contacts.

  12. Visible light plasmonic heating of Au-ZnO for the catalytic reduction of CO2

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Wang, Congjun; Ranasingha, Oshadha; Natesakhawat, Sittichai; Ohodnicki, Paul R.; Andio, Mark; Lewis, James P.; Matranga, Christopher

    2013-01-01

    Plasmonic excitation of Au nanoparticles attached to the surface of ZnO catalysts using low power 532 nm laser illumination leads to significant heating of the catalyst and the conversion of CO2 and H2 reactants to CH4 and CO products. Temperature-calibrated Raman spectra of ZnO phonons show that intensity-dependent plasmonic excitation can controllably heat Au–ZnO from 30 to ~600 °C and simultaneously tune the CH4 : CO product ratio. The laser induced heating and resulting CH4 : CO product distribution agrees well with predictions from thermodynamic models and temperature-programmed reaction experiments indicating that the reaction is a thermally driven process resultingmore » from the plasmonic heating of the Au-ZnO. The apparent quantum yield for CO2 conversion under continuous wave (cw) 532 nm laser illumination is 0.030%. The Au-ZnO catalysts are robust and remain active after repeated laser exposure and cycling. The light intensity required to initiate CO2 reduction is low ( ~2.5 x 105 W m-2) and achievable with solar concentrators. Our results illustrate the viability of plasmonic heating approaches for CO2 utilization and other practical thermal catalytic applications.« less

  13. Growth of Single- and Bilayer ZnO on Au(111) and Interaction with Copper

    SciTech Connect (OSTI)

    Deng, Xingyi; Yao, Kun; Sun, Keju; Li, Wei-Xue; Lee, Junseok; Matranga, Christopher

    2013-05-30

    The stoichiometric single- and bi-layer ZnO(0001) have been prepared by reactive deposition of Zn on Au(111) and studied in detail with X-ray photoelectron spectroscopy, scanning tunneling microscopy, and density functional theory calculations. Both single- and bi-layer ZnO(0001) adopt a planar, graphite-like structure similar to freestanding ZnO(0001) due to the weak van der Waals interactions dominating their adhesion with the Au(111) substrate. At higher temperature, the single-layer ZnO(0001) converts gradually to bi-layer ZnO(0001) due to the twice stronger interaction between two ZnO layers than the interfacial adhesion of ZnO with Au substrate. It is found that Cu atoms on the surface of bi-layer ZnO(0001) are mobile with a diffusion barrier of 0.31 eV, and likely to agglomerate and form nanosized particles at low coverages; while Cu atoms tend to penetrate a single layer of ZnO(0001) with a barrier of 0.10 eV, resulting in a Cu free surface.

  14. LOCAL INTERSTELLAR HYDROGEN'S DISAPPEARANCE AT 1 AU: FOUR YEARS OF IBEX IN THE RISING SOLAR CYCLE

    SciTech Connect (OSTI)

    Saul, Lukas; Rodriguez, Diego; Scheer, Juergen; Wurz, Peter; Bzowski, Maciej; Kubiak, Marzena; Sokol, Justina; Fuselier, Stephen; McComas, Dave; Moebius, Eberhard

    2013-04-20

    NASA's Interstellar Boundary Explorer (IBEX) mission has recently opened a new window on the interstellar medium (ISM) by imaging neutral atoms. One ''bright'' feature in the sky is the interstellar wind flowing into the solar system. Composed of remnants of stellar explosions as well as primordial gas and plasma, the ISM is by no means uniform. The interaction of the local ISM with the solar wind shapes our heliospheric environment with hydrogen being the dominant component of the very local ISM. In this paper, we report on direct sampling of the neutral hydrogen of the local ISM over four years of IBEX observations. The hydrogen wind observed at 1 AU has decreased and nearly disappeared as the solar activity has increased over the last four years; the signal at 1 AU has dropped off in 2012 by a factor of {approx}8 to near background levels. The longitudinal offset has also increased with time presumably due to greater radiation pressure deflecting the interstellar wind. We present longitudinal and latitudinal arrival direction measurements of the bulk flow as measured over four years beginning at near solar minimum conditions. The H distribution we observe at 1 AU is expected to be different from that outside the heliopause due to ionization, photon pressure, gravity, and filtration by interactions with heliospheric plasma populations. These observations provide an important benchmark for modeling of the global heliospheric interaction. Based on these observations we suggest a further course of scientific action to observe neutral hydrogen over a full solar cycle with IBEX.

  15. Periodicity, Electronic Structures, and Bonding of Gold Tetrahalides [AuX4](-) (X = F, CI, Br, I, At, Uus)

    SciTech Connect (OSTI)

    Li, Wan-Lu; Li, Yong; Xu, Congqiao; Wang, Xue B.; Vorpagel, Erich R.; Li, Jun

    2015-12-07

    Systematic theoretical and experimental investigations have been performed to understand the periodicity and electronic structures of trivalent-gold halides using gold tetrahalides [AuX4]⁻ anions (X = F, Cl, Br, I, At, Uus). The [AuX4]⁻ (X = Cl, Br, I) anions were produced in gas phase and their negative-ion photoelectron spectra were obtained, which exhibited rich and well-resolved spectral peaks. We calculated the adiabatic as well as vertical electron detachment energies using density functional methods with scalar and spin-orbit coupling relativistic effects. The simulated photoelectron spectra based on these calculations are in good agreement with the experimental spectra. Our results show that the trivalent Au(III) oxidation state becomes progressively less stable while Au(I) is preferred when the halides become heavier along the Period Table. This trend reveals that the oxidation state of metals in complexes can be manipulated through ligand design

  16. Au impact on GaAs epitaxial growth on GaAs (111){sub B} substrates in molecular beam epitaxy

    SciTech Connect (OSTI)

    Liao, Zhi-Ming; Chen, Zhi-Gang; Xu, Hong-Yi; Guo, Ya-Nan; Sun, Wen; Zhang, Zhi; Yang, Lei; Lu, Zhen-Yu; Chen, Ping-Ping; Lu, Wei; Zou, Jin; Centre for Microscopy and Microanalysis, The University of Queensland, St. Lucia, Queensland 4072

    2013-02-11

    GaAs growth behaviour under the presence of Au nanoparticles on GaAs {l_brace}111{r_brace}{sub B} substrate is investigated using electron microscopy. It has been found that, during annealing, enhanced Ga surface diffusion towards Au nanoparticles leads to the GaAs epitaxial growth into {l_brace}113{r_brace}{sub B} faceted triangular pyramids under Au nanoparticles, governed by the thermodynamic growth, while during conventional GaAs growth, growth kinetics dominates, resulting in the flatted triangular pyramids at high temperature and the epitaxial nanowires growth at relatively low temperature. This study provides an insight of Au nanoparticle impact on GaAs growth, which is critical for understanding the formation mechanisms of semiconductor nanowires.

  17. Comparative study of the alloying effect on the initial oxidation of Cu-Au(100) and Cu-Pt(100)

    SciTech Connect (OSTI)

    Luo, Langli; Zhou, Guangwen; Kang, Yihong; Yang, Judith C.; Su, Dong; Stach, Eric A.

    2014-03-24

    Using in situ transmission electron microscopy, we show that the oxidation of the Cu-Au(100) results in the formation of Cu{sub 2}O islands that deeply embed into the Cu-Au substrate while the oxidation of the Cu-Pt(100) leads to the formation of Cu{sub 2}O islands that highly protrude above the Cu-Pt substrate. Their difference is attributed to the different mobilities of Pt and Au in the Cu base alloys for which the sluggish mobility of Pt in Cu results in trapped Pt atoms at the oxide/alloy interface while the faster mobility of Au in Cu leads to enhanced rehomogenization of the alloy composition.

  18. Catalytic epoxidation of propene with H2O-O2 reactants on Au/TiO2

    SciTech Connect (OSTI)

    Ojeda, Manuel; Iglesia, Enrique

    2008-11-05

    Au/TiO{sub 2} catalysts form hydroperoxy species from H{sub 2}O-O{sub 2} mixtures at near-ambient temperatures. These species can be used in the selective epoxidation of propene to propylene oxide.

  19. Exchange bias effect in Au-Fe3O4 dumbbell nanoparticles induced by the charge transfer from gold

    SciTech Connect (OSTI)

    Feygenson, Mikhail; Bauer, John C.; Gai, Zheng; Marques, Carlos; Aronson, Meigan C.; Teng, Xiaowei; Su, Dong; Stanic, Vesna; Urban, Volker S.; Beyer, Kevin A.; Dai, Sheng

    2015-08-10

    We have studied the origin of the exchange bias effect in the Au-Fe3O4 dumbbell nanoparticles in two samples with different sizes of the Au seed nanoparticles (4.1 and 2.7 nm) and same size of Fe3O4 nanoparticles (9.8 nm). The magnetization, small-angle neutron-scattering, synchrotron x-ray diffraction, and scanning transmission electron microscope measurements determined the antiferromagnetic FeO wustite phase within Fe3O4 nanoparticles, originating at the interface with the Au nanoparticles. The interface between antiferromagnetic FeO and ferrimagnetic Fe3O4 is giving rise to the exchange bias effect. The strength of the exchange bias fields depends on the interfacial area and lattice mismatch between both phases. We propose that the charge transfer from the Au nanoparticles is responsible for a partial reduction of the Fe3O4 into the FeO phase at the interface with Au nanoparticles. The Au-O bonds are formed, presumably across the interface to accommodate an excess of oxygen released during the reduction of magnetite

  20. Structural Changes in Self-Catalyzed Adsorption of Carbon Monoxide on 1,4-Phenylene Diisocyanide Modified Au(111)

    SciTech Connect (OSTI)

    Kestell, John; Boscoboinik, J. Anibal; Cheng, Lanxia; Garvey, Michael; Bennett, Dennis W.; Tysoe, Wilfred T.

    2015-07-23

    The self-accelerated adsorption of CO on 1,4-phenylene diisocyanide (PDI)-derived oligomers on Au(111) is explored by reflectionabsorption infrared spectroscopy and scanning tunneling microscopy. PDI incorporates gold adatoms from the Au(111) surface to form one-dimensional (AuPDI)n chains that can also connect between gold nanoparticles on mica to form a conductive pathway between them. CO adsorption occurs in two stages; it first adsorbs adjacent to the oligomers that move to optimize CO adsorption. Further CO exposure induces PDI decoordination to form AuPDI adatom complexes thereby causing the conductivity of a PDI-linked gold nanoparticle array on mica to decrease to act as a chemically drive molecular switch. This simple system enables the adsorption process to be explored in detail. DFT calculations reveal that both the (AuPDI)n oligomer chain and the AuPDI adatom complex are stabilized by coadsorbed CO. A kinetic foot-in-the-door model is proposed in which fluctuations in PDI coordination allow CO to diffuse into the gap between gold adatoms to prevent the PDI from reattaching, thereby allowing additional CO to adsorb, to provide kinetic model for allosteric CO adsorption on PDI-covered gold.

  1. Exchange bias effect in Au-Fe3O4 dumbbell nanoparticles induced by the charge transfer from gold

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Feygenson, Mikhail; Bauer, John C; Gai, Zheng; Marques, Carlos; Aronson, Meigan C.; Teng, Xiaowei; Su, Dong; Stanic, Vesna; Urban, Volker S; Kevin, Beyer; et al

    2015-01-01

    We have studied the origin of the exchange bias effect in the Au-Fe3O4 dumbbell nanoparticles in two samples with different sizes of the Au seed nanoparticles (4.1 and 2.7 nm) and same size of Fe3O4 nanoparticles (9.8 nm). The magnetization, small-angle neutron scattering, synchrotron x-ray diffraction and scanning transmission electron microscope measurements determined the antiferromagnetic FeO wüstite phase within Fe3O4 nanoparticles, originating at the interface with the Au nanoparticles. The interface between antiferromagnetic FeO and ferrimagnetic Fe3O4 is giving rise to the exchange bias effect. The strength of the exchange bias fields depends on the interfacial area and lattice mismatchmore » between both phases. We propose that the charge transfer from the Au nanoparticles is responsible for a partial reduction of the Fe3O4 into FeO phase at the interface with Au nanoparticles. The Au-O bonds are formed across the interface to accommodate an excess of oxygen released during the reduction of magnetite.« less

  2. THE INNER COMA OF COMET C/2012 S1 (ISON) AT 0.53 AU AND 0.35 AU FROM THE SUN

    SciTech Connect (OSTI)

    Bonev, Boncho P.; Villanueva, Geronimo L.; Paganini, Lucas; DiSanti, Michal A.; Gibb, Erika L.; Mumma, Michael J.

    2014-11-20

    Using long-slit spectroscopy at the NASA Infrared Telescope Facility, we extracted H{sub 2}O production rates and spatial profiles of gas rotational temperature and molecular column abundance in comet C/2012 S1 ISON, observed at heliocentric distances of 0.53 and 0.35 AU. These measurements uniquely probed the physical environment in the inner collisional coma of this comet during its first (and last) approach to the Sun since being emplaced in the Oort Cloud some 4.5 billion years ago. Our observations revealed a comet evolving on various timescales, both over hours and days. At 0.35 AU, ISON showed a considerable decrease in water production rate in less than 2 hr, likely declining from a major outburst. Our measured temperature spatial distributions reflect the competition between the processes that cause heating and cooling in the coma, and also provide insight about the prevalent mechanism(s) of releasing gas-phase H{sub 2}O. The observed temperatures suggest that the comet was likely ejecting icy material continuously, which sublimated in the coma and heated the ambient gas, augmenting fast H-atoms produced by H{sub 2}O photolysis. ISON adds to the very limited sample of comets for which spatial-spectral studies of water temperatures have been conducted. These studies are now feasible and can be extended to comets having a variety of gas production rates. Continued synergy of such observations with both space missions like Rosetta and with physical models is strongly encouraged in order to gain a deeper understanding of the processes in the inner collisional zone of the cometary coma.

  3. Structure, stability, and electronic property of carbon-doped gold clusters Au{sub n}C{sup ?} (n = 110): A density functional theory study

    SciTech Connect (OSTI)

    Yan, Li-Li; Liu, Yi-Rong; Huang, Teng; Jiang, Shuai; Wen, Hui; Gai, Yan-Bo; Zhang, Wei-Jun E-mail: wjzhang@aiofm.ac.cn; Huang, Wei E-mail: wjzhang@aiofm.ac.cn; School of Environmental Science and Optoelectronic Technology, University of Science and Technology of China, Hefei, Anhui 230026

    2013-12-28

    The equilibrium geometric structures, relative stabilities, and electronic properties of Au{sub n}C{sup ?} and Au{sub n+1}{sup ?} (n = 110) clusters are systematically investigated using density functional theory with hyper-generalized gradient approximation. The optimized geometries show that one Au atom capped on Au{sub n?1}C{sup ?} clusters is a dominant growth pattern for Au{sub n}C{sup ?} clusters. In contrast to Au{sub n+1}{sup ?} clusters, Au{sub n}C{sup ?} clusters are most stable in a quasi-planar or three-dimensional structure because C doping induces the local non-planarity while the rest of the structure continues to grow in a planar mode, resulting in an overall non-2D configuration. The relative stability calculations show that the impurity C atom can significantly enhance the thermodynamic stability of pure gold clusters. Moreover, the effect of C atom on the Au{sub n}{sup ?} host decreases with the increase of cluster size. The HOMO-LUMO gap curves show that the interaction of the C atom with Au{sub n}{sup ?} clusters improves the chemical stability of pure gold clusters, except for Au{sub 3}{sup ?} and Au{sub 4}{sup ?} clusters. In addition, a natural population analysis shows that the charges in corresponding Au{sub n}C{sup ?} clusters transfer from the Au{sub n}{sup ?} host to the C atom. Meanwhile, a natural electronic configuration analysis also shows that the charges mainly transfer between the 2s and 2p orbitals within the C atom.

  4. Characterization of one-dimensional molecular chains of 4,4'-biphenyl diisocyanide on Au(111) by scanning tunneling microscopy

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zhou, Jing; Li, Yan; Zahl, Percy; Sutter, Peter; Stacchiola, Dario J.; White, Michael G.

    2015-03-14

    The morphology and electronic structure of vapor deposited 4,4'-biphenyldiisocyanide (BPDI) on a Au(111) surface were investigated using variable-temperature scanning tunneling microscopy (STM). When deposited at room temperature, BPDI molecules form one-dimensional molecular chains similar to that recently observed for the structurally related 1,4-phenyl diisocyanide (PDI). Compared to PDI, the longer periodicity for the BPDI molecular chains is consistent with the addition of a second phenyl ring and supports a structural model in which the BPDI molecules lie parallel to the surface and interconnected by Au-adatoms. The molecular chains are mostly aligned along the [110] direction of the Au(111) substrate, butmore » exhibit frequent changes in angle that are consistent with directions between fcc and hcp three-fold hollow sites. Dispersion-corrected density functional theory calculations for one-dimensional chains of BPDI molecules bound end-to-end via their isocyanide groups to Au-adatoms reproduce the observed periodicity of the chains and show that this morphology is energetically favored over upright binding with one free –NC group. The spatially resolved conductance (dI/dV) map for BPDI on Au(111) exhibits a feature centered at -0.67 eV below the Fermi level which are delocalized along the chain with maxima at the Au-adatom and biphenyl positions. This occupied resonant feature is close to that previously observed for the PDI in both photoemission and conductance measurements and is attributed to an occupied interfacial state resulting from BPDI-Au interactions« less

  5. Hydrothermal synthesis of coral-like Au/ZnO catalyst and photocatalytic degradation of Orange II dye

    SciTech Connect (OSTI)

    Chen, P.K.; Lee, G.J.; Davies, S.H.; Masten, S.J.; Amutha, R.; Wu, J.J.

    2013-06-01

    Highlights: ? Coral-like Au/ZnO was successfully prepared using green synthetic method. ? Gold nanoparticles were deposited on the ZnO structure using NaBH{sub 4} and ?-D-glucose. ? Coral-like Au/ZnO exhibited superior photocatalytic activity to degrade Orange II. - Abstract: A porous coral-like zinc oxide (c-ZnO) photocatalyst was synthesized by the hydrothermal method. The coral-like structure was obtained by precipitating Zn{sub 4}(CO{sub 3})(OH){sub 6}H{sub 2}O (ZnCH), which forms nanosheets that aggregate together to form microspheres with the coral-like structure. X-ray diffraction (XRD) studies indicate that after heating at 550 C the ZnCH microspheres can be converted to ZnO microspheres with a morphology similar to that of ZnCH microspheres. Thermogravimetric analysis (TGA) shows this conversion takes place at approximately 260 C. A simple electrostatic self-assembly method has been employed to uniformly disperse Au nanoparticles (1 wt.%) on the ZnO surface. In this procedure ?-D-glucose was used to stabilize the Au nanoparticles. Scanning electron microscope images indicate that the diameter of coral-like ZnO microspheres (c-ZnO) is about 8 ?m. X-ray diffraction reveals that the ZnO is highly crystalline with a wurtzite structure and the Au metallic particles have an average size of about 13 nm. X-ray photoelectron spectroscopic (XPS) studies have confirmed the presence of ZnO and also showed that the Au is present in the metallic state. The photocatalytic degradation of Orange II dye, with either ultraviolet or visible light, is faster on Au/c-ZnO than on c-ZnO.

  6. Two-chord interferometry using 3.39 {mu}m He-Ne laser on a flux-coil-generated FRC

    SciTech Connect (OSTI)

    Gota, H.; Deng, B. H.; Gupta, D.; Kiyashko, V.; Knapp, K.; Mendoza, R.; Morehouse, M.; Bolte, N.; Roche, T.; Wessel, F.

    2010-10-15

    A two-chord {lambda}{sub IR}{approx}3.39 {mu}m He-Ne laser interferometer system was developed for a flux-coil-generated field-reversed configuration to estimate the electron density and the total temperature of the field-reversed configuration (FRC) plasma. This two-chord heterodyne interferometer system consists of a single {approx}2 mW infrared He-Ne laser, a visible ({lambda}{sub vis}{approx}632.8 nm) He-Ne laser for the alignment, a 40 MHz acousto-optic modulator, photodetectors, and quadrature phase detectors. Initial measurement was performed and the measured average electron densities were 2-10x10{sup 19} m{sup -3} at two different radial positions in the midplane. A time shift in density was observed as the FRC expands radially. The time evolution of the line-averaged density agrees with the density estimated from the in situ internal magnetic probes, based on a rigid-rotor profile model.

  7. Selection Tests of MnZn and NiZn Ferrites for Mu2e 300 kHz and 5.1 MHz AC Dipoles

    SciTech Connect (OSTI)

    Bourkland, K.; Elementi, L.; Feher, S.; Harding, D.J.; Kashikhin, V.S.; Makarov, A.; Pfeffer, H.; Velev, G.V.; Mulushev, E.; Iedmeska, I.; Venturini, M.; /Pisa U.

    2011-09-09

    Mu2e, a charged lepton flavor violation (CLFV) experiment is planned to start at Fermilab late in this decade. The proposed experiment will search for neutrinoless muon to electron conversions with unprecedented sensitivity, better than 6 x 10{sup -17 }at 90% CL. To achieve this sensitivity the incoming proton beam must be highly suppressed during the window for detecting the muon decays. The current proposal for beam extinction is based on a collimator design with two dipoles running at {approx}300 kHz and 5.1 MHz and synchronized to the proton bunch spacing. The appropriate choice of ferrite material for the magnet yoke is a critical step in the overall design of the dipoles and their reliable operation at such high frequencies over the life of the experiment. This choice, based on a series of the thermal and magnetic measurements of the ferrite samples, is discussed in the paper. Additionally, the first results from the testing at 300 kHz of a prototype AC dipole are presented.

  8. INTERMEDIATE-MASS HOT CORES AT {approx}500 AU: DISKS OR OUTFLOWS?

    SciTech Connect (OSTI)

    Palau, Aina; Girart, Josep M.; Fuente, Asuncion; Alonso-Albi, Tomas; Fontani, Francesco; Sanchez-Monge, Alvaro; Boissier, Jeremie; Pietu, Vincent; Neri, Roberto; Busquet, Gemma; Estalella, Robert; Zapata, Luis A.; Zhang, Qizhou; Ho, Paul T. P.; Audard, Marc

    2011-12-20

    Observations with the Plateau de Bure Interferometer in the most extended configuration toward two intermediate-mass star-forming regions, IRAS 22198+6336 and AFGL 5142, reveal the presence of several complex organic molecules at {approx}500 AU scales, confirming the presence of hot cores in both regions. The hot cores are not rich in CN-bearing molecules, as often seen in massive hot cores, and are mainly traced by CH{sub 3}CH{sub 2}OH, (CH{sub 2}OH){sub 2}, CH{sub 3}COCH{sub 3}, and CH{sub 3}OH, with, additionally, CH{sub 3}CHO, CH{sub 3}OD, and HCOOD for IRAS 22198+6336, and C{sub 6}H and O{sup 13}CS for AFGL 5142. The emission of complex molecules is resolved down to sizes of {approx}300 and {approx}600 AU, for IRAS 22198+6336 and AFGL 5142, respectively, and most likely is tracing protostellar disks rather than flattened envelopes or toroids as is usually found. This is especially clear for the case of IRAS 22198+6336, where we detect a velocity gradient for all the mapped molecules perpendicular to the most chemically rich outflow of the region, yielding a dynamic mass {approx}> 4 M{sub Sun }. As for AFGL 5142, the hot core emission is resolved into two elongated cores separated {approx}1800 AU. A detailed comparison of the complex molecule peaks to the new CO (2-1) data and H{sub 2}O maser data from the literature suggests also that for AFGL 5142 the complex molecules are mainly associated with disks, except for a faint and extended molecular emission found to the west, which is possibly produced in the interface between one of the outflows and the dense surrounding gas.

  9. EXPLORING INTERMEDIATE (5-40 AU) SCALES AROUND AB AURIGAE WITH THE PALOMAR FIBER NULLER

    SciTech Connect (OSTI)

    Khn, J.; Mennesson, B.; Liewer, K.; Martin, S.; Loya, F.; Serabyn, E.; Millan-gabet, R.

    2015-02-10

    We report on recent K{sub s} -band interferometric observations of the young pre-main-sequence star AB Aurigae obtained with the Palomar Fiber Nuller (PFN). Reaching a contrast of a few 10{sup 4} inside a field of view extending from 35 to 275 mas (5-40 AU at AB Aur's distance), the PFN is able to explore angular scales that are intermediate between those accessed by coronagraphic imaging and long baseline interferometry. This intermediate region is of special interest given that many young stellar objects are believed to harbor extended halos at such angular scales. Using destructive interference (nulling) between two sub-apertures of the Palomar 200 inch telescope and rotating the telescope pupil, we measured a resolved circumstellar excess at all probed azimuth angles. The astrophysical null measured over the full rotation is fairly constant, with a mean value of 1.52%, and a slight additional azimuthal modulation of 0.2%. The isotropic astrophysical null is indicative of circumstellar emission dominated by an azimuthally extended source, possibly a halo, or one or more rings of dust, accounting for several percent of the total K{sub s}-band flux. The modest azimuthal variation may be explained by some skewness or anisotropy of the spatially extended source, e.g., an elliptical or spiral geometry, or clumping, but it could also be due to the presence of a point source located at a separation of ?120 mas (17 AU) with ?6 10{sup 3} of the stellar flux. We combine our results with previous Infrared Optical Telescope Array observations of AB Aur at H band, and demonstrate that a dust ring located at ?30 mas (4.3 AU) represents the best-fitting model to explain both sets of visibilities. We are also able to test a few previously hypothesized models of the incoherent component evident at longer interferometric baselines.

  10. Top-emission Si-based phosphor organic light emitting diode with Au doped ultrathin n-Si film anode and bottom Al mirror

    SciTech Connect (OSTI)

    Li, Y. Z.; Xu, W. J.; Ran, G. Z. [State Key Laboratory for Mesoscopic Physics, School of Physics, Peking University, Beijing 100871 (China); Qin, G. G. [State Key Laboratory for Mesoscopic Physics, School of Physics, Peking University, Beijing 100871 (China); Key Lab of Semiconductor Materials, CAS, Beijing 100083 (China)

    2009-07-20

    We report a highly efficient top-emission Si-based phosphor organic light emitting diode (PhOLED) with an ultrathin polycrystalline n-Si:Au film anode and a bottom Al mirror. This anode is formed by magnetron sputtering followed by Ni induced crystallization and then Au diffusion. By optimizing the thickness of the n-Si:Au film anode, the Au diffusion temperature, and the other parameters of the PhOLED, the highest current and power efficiencies of the n-Si:Au film anode PhOLED reached 85{+-}9 cd/A and 80{+-}8 lm/W, respectively, corresponding to an external quantum efficiency of 21{+-}2% and a power conversion efficiency of 15{+-}2%, respectively, which are about 60% and 110% higher than those of the indium tin oxide anode counterpart and 70% and 50% higher than those of the bulk n{sup +}-Si:Au anode counterpart, respectively.

  11. ARM Climate Modeling Best Estimate From Darwin, AU (ARMBE-ATM TWPC2)

    Office of Scientific and Technical Information (OSTI)

    (Dataset) | Data Explorer TWPC2) Title: ARM Climate Modeling Best Estimate From Darwin, AU (ARMBE-ATM TWPC2) The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data. Authors: McCoy, Renata ; Xie, Shaocheng Publication Date: 2013-12-26 OSTI Identifier: 1111568 DOE Contract Number: DE-AC05-00OR22725 Resource Type: Dataset Data Type: Numeric Data Research Org: Atmospheric Radiation

  12. ARM Climate Modeling Best Estimate From Darwin, AU (ARMBE-ATM TWPC3)

    Office of Scientific and Technical Information (OSTI)

    (Dataset) | Data Explorer TWPC3) Title: ARM Climate Modeling Best Estimate From Darwin, AU (ARMBE-ATM TWPC3) The ARM CMBE-ATM [Xie, McCoy, Klein et al.] data file contains a best estimate of several selected atmospheric quantities from ACRF observations and NWP analysis data. Authors: McCoy, Renata ; Xie, Shaocheng Publication Date: 2013-12-27 OSTI Identifier: 1111571 DOE Contract Number: DE-AC05-00OR22725 Resource Type: Dataset Data Type: Numeric Data Research Org: Atmospheric Radiation

  13. The Correlation of Stress-State and Nano-Mechanical Properties in Au

    SciTech Connect (OSTI)

    HOUSTON,JACK E.; JARAUSCH,K.F.; KIELY,J.D.; RUSSELL,P.E.

    1999-10-07

    A dependence of elastic response on the stress-state of a thin film has been demonstrated using the interfacial force microscope (IFM). Indentation response was measured as a function of the applied biaxial stress-state for 100 nm thick Au films. An increase in measured elastic modulus with applied compressive stress, and a decrease with applied tensile stress was observed. Measurements of elastic modulus before and after applying stress were identical indicating that the observed change in response is not due to a permanent change in film properties.

  14. Angular distribution and recoil effect for 1 MeV Au+ ions through a Si3N4 thin foil

    SciTech Connect (OSTI)

    Jin, Ke; Zhu, Zihua; Manandhar, Sandeep; Liu, Jia; Chen, Chien-Hung; Shutthanandan, Vaithiyalingam; Thevuthasan, Suntharampillai; Weber, William J; Zhang, Yanwen

    2014-01-01

    The Stopping and Range of Ions in Matter (SRIM) code has been widely used to predict nuclear stopping power and angular distribution of ion-solid collisions. However, experimental validation of the predictions is insufficient for slow heavy ions in nonmetallic compounds. In this work, time-of-flight secondary ion mass spectrometry (ToF-SIMS) is applied to determine the angular distribution of 1 MeV Au ions after penetrating a Si3N4 foil with a thickness of ~100 nm. The exiting Au ions are collected by a Si wafer located ~14 mm behind the Si3N4 foil, and the resulting 2-dimensional distribution of Au ions on the Si wafer is measured by ToF-SIMS. The SRIM-predicted angular distribution of Au ions through the Si3N4 thin foil is compared with the measured results, indicating that SRIM slightly overestimates the nuclear stopping power by up to 10%. In addition, thickness reduction of the suspended Si3N4 foils induced by 1 MeV Au ion irradiation is observed with an average loss rate of ~107 atom/ion.

  15. Tailoring characteristic thermal stability of Ni-Au binary nanocrystals via structure and composition engineering: theoretical insights into structural evolution and atomic inter-diffusion

    SciTech Connect (OSTI)

    Li, Bangquan; Wang, Hailong; Xing, Guozhong; Wang, Rongming E-mail: rmwang@ustb.edu.cn

    2014-11-15

    We report on the structural evolution and atomic inter-diffusion characteristics of the bimetallic Ni-Au nanocrystals (NCs) by molecular dynamics simulations studies. Our results reveal that the thermal stability dynamics of Ni-Au NCs strongly depends on the atomic configurations. By engineering the structural construction with Ni:Au = 1:1 atomic composition, compared with core-shell Au@Ni and alloy NCs, the melting point of core-shell Ni@Au NCs is significantly enhanced up to 1215 K. Unexpectedly, with atomic ratio of Au:Ni= 1:9, the melting process initiates from the atoms in the shell of Ni@Au and alloy NCs, while starts from the core of Au@Ni NCs. The corresponding features and evolution process of structural motifs, mixing and segregation are illustrated via a series of dynamic simulations videos. Moreover, our results revealed that the face centered cubic phase Au{sub 0.75}Ni{sub 0.25} favorably stabilizes in NCs form but does not exist in the bulk counterpart, which elucidates the anomalies of previously reported experimental results on such bimetallic NCs.

  16. System size dependence of cluster properties from two-particle angular correlations in Cu+Cu and Au+Au collisions at sq root(s{sub NN})=200 GeV

    SciTech Connect (OSTI)

    Alver, B.; Ballintijn, M.; Busza, W.; Gulbrandsen, K.; Henderson, C.; Kane, J. L.; Kulinich, P.; Li, W.; Loizides, C.; Reed, C.; Roland, C.; Roland, G.; Stephans, G. S. F.; Nieuwenhuizen, G. J. van; Vaurynovich, S. S.; Verdier, R.; Veres, G. I.; Wenger, E.; Wyslouch, B.; Back, B. B.

    2010-02-15

    We present results on two-particle angular correlations in Cu+Cu and Au+Au collisions at a center-of-mass energy per nucleon pair of 200 GeV over a broad range of pseudorapidity (eta) and azimuthal angle (phi) values as a function of collision centrality. The PHOBOS detector at the Relativistic Heavy Ion Collider has a uniquely large angular coverage for inclusive charged particles, which allows for the study of correlations on both long- and short-range scales. A complex two-dimensional correlation structure in {Delta}{eta} and {Delta}{phi} emerges, which is interpreted in the context of a cluster model. The effective cluster size and decay width are extracted from the two-particle pseudorapidity correlation functions. The effective cluster size found in semicentral Cu+Cu and Au+Au collisions is comparable to that found in proton-proton collisions but a nontrivial decrease in size with increasing centrality is observed. Moreover, a comparison of results from Cu+Cu versus Au+Au collisions shows an interesting scaling of the effective cluster size with the measured fraction of total cross section (which is related to the ratio of the impact parameter to the nuclear radius, b/2R), suggesting a geometric origin. Further analysis for pairs from restricted azimuthal regions shows that the effective cluster size at {Delta}{phi}{approx}180 deg. drops more rapidly toward central collisions than the size at {Delta}{phi}{approx}0 deg. The effect of limited {eta} acceptance on the cluster parameters is also addressed, and a correction is applied to present cluster parameters for full {eta} coverage, leading to much larger effective cluster sizes and widths than previously noted in the literature. These results should provide insight into the hot and dense medium created in heavy ion collisions.

  17. Oxidation of palladium on Au(111) and ZnO(0001) supports

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Lallo, J.; Tenney, S. A.; Kramer, A.; Sutter, P.; Batzill, M.

    2014-10-21

    The oxidation of supported Pd-deposits on Au(111) and ZnO(0001) single crystals has been studied by x- ray photoemission spectroscopy (XPS). Oxidation has been carried out ex-situ in a high-pressure cell with subsequent vacuum-transfer and characterization by XPS in ultrahigh vacuum (UHV), as well as using in-situ characterization by synchrotron based near-ambient pressure XPS. On Au(111) alloying of Pd with the substrate competes with oxidation and only sufficiently thick Pd films have been found to oxidize. For Pd on ZnO the oxidation conditions depend on the amount of deposited Pd. Thicker Pd deposits behave similar to bulk Pd, while thinner filmsmore » oxidize already at lower temperatures. Interestingly, for very small amounts of Pd, in-situ XPS shows full oxidation at room temperature and at less than 0.6 mbar O₂ pressure. This indicates a lowering of the kinetic barriers for oxidation of very small supported Pd-clusters. The formed oxide is, however, not stable in UHV and a slow reduction is observed. The instability of this oxide indicates that the Pd-oxide formed at the interface to ZnO may have different chemical properties compared to bulk PdO or surface oxides on Pd.« less

  18. OBSERVATIONS OF ISOTROPIC INTERSTELLAR PICK-UP IONS AT 11 AND 17 AU FROM NEW HORIZONS

    SciTech Connect (OSTI)

    Randol, B. M.; McComas, D. J.; Elliott, H. A.; Gosling, J. T.; Schwadron, N. A.

    2012-08-10

    We report new observations by the Solar Wind Around Pluto (SWAP) instrument on the New Horizons spacecraft of an energy-per-charge (E/q) spectrum of interstellar pick-up ions (PUIs) from an unprecedented heliocentric distance of 17 AU. This E/q spectrum is fit well by an isotropic PUI distribution function combined with the detailed response of the SWAP instrument. In contrast to earlier work, we are also able to fit an isotropic PUI model to an E/q spectrum measured by SWAP at 11.3 AU by explicitly including two additional effects. These are (1) the E/q-dependent geometric factor of SWAP, which increases with decreasing E/q owing to effects associated with the post-acceleration of particles exiting the electrostatic analyzer portion of the instrument; and (2) a solar wind distribution, the model spectrum of which contributes significantly to the low-E/q part of the overall model owing, presumably, to secondary particles produced within the instrument.

  19. Oxidation of palladium on Au(111) and ZnO(0001) supports

    SciTech Connect (OSTI)

    Lallo, J.; Tenney, S. A.; Kramer, A.; Sutter, P.; Batzill, M.

    2014-10-21

    The oxidation of supported Pd-deposits on Au(111) and ZnO(0001) single crystals has been studied by x- ray photoemission spectroscopy (XPS). Oxidation has been carried out ex-situ in a high-pressure cell with subsequent vacuum-transfer and characterization by XPS in ultrahigh vacuum (UHV), as well as using in-situ characterization by synchrotron based near-ambient pressure XPS. On Au(111) alloying of Pd with the substrate competes with oxidation and only sufficiently thick Pd films have been found to oxidize. For Pd on ZnO the oxidation conditions depend on the amount of deposited Pd. Thicker Pd deposits behave similar to bulk Pd, while thinner films oxidize already at lower temperatures. Interestingly, for very small amounts of Pd, in-situ XPS shows full oxidation at room temperature and at less than 0.6 mbar O? pressure. This indicates a lowering of the kinetic barriers for oxidation of very small supported Pd-clusters. The formed oxide is, however, not stable in UHV and a slow reduction is observed. The instability of this oxide indicates that the Pd-oxide formed at the interface to ZnO may have different chemical properties compared to bulk PdO or surface oxides on Pd.

  20. Sintered Cr/Pt and Ni/Au ohmic contacts to B12P2

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Frye, Clint D.; Kucheyev, Sergei O.; Edgar, James H.; Voss, Lars F.; Conway, Adam M.; Shao, Qinghui; Nikolic, Rebecca J.

    2015-04-09

    With this study, icosahedral boron phosphide (B12P2) is a wide-bandgap semiconductor possessing interesting properties such as high hardness, chemical inertness, and the reported ability to self-heal from irradiation by high energy electrons. Here, the authors developed Cr/Pt and Ni/Au ohmic contacts to epitaxially grown B12P2 for materials characterization and electronic device development. Cr/Pt contacts became ohmic after annealing at 700 °C for 30 s with a specific contact resistance of 2×10–4 Ω cm2, as measured by the linear transfer length method. Ni/Au contacts were ohmic prior to any annealing, and their minimum specific contact resistance was ~l–4 × 10–4 Ωmore » cm2 after annealing over the temperature range of 500–800 °C. Rutherford backscattering spectrometry revealed a strong reaction and intermixing between Cr/Pt and B12P2 at 700 °C and a reaction layer between Ni and B12P2 thinner than ~25 nm at 500 °C.« less

  1. The (111) Surface of NaAu2. Structure, Composition, and Stability

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kwolek, Emma J.; Widmer, Roland; Gröning, Oliver; Deniz, Okan; Walen, Holly; Yuen, Chad D.; Huang, Wenyu; Schlagel, Deborah L.; Wallingford, Mark; Thiel, Patricia A.

    2014-12-17

    The (111) surface of single-crystal NaAu2 is a model for catalytically active, powdered NaAu2. We prepare and characterize this surface with a broad suite of techniques. Preparation in ultrahigh vacuum consists of the traditional approach of ion bombardment (to remove impurities) and thermal annealing (to restore surface order). Both of these steps cause loss of sodium (Na), and repeated treatments eventually trigger conversion of the surface and near-surface regions to crystalline gold. The bulk has a limited ability to repopulate the surface Na. Under conditions where Na depletion is minimized, electron diffraction patterns are consistent with the bulk-terminated structure, andmore » scanning tunneling microscopy reveals mesa-like features with lateral dimensions of a few tens of nanometers. The tops of the mesas do not possess fine structure characteristic of a periodic lattice, suggesting that the surface layer is disordered under the conditions of these experiments.« less

  2. Ab initio study of MXe{sub n}{sup +} (M=Cu, Ag, and Au; n=1,2)

    SciTech Connect (OSTI)

    Li Xinying; Cao Xue

    2008-02-15

    The equilibrium geometries, vibrational frequencies, dissociation energies, and populations of the title species were studied at Hartree-Fock (HF), second-order Moeller-Plesset (MP2), and coupled-cluster singles-doubles (triples) [CCSD(T)] levels. The electron correlation effects and relativistic effects on the geometry and stability were investigated at the CCSD(T) level. Both effects stabilize title species. The populations analyses show that M-Xe bonding is dominated by electrostatic interactions and the best theoretical estimate of the dissociation energies are 1.104 and 2.260 eV for AuXe{sup +} and AuXe{sub 2}{sup +}, respectively. The Cu and Ag are weakly bonded to Xe compared to Au.

  3. Au133(SPh-tBu)52 Nanomolecules: X-ray Crystallography, Optical, Electrochemical, and Theoretical Analysis

    SciTech Connect (OSTI)

    Dass, Amala; Theivendran, Shevanuja; Nimmala, Praneeth Reddy; Kumara, Chanaka; Jupally, Vijay Reddy; Fortunelli, Alessandro; Sementa, Luca; Barcaro, Giovanni; Zuo, Xiaobing; Noll, Bruce C.

    2015-04-15

    Crystal structure determination has revolutionized modern science in biology, chemistry, and physics. However, the difficulty in obtaining periodic crystal lattices which are needed for X-ray crystal analysis has hindered the determination of atomic structure in nanomaterials, known as the nanostructure problem. Here, by using rigid and bulky ligands, we have overcome this limitation and successfully solved the X-ray crystallographic structure of the largest reported thiolated gold nanomolecule, Au133S52. The total composition, Au133(SPh-tBu)52, was verified using high resolution electrospray ionization mass spectrometry (ESI-MS). The experimental and simulated optical spectra show an emergent surface plasmon resonance that is more pronounced than in the slightly larger Au144(SCH2CH2Ph)60. Theoretical analysis indicates that the presence of rigid and bulky ligands is the key to the successful crystal formation.

  4. Adsorption and switching properties of a N-benzylideneaniline based molecular switch on a Au(111) surface

    SciTech Connect (OSTI)

    Ovari, Laszlo; Luo, Ying; Haag, Rainer; Leyssner, Felix; Tegeder, Petra; Wolf, Martin

    2010-07-28

    High resolution electron energy loss spectroscopy has been employed to analyze the adsorption geometry and the photoisomerization ability of the molecular switch carboxy-benzylideneaniline (CBA) adsorbed on Au(111). CBA on Au(111) adopts a planar (trans) configuration in the first monolayer (ML) as well as for higher coverages (up to 6 ML), in contrast to the strongly nonplanar geometry of the molecule in solution. Illumination with UV light of CBA in direct contact with the Au(111) surface ({<=}1 ML) caused no changes in the vibrational structure, whereas at higher coverages (>1 ML) pronounced modifications of vibrational features were observed, which we assign to a trans{yields}cis isomerization. Thermal activation induced the back reaction to trans-CBA. We propose that the photoisomerization is driven by a direct (intramolecular) electronic excitation of the adsorbed CBA molecules in the second ML (and above) analogous to CBA in the liquid phase.

  5. Proton form factor ratio, {mu}{sub p}G{sub E}{sup P}/G{sub M}{sup P} from double spin asymmetry

    SciTech Connect (OSTI)

    Habarakada Liyanage, Anusha Pushpakumari

    2013-08-01

    The form factors are fundamental properties of the nucleon representing the effect of its structure on its response to electromagnetic probes such as electrons. They are functions of the four-momentum transfer squared Q{sup 2} between the electron and the proton. This thesis reports the results of a new measurement of the ratio of the electric and magnetic form factors of the proton up to Q{sup 2} = 5.66 (GeV/c){sup 2} using the double spin asymmetry with a polarized beam and target. Experiment E07-003 (SANE, Spin Asymmetries of the Nucleon Experiment) was carried out in Hall C at Jefferson Lab in 2009 to study the proton spin structure functions with a dynamically polarized ammonia target and longitudinally polarized electron beam. By detecting elastically scattered protons in the High-Momentum Spectrometer (HMS) in coincidence with the electrons in the Big Electron Telescope Array (BETA), elastic measurements were carried out in parallel. The elastic double spin asymmetry allows one to extract the proton electric to magnetic form factor ratio G{sup p}{sub E}/G{sup p}{sub M} at high-momentum transfer, Q{sup 2} = 5.66 (GeV/c){sup 2}. In addition to the coincidence data, inclusively scattered electrons from the polarized ammonia target were detected by HMS, which allows to measure the beam-target asymmetry in the elastic region with the target spin nearly perpendicular to the momentum transfer, and to extract G{sup p}{sub E}/G{sup p}{sub M} at low Q{sup 2} = 2.06 (GeV/c){sup 2}. This alternative measurement of G{sup p}{sub E}/G{sup p}{sub M} has verified and confirmed the dramatic discrepancy at high Q{sup 2} between the Rosenbluth and the recoil-polarization-transfer iv method with a different measurement technique and systematic uncertainties uncorrelated to those of the recoil-polarization measurements. The measurement of the form factor ratio at Q{sup 2} = 2.06 (GeV/c){sup 2} has been determined as {mu}{sub p}G{sup p}{sub E}/G{sup p}{sub M} = 0.605{+-}0.178{sub stat}{+-}0.033{sub sys} which is in agreement with an earlier measurement with the polarized target technique at similar kinematics. The measurement of the form factor ratio at Q{sup 2} = 5.66 (GeV/c){sup 2} has been determined as {mu}{sub p}G{sup p}{sub E}/G{sup p}{sub M} = 0.672 {+-} 0.362{sub stat} which represents the highest Q{sup 2} reach with the double spin asymmetry to date.

  6. ON THE WEAK-WIND PROBLEM IN MASSIVE STARS: X-RAY SPECTRA REVEAL A MASSIVE HOT WIND IN {mu} COLUMBAE

    SciTech Connect (OSTI)

    Huenemoerder, David P.; Oskinova, Lidia M.; Todt, Helge; Ignace, Richard; Waldron, Wayne L.; Hamaguchi, Kenji

    2012-09-10

    {mu} Columbae is a prototypical weak-wind O star for which we have obtained a high-resolution X-ray spectrum with the Chandra LETG/ACIS instrument and a low-resolution spectrum with Suzaku. This allows us, for the first time, to investigate the role of X-rays on the wind structure in a bona fide weak-wind system and to determine whether there actually is a massive hot wind. The X-ray emission measure indicates that the outflow is an order of magnitude greater than that derived from UV lines and is commensurate with the nominal wind-luminosity relationship for O stars. Therefore, the {sup w}eak-wind problem{sup -}identified from cool wind UV/optical spectra-is largely resolved by accounting for the hot wind seen in X-rays. From X-ray line profiles, Doppler shifts, and relative strengths, we find that this weak-wind star is typical of other late O dwarfs. The X-ray spectra do not suggest a magnetically confined plasma-the spectrum is soft and lines are broadened; Suzaku spectra confirm the lack of emission above 2 keV. Nor do the relative line shifts and widths suggest any wind decoupling by ions. The He-like triplets indicate that the bulk of the X-ray emission is formed rather close to the star, within five stellar radii. Our results challenge the idea that some OB stars are 'weak-wind' stars that deviate from the standard wind-luminosity relationship. The wind is not weak, but it is hot and its bulk is only detectable in X-rays.

  7. Measurement of transmission efficiency for 400 MeV proton beam through collimator at Fermilab MuCool Test Area using Chromox-6 scintillation screen

    SciTech Connect (OSTI)

    Jana, M. R.; Chung, M.; Leonova, M.; Moretti, A.; Palmer, M.; Schwarz, T.; Tollestrup, A.; Yonehara, K.; Freemire, B.; Hanlet, P.; Torun, Y.

    2013-06-15

    The MuCool Test Area (MTA) at Fermilab is a facility to develop the technology required for ionization cooling for a future Muon Collider and/or Neutrino Factory. As part of this research program, feasibility studies of various types of RF cavities in a high magnetic field environment are in progress. As a unique approach, we have tested a RF cavity filled with a high pressure hydrogen gas with a 400 MeV proton beam in an external magnetic field (B = 3 T). Quantitative information about the number of protons passing through this cavity is an essential requirement of the beam test. The MTA is a flammable gas (hydrogen) hazard zone. Due to safety reasons, no active (energized) beam diagnostic instrument can be used. Moreover, when the magnetic field is on, current transformers (toroids) used for beam intensity measurements do not work due to the saturation of the ferrite material of the transformer. Based on these requirements, we have developed a passive beam diagnostic instrumentation using a combination of a Chromox-6 scintillation screen and CCD camera. This paper describes details of the beam profile and position obtained from the CCD image with B = 0 T and B = 3 T, and for high and low intensity proton beams. A comparison is made with beam size obtained from multi-wires detector. Beam transmission efficiency through a collimator with a 4 mm diameter hole is measured by the toroids and CCD image of the scintillation screen. Results show that the transmission efficiency estimated from the CCD image is consistent with the toroid measurement, which enables us to monitor the beam transmission efficiency even in a high magnetic field environment.

  8. The Golden Crown: A Single Au Atom that Boosts the CO Oxidation Catalyzed by a Palladium Cluster on Titania Surfaces

    SciTech Connect (OSTI)

    Zhang, Jin; Alexandrova, Anastassia N.

    2013-07-18

    We show that at the subnano scale, the catalytic properties of surface-supported clusters can be majorly impacted by strategic doping and the choice for the supporting surface. This is a first-principles investigation of CO oxidation catalyzed by two subnanoclusters, Pd4Au and Pd5, deposited on rutile TiO2(110) surfaces. The titania surface was found to participate in the reaction directly via providing additional reaction pathways. The bimetallic cluster Pd4Au shows enhanced catalytic activity, whereas the monometallic Pd5 is poisoned and deactivated in the presence of CO and oxygen, and this trend is reversed from that in the gas phase.

  9. Microsoft Word - AU Funtional Area Points of Contact by Office Directors- Rev 1 04-28-15

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Functional Area Points of Contact Listing by AU Office Director Page 1 of 11 Integrated AU-1.2, -10, -20, -50 - August 21, 2014 Function/Subject Director Email Phone Accident Investigations Andy Lawrence Andrew.lawrence@hq.doe.gov (202) 586-6740 Administrative Review (Clearance eligibility determinations) Robert Lingan Robert.lingan@hq.doe.gov (202) 586-1461 Annual Report to Congress on Special Nuclear Material Robert Lingan Robert.lingan@hq.doe.gov (202) 586-1461 Annual Site Environmental

  10. Switching of the photonic band gap in three-dimensional film photonic crystals based on opal-VO{sub 2} composites in the 1.3-1.6 {mu}m spectral range

    SciTech Connect (OSTI)

    Pevtsov, A. B. Grudinkin, S. A.; Poddubny, A. N.; Kaplan, S. F.; Kurdyukov, D. A.; Golubev, V. G.

    2010-12-15

    The parameters of three-dimensional photonic crystals based on opal-VO{sub 2} composite films in the 1.3-1.6 {mu}m spectral range important for practical applications (Telecom standard) are numerically calculated. For opal pores, the range of filling factors is established (0.25-0.6) wherein the composite exhibits the properties of a three-dimensional insulator photonic crystal. On the basis of the opal-VO{sub 2} composites, three-dimensional photonic film crystals are synthesized with specified parameters that provide a maximum shift of the photonic band gap in the vicinity of the wavelength {approx}1.5 {mu}m ({approx}170 meV) at the semiconductor-metal transition in VO{sub 2}.

  11. Nuclear matter effects on J/ψ production in asymmetric Cu + Au collisions at \\(\\sqrt{s_{\\mathrm{NN}}} = 200\\) GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adare, A.; Aidala, C.; Ajitanand, N. N.; Akiba, Y.; Akimoto, R.; Alexander, J.; Alfred, M.; Aoki, K.; Apadula, N.; Aramaki, Y.; et al

    2014-12-18

    We report on J/ψ production from asymmetric Cu+Au heavy-ion collisions at \\(\\sqrt{s_{\\mathrm{NN}}} = 200\\) GeV at the Relativistic Heavy Ion Collider at both forward (Cu-going direction) and backward (Au-going direction) rapidities. The nuclear modification of J/ψ yields in Cu+Au collisions in the Au-going direction is found to be comparable to that in Au+Au collisions when plotted as a function of the number of participating nucleons. In the Cu-going direction, J/ψ production shows a stronger suppression. This difference is comparable in magnitude and has the same sign as the difference expected from shadowing effects due to stronger low-x gluon suppression inmore » the larger Au nucleus. Thus, the relative suppression is opposite to that expected from hot nuclear matter dissociation, since a higher energy density is expected in the Au-going direction.« less

  12. Gold-rich R3Au7Sn3: Establishing the interdependence between electronic features and physical properties

    SciTech Connect (OSTI)

    Provino, Alessia; Steinberg, Simon; Smetana, Volodymyr; Kulkarni, Ruta; Dhar, Sudesh K.; Manfrinetti, Pietro; Mudring, Anja -Verena

    2015-05-18

    Two new polar intermetallic compounds Y3Au7Sn3 (I) and Gd3Au7Sn3 (II) have been synthesized and their structures have been determined by single crystal X-ray diffraction (P63/m; Z = 2, a = 8.148(1)/8.185(3), and c = 9.394(2)/9.415(3) for I/II, respectively). They can formally be assigned to the Cu10Sn3 type and consist of parallel slabs of Sn centered, edge-sharing trigonal Au6 antiprisms connected through R3 (R = Y, Gd) triangles. Additional Au atoms reside in the centres of trigonal Au6 prisms forming Au@Au6 clusters with Au–Au distances of 2.906–2.960 Å, while the R–R contacts in the R3 groups are considerably larger than the sums of their metallic radii. These exclusive structural arrangements provide alluring systems to study the synergism between strongly correlated systems, particularly, those in the structure of (II), and extensive polar intermetallic contacts, which has been inspected by measurements of the magnetic properties, heat capacities and electrical conductivities of both compounds. Gd3Au7Sn3 shows an antiferromagnetic ordering at 13 K, while Y3Au7Sn3 is a Pauli paramagnet and a downward curvature in its electrical resistivity at about 1.9 K points to a superconducting transition. DFT-based band structure calculations on R3Au7Sn3 (R = Y, Gd) account for the results of the conductivity measurements and different spin ordering models of (II) provide conclusive hints about its magnetic structure. As a result, chemical bonding analyses of both compounds indicate that the vast majority of bonding originates from the heteroatomic Au–Gd and Au–Sn interactions, while homoatomic Au–Au bonding is evident within the Au@Au6 clusters.

  13. Six-dimensional quantum dynamics study for the dissociative adsorption of HCl on Au(111) surface

    SciTech Connect (OSTI)

    Liu, Tianhui; Fu, Bina; Zhang, Dong H.

    2013-11-14

    The six-dimensional quantum dynamics calculations for the dissociative chemisorption of HCl on Au(111) are carried out using the time-dependent wave-packet approach, based on an accurate PES which was recently developed by neural network fitting to density functional theory energy points. The influence of vibrational excitation and rotational orientation of HCl on the reactivity is investigated by calculating the exact six-dimensional dissociation probabilities, as well as the four-dimensional fixed-site dissociation probabilities. The vibrational excitation of HCl enhances the reactivity and the helicopter orientation yields higher dissociation probability than the cartwheel orientation. A new interesting site-averaged effect is found for the title molecule-surface system that one can essentially reproduce the six-dimensional dissociation probability by averaging the four-dimensional dissociation probabilities over 25 fixed sites.

  14. Assembly/Disassembly of DNA-Au Nanoparticles: A Strategy of Intervention

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Lim, I-Im S.; Wang, Lingyan; Chandrachud, Uma; Gal, Susannah; Zhong, Chuan-Jian

    2008-01-01

    This report describes the viability of a strategy for manipulating the assembly/disassembly processes of DNA-Au nanoparticles by molecular intervention. Using the temperature-induced assembly and disassembly processes of DNAs and gold nanoparticles as a model system, the introduction of a molecular recognition probe is demonstrated to lead to the intervention of the assembly/disassembly processes depending on its specific biorecognition. This process can be detected by monitoring the change in the optical properties of gold nanoparticles and their DNA assemblies. Implications of the preliminary results to exploration of the resulting nanostructures for fine-tuning of the interfacial reactivities in DNA-based bioassays and biomaterialmore » engineering are also discussed.« less

  15. Random telegraph signals by alkanethiol-protected Au nanoparticles in chemically assembled single-electron transistors

    SciTech Connect (OSTI)

    Kano, Shinya; Azuma, Yasuo; Tanaka, Daisuke; Sakamoto, Masanori; Teranishi, Toshiharu; Smith, Luke W.; Smith, Charles G.; Majima, Yutaka

    2013-12-14

    We have studied random telegraph signals (RTSs) in a chemically assembled single-electron transistor (SET) at temperatures as low as 300 mK. The RTSs in the chemically assembled SET were investigated by measuring the sourcedrain current, using a histogram of the RTS dwell time, and calculating the power spectrum density of the drain currenttime characteristics. It was found that the dwell time of the RTS was dependent on the drain voltage of the SET, but was independent of the gate voltage. Considering the spatial structure of the chemically assembled SET, the origin of the RTS is attributed to the trapped charges on an alkanethiol-protected Au nanoparticle positioned near the SET. These results are important as they will help to realize stable chemically assembled SETs in practical applications.

  16. Voyager 2 observations of plasmas and flows out to 104 AU

    SciTech Connect (OSTI)

    Richardson, J. D.; Decker, R. B. E-mail: robert.decker@apljhu.edu

    2014-09-10

    Voyager 2 has crossed through 20 AU of the heliosheath; assuming the same heliosheath thickness as at Voyager 1, it is now two-thirds of the way to the heliopause. The plasma data are generally of good quality, although the increasing flow angle of the plasma makes analysis more difficult. The average plasma speed has remained constant but the flow angles have increased to almost 60 in the RT plane and to almost 30 in the RN plane. The average density and thermal speed have been constant since a density increase observed in 2011. Comparison of V2 plasma flows derived from plasma science experiment (PLS) data and Low Energy Charged Particle (LECP) proton anisotropies give good agreement except when heavy ion contributions or non-convective proton anisotropies are observed in the LECP data.

  17. Exploring the activity of a novel Au/TiC(001) model catalyst towards CO and CO2 hydrogenation

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Asara, Gian Giacomo; Ricart, Josep M.; Rodriguez, Jose A.; Illas, Francesc

    2015-02-02

    Small metallic nanoparticles supported on transition metal carbides exhibit an unexpected high activity towards a series of chemical reactions. In particular, the Au/TiC system has proven to be an excellent catalyst for SO2 decomposition, thiophene hydrodesulfurization, O2 and H2 dissociation and the water gas shift reaction. Recent studies have shown that Au/TiC is a very good catalyst for the reverse water–gas shift (CO2 + H2 → CO + H2O) and CO2 hydrogenation to methanol. The present work further expands the range of applicability of this novel type of systems by exploring the catalytic activity of Au/TiC towards the hydrogenation ofmore » CO or CO2 with periodic density functional theory (DFT) calculations on model systems. Hydrogen dissociates easily on Au/TiC but direct hydrogenation of CO to methanol is hindered by very high activation barriers implying that, on this model catalyst, methanol production from CO2 involves the hydrogenation of a HOCO-like intermediate. Thus, when dealing with mixtures of syngas (CO/CO2/H2/H2O), CO could be transformed into CO2 through the water gas shift reaction with subsequent hydrogenation of CO2 to methanol.« less

  18. Interstaple Dithiol Cross-Linking in Au(25)(SR)(18) Nanomolecules: A Combined Mass Spectrometric and Computational Study

    SciTech Connect (OSTI)

    Jiang, Deen; Dass, Amala; Tschumper, Gregory; Mattern, Daniell; Van Dornshuld, Eric; Kota, Rajesh; Jupally, Vijay

    2011-01-01

    A systematic study of cross-linking chemistry of the Au{sub 25}(SR){sub 18} nanomolecule by dithiols of varying chain length, HS-(CH2)n-SH where n = 2, 3, 4, 5, and 6, is presented here. Monothiolated Au{sub 25} has six [RSAuSRAuSR] staple motifs on its surface, and MALDI mass spectrometry data of the ligand exchanged clusters show that propane (C3) and butane (C4) dithiols have ideal chain lengths for interstaple cross-linking and that up to six C3 or C4 dithiols can be facilely exchanged onto the cluster surface. Propanedithiol predominately exchanges with two monothiols at a time, making cross-linking bridges, while butanedithiol can exchange with either one or two monothiols at a time. The extent of cross-linking can be controlled by the Au{sub 25}(SR){sub 18} to dithiol ratio, the reaction time of ligand exchange, or the addition of a hydrophobic tail to the dithiol. MALDI MS suggests that during ethane (C2) dithiol exchange, two ethanedithiols become connected by a disulfide bond; this result is supported by density functional theory (DFT) prediction of the optimal chain length for the intrastaple coupling. Both optical absorption spectroscopy and DFT computations show that the electronic structure of the Au{sub 25} nanomolecule retains its main features after exchange of up to eight monothiol ligands.

  19. Inter-staple Dithiol Crosslinking in Au25(SR)18 Nanomolecules: A Combined Mass Spectrometric and Computational Study

    SciTech Connect (OSTI)

    Dass, Amala; Jiang, Deen; Jupally, Vijay; Kota, Rajesh; Mattern, Daniell; Tschumper, Gregory; Van Dornshuld, Eric

    2011-01-01

    A systematic study of cross-linking chemistry of the Au{sub 25}(SR){sub 18} nanomolecule by dithiols of varying chain length, HS-(CH{sub 2}){sub n}-SH where n = 2, 3, 4, 5, and 6, is presented here. Monothiolated Au{sub 25} has six [RSAuSRAuSR] staple motifs on its surface, and MALDI mass spectrometry data of the ligand exchanged clusters show that propane (C3) and butane (C4) dithiols have ideal chain lengths for interstaple cross-linking and that up to six C3 or C4 dithiols can be facilely exchanged onto the cluster surface. Propanedithiol predominately exchanges with two monothiols at a time, making cross-linking bridges, while butanedithiol can exchange with either one or two monothiols at a time. The extent of cross-linking can be controlled by the Au{sub 25}(SR){sub 18} to dithiol ratio, the reaction time of ligand exchange, or the addition of a hydrophobic tail to the dithiol. MALDI MS suggests that during ethane (C2) dithiol exchange, two ethanedithiols become connected by a disulfide bond; this result is supported by density functional theory (DFT) prediction of the optimal chain length for the intrastaple coupling. Both optical absorption spectroscopy and DFT computations show that the electronic structure of the Au{sub 25} nanomolecule retains its main features after exchange of up to eight monothiol ligands.

  20. Memorandum, AU-1 Clarification on the Drug Testing Custody and Control Form for Department of Energy Contractors

    Broader source: Energy.gov [DOE]

    Memorandum from Matthew Moury, AU-1 clarifying the drug testing custody and control form for DOE contractors. This memo clarifies the correct form for DOE contractors to use when submitting their samples to a drug testing facility in accordance with 10 CFR part 707, Workplace Substance Programs at DOE Sites

  1. Visible light plasmonic heating of Au-ZnO for the catalytic reduction of CO{sub 2}

    SciTech Connect (OSTI)

    Wang, Congjun; Ranasingha, Oshadha; Natesakhawat, Sittichai; Ohodnicki, Paul R.; Ohodnicki, Andio, Mark; Lewis, James; P Matranga, Christopher

    2013-05-01

    Plasmonic excitation of Au nanoparticles attached to the surface of ZnO catalysts using low power 532 nm laser illumination leads to significant heating of the catalyst and the conversion of CO{sub 2} and H{sub 2} reactants to CH{sub 4} and CO products. Temperature-calibrated Raman spectra of ZnO phonons show that intensity-dependent plasmonic excitation can controllably heat AuZnO from 30 to #1;~600 {degrees}#3;C and simultaneously tune the CH{sub 4} : CO product ratio. The laser induced heating and resulting CH{sub 4} : CO product distribution agrees well with predictions from thermodynamic models and temperatureprogrammed reaction experiments indicating that the reaction is a thermally driven process resulting from the plasmonic heating of the AuZnO. The apparent quantum yield for CO{sub 2} conversion under continuous wave (cw) 532 nm laser illumination is 0.030%. The AuZnO catalysts are robust and remain active after repeated laser exposure and cycling. The light intensity required to initiate CO{sub 2} reduction is low (#1;~2.5 x#4; 10{sup 5} W m{sup #5;-2}) and achievable with solar concentrators. Our results illustrate the viability of plasmonic heating approaches for CO{sub 2} utilization and other practical thermal catalytic applications.

  2. THE 0.8-14.5 {mu}m SPECTRA OF MID-L TO MID-T DWARFS: DIAGNOSTICS OF EFFECTIVE TEMPERATURE, GRAIN SEDIMENTATION, GAS TRANSPORT, AND SURFACE GRAVITY

    SciTech Connect (OSTI)

    Stephens, D. C.; Leggett, S. K.; Geballe, T. R.; Cushing, Michael C.; Marley, Mark S.; Saumon, D.; Golimowski, David A.; Noll, K. S.; Fan Xiaohui

    2009-09-01

    We present new 5.2-14.5 {mu}m low-resolution spectra of 14 mid-L to mid-T dwarfs. We also present new 3.0-4.1 {mu}m spectra for five of these dwarfs. These data are supplemented by existing red and near-infrared spectra ({approx}0.6-2.5 {mu}m), as well as red through mid-infrared spectroscopy of seven other L and T dwarfs presented by Cushing et al. We compare these spectra to those generated from the model atmospheres of Saumon and Marley. The models reproduce the observed spectra well, except in the case of one very red L3.5 dwarf, 2MASS J22244381-0158521. The broad wavelength coverage allows us to constrain almost independently the four parameters used to describe these photospheres in our models: effective temperature (T {sub eff}), surface gravity, grain sedimentation efficiency (f{sub sed}), and vertical gas transport efficiency (K{sub zz} ). The CH{sub 4} bands centered at 2.2, 3.3, and 7.65 {mu}m and the CO band at 2.3 {mu}m are sensitive to K{sub zz} , and indicates that chemical mixing is important in all L and T dwarf atmospheres. The sample of L3.5 to T5.5 dwarfs spans the range 1800 K{approx}> T{sub eff} {approx}>1000 K, with an L-T transition (spectral types L7 to T4) that lies between 1400 and 1100 K for dwarfs with typical near-infrared colors; bluer and redder dwarfs can be 100 K warmer or cooler, respectively, when using infrared spectral types. When using optical spectral types, the bluer dwarfs have more typical T {sub eff} values as they tend to have earlier optical spectral types. In this model analysis, f {sub sed} increases rapidly between types T0 and T4, indicating that increased sedimentation can explain the rapid disappearance of clouds at this stage of brown dwarf evolution. There is a suggestion that the transition to dust-free atmospheres happens at lower temperatures for lower gravity dwarfs.

  3. MAKE SUPER-EARTHS, NOT JUPITERS: ACCRETING NEBULAR GAS ONTO SOLID CORES AT 0.1AU AND BEYOND

    SciTech Connect (OSTI)

    Lee, Eve J.; Chiang, Eugene; Ormel, Chris W. E-mail: echiang@astro.berkeley.edu

    2014-12-20

    Close-in super-Earths having radii 1-4 R {sub ?} may possess hydrogen atmospheres comprising a few percent by mass of their rocky cores. We determine the conditions under which such atmospheres can be accreted by cores from their parent circumstellar disks. Accretion from the nebula is problematic because it is too efficient: we find that 10 M {sub ?} cores embedded in solar metallicity disks tend to undergo runaway gas accretion and explode into Jupiters, irrespective of orbital location. The threat of runaway is especially dire at ?0.1AU, where solids may coagulate on timescales orders of magnitude shorter than gas clearing times; thus nascent atmospheres on close-in orbits are unlikely to be supported against collapse by planetesimal accretion. The time to runaway accretion is well approximated by the cooling time of the atmosphere's innermost convective zone, whose extent is controlled by where H{sub 2} dissociates. Insofar as the temperatures characterizing H{sub 2} dissociation are universal, timescales for core instability tend not to vary with orbital distanceand to be alarmingly short for 10 M {sub ?} cores. Nevertheless, in the thicket of parameter space, we identify two scenarios, not mutually exclusive, that can reproduce the preponderance of percent-by-mass atmospheres for super-Earths at ?0.1AU, while still ensuring the formation of Jupiters at ? 1AU. Scenario (a): planets form in disks with dust-to-gas ratios that range from ?20 solar at 0.1AU to ?2 solar at 5AU. Scenario (b): the final assembly of super-Earth cores from mergers of proto-coresa process that completes quickly at ?0.1AU once begunis delayed by gas dynamical friction until just before disk gas dissipates completely. Both scenarios predict that the occurrence rate for super-Earths versus orbital distance, and the corresponding rate for Jupiters, should trend in opposite directions, as the former population is transformed into the latter: as gas giants become more frequent from ?1 to 10AU, super-Earths should become more rare.

  4. Nanoscale Au-In alloy-oxide core-shell particles as electrocatalysts for efficient hydroquinone detection

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Sutter, E.; Tong, X.; Medina-Plaza, C.; Rodriguez-Mendez, M. L.; Sutter, P.

    2015-10-09

    The presence of hydroquinone (HQ), a phenol ubiquitous in nature and widely used in industry, needs to be monitored because of its toxicity to the environment. Here we demonstrate efficient detection of HQ using simple, fast, and noninvasive electrochemical measurements on indium tin oxide (ITO) electrodes modified with nanoparticles comprising bimetallic Au–In cores and mixed Au–In oxide shells. Whereas bare ITO electrodes show very low activity for the detection of HQ, their modification with Au–In core–shell nanoparticles induces a pronounced shift of the oxidation peak to lower potentials, i.e., facilitated oxidation. The response of the different electrodes was correlated withmore » the initial composition of the bimetallic nanoparticle cores, which in turn determined the amount of Au and In stabilized on the surface of the amorphous Au–In oxide shells available for the electrochemical reaction. While adding core–shell nanostructures with different compositions of the alloy core facilitates the electrocatalytic (reduction-) oxidation of HQ, the activity is highest for particles with AuIn cores (i.e., a Au:In ratio of 1). This optimal system is found to follow a single pathway, the two-electron oxidation of the quinone–hydroquinone couple, which gives rise to high oxidation peaks and is most effective in facilitating the electrode-to-analyte charge transfer and thus detection. The limits of detection (LOD) decreased when increasing the amount of Au exposed on the surface of the amorphous Au–In oxide shells. As a result the LODs were in the range of 10–5 – 10–6 M and were lower than those obtained using bulk Au.« less

  5. Nanoscale Au-In alloy-oxide core-shell particles as electrocatalysts for efficient hydroquinone detection

    SciTech Connect (OSTI)

    Sutter, E.; Tong, X.; Medina-Plaza, C.; Rodriguez-Mendez, M. L.; Sutter, P.

    2015-10-09

    The presence of hydroquinone (HQ), a phenol ubiquitous in nature and widely used in industry, needs to be monitored because of its toxicity to the environment. Here we demonstrate efficient detection of HQ using simple, fast, and noninvasive electrochemical measurements on indium tin oxide (ITO) electrodes modified with nanoparticles comprising bimetallic Au–In cores and mixed Au–In oxide shells. Whereas bare ITO electrodes show very low activity for the detection of HQ, their modification with Au–In core–shell nanoparticles induces a pronounced shift of the oxidation peak to lower potentials, i.e., facilitated oxidation. The response of the different electrodes was correlated with the initial composition of the bimetallic nanoparticle cores, which in turn determined the amount of Au and In stabilized on the surface of the amorphous Au–In oxide shells available for the electrochemical reaction. While adding core–shell nanostructures with different compositions of the alloy core facilitates the electrocatalytic (reduction-) oxidation of HQ, the activity is highest for particles with AuIn cores (i.e., a Au:In ratio of 1). This optimal system is found to follow a single pathway, the two-electron oxidation of the quinone–hydroquinone couple, which gives rise to high oxidation peaks and is most effective in facilitating the electrode-to-analyte charge transfer and thus detection. The limits of detection (LOD) decreased when increasing the amount of Au exposed on the surface of the amorphous Au–In oxide shells. As a result the LODs were in the range of 10–5 – 10–6 M and were lower than those obtained using bulk Au.

  6. Thermoelectric Properties of Au- Containing Type-I Clathrates Ba8AuxGa16-3xGe30+2x

    SciTech Connect (OSTI)

    Ye, Zuxin; Cho, Jung Young; Tessema, Misle M.; Salvador, James R.; Waldo, Richard A.; Yang, Jihui; Wang, Hsin; Cai, Wei; Kirkham, Melanie J; Yang, Jiong; Zhang, Wenqing

    2014-01-01

    Type I clathrates, with compositions based on Ba8Ga16Ge30, are a class of promising thermoelectric materials due to their intrinsically low thermal conductivity. It has been demonstrated previously that the thermoelectric performance can be improved by transition metal substitution of the framework atoms. In this study, the effects of Au substitution for Ga/Ge on thermal and electrical transport properties of type I clathrate compounds have been investigated. Polycrystalline samples with a large range of Au content have been synthesized using conventional solid state techniques with the actual compositions of resulting materials approximately following Zintl-Klemm rules. The charge carrier type changes from electrons (n) to holes (p) as the Au content increases. The Seebeck coefficient (S) and power factor (S2/ where is the electrical resistivity) were improved by Au substitution and the resulting overall thermoelectric properties were enhanced by Au substitution with a thermoelectric figure of merit ZT ~ 0.63 at temperature T = 740 K for the composition Ba8Au5.47Ge39.96. The results presented herein show that Au-containing type I clathrates are promising p-type thermoelectric materials for high temperature applications.

  7. Nanochannel-Directed Growth of One-Dimensional Multi-Segment Heterojunctions of Metallic Au1-xGex and Semiconducting Ge

    SciTech Connect (OSTI)

    Li, Xiangdong; Meng, Guowen; Qin, Shengyong; Xu, Qiaoling; Chu, Zhaoqin; Zhu, Xiaoguang; Kong, Mingguang; Li, An-Ping

    2012-01-01

    We report on the synthesis of multi-segment nanowire (NW) junctions of Au{sub 1-x}Ge{sub x} and Ge inside the nanochannels of porous anodic aluminum oxide template. The one-dimensional heterostructures are grown with a low-temperature chemical vapor deposition process, assisted by electrodeposited Au nanowires (AuNWs). The Au-catalyzed vapor-liquid-solid growth process occurs simultaneously in multiple locations along the nanochannel, which leads to multi-segment Au{sub 1-x}Ge{sub x}/Ge heterojunctions. The structures of the as-grown hybrid NWs, analyzed by using transmission electron microscopy and energy-dispersive X-ray spectroscopy elemental mapping, show clear compositional modulation with variable modulation period and controllable junction numbers. Remarkably, both GeNW and Au{sub 1-x}Ge{sub x}NW segments are single crystalline with abrupt interfaces and good crystallographic coherences. The electronic and transport properties of individual NW junctions are measured by using a multi-probe scanning tunneling microscope, which confirms the semiconducting nature of Ge segments and the metallic behavior of Au{sub 1-x}Ge{sub x} segments, respectively. The high yield of multiple segment NW junctions of a metal-semiconductor can facilitate the applications in nanoelectronics and optoelectronics that harness multiple functionalities of heterointerfaces.

  8. Two-dimensional [sup 1]H-NMR EXSY study of the fluxional behavior of the novel carbenium ion complex [FvMo[sub 2](CO)[sub 4]([mu],[eta][sup 2],[eta][sup 3]-MeC[equivalent to]CCH[sub 2])][BF[sub 4

    SciTech Connect (OSTI)

    Amouri, H.E.; Besace, Y.; Vollhardt, K.P.C.; Ball, G.E. Lawrence Berkeley Lab., CA ); Vaissermann, J. )

    1993-03-01

    The title compound [FuMo[sub 2](CO)[sub 4]([mu],[eta][sup 2],[eta][sup 3]-MeC[equivalent to]CCH[sub 2])][BF[sub 4

  9. Effect of microwave irradiation on the resistance of Au-TiB{sub x}-Ge-Au-n-n{sup +}-n{sup ++}-GaAs(InP) ohmic contacts

    SciTech Connect (OSTI)

    Belyaev, A. E.; Sachenko, A. V.; Boltovets, N. S. Ivanov, V. N.; Konakova, R. V. Kudryk, Ya. Ya.; Matveeva, L. A.; Milenin, V. V.; Novitskii, S. V.; Sheremet, V. N.

    2012-04-15

    Temperature dependences of the contact resistivity {rho}{sub c} of Au-TiB{sub x}-Ge-Au-n-n{sup +}-n{sup ++}(GaAs)-InP ohmic contacts before and after short-term (10 s) microwave treatment have been studied both experimentally and theoretically. It is shown that {rho}{sub c} can decrease after microwave treatment in the entire temperature range of {rho}{sub c} measurements (100-400 K). Good agreement between the theoretical and experimental {rho}{sub c}(T) curves is attained and interpreted on the assumption that the dislocation density in the semiconductor near-surface region is varied as a result of microwave radiation.

  10. Significant in-medium {eta}{sup '} mass reduction in {radical}(s{sub NN}) = 200 GeV Au+Au collisions at the BNL Relativistic Heavy Ion Collider

    SciTech Connect (OSTI)

    Vertesi, R.; Sziklai, J.; Csoergo, T.

    2011-05-15

    In high-energy heavy ion collisions a hot and dense medium is formed, where the U{sub A}(1) or chiral symmetry may temporarily be restored. As a consequence, the mass of the {eta}{sup '}(958) mesons may be reduced to its quark model value, and the abundance of {eta}{sup '} mesons at low p{sub T} may be enhanced by more than a factor of 10. The intercept parameter {lambda}{sub *} of the charged pion Bose Einstein correlations provides a sensitive observable of the possibly enhanced {eta}{sup '} abundance. We have analyzed {lambda}{sub *}(m{sub T}) data from {radical}(s{sub N{sub N}})=200 GeV central Au+Au reactions measured at the BNL Relativistic Heavy Ion Collider (RHIC), using extensive Monte Carlo simulations based on six popular models for hadronic multiplicities. Based on the combined STAR and PHENIX data set, and on various systematic investigations of resonance multiplicities and model parameters, we conclude that in {radical}(s{sub N{sub N}})=200 GeV central Au+Au reactions the mass of the {eta}{sup '} meson is reduced by {Delta}m{sub {eta}}{sup '*}>200 MeV, at the 99.9% confidence level in the considered model class. Such a significant {eta}{sup '} mass modification may indicate the restoration of the U{sub A}(1) symmetry in a hot and dense hadronic matter and the return of the ninth ''prodigal'' Goldstone boson. A similar analysis of NA44 S+Pb data at top CERN Super Proton Synchroton (SPS) energies showed no significant in-medium {eta}{sup '} mass modification.

  11. Use of layer strains in strained-layer superlattices to make devices for operation in new wavelength ranges, E. G. , InAsSb at 8 to 12. mu. m. [InAs/sub 1-x/Sb/sub x/

    DOE Patents [OSTI]

    Osbourn, G.C.

    1983-10-06

    An intrinsic semiconductor electro-optical device comprises a p-n junction intrinsically responsive, when cooled, to electromagnetic radiation in the wavelength range of 8 to 12 ..mu..m. This radiation responsive p-n junction comprises a strained-layer superlattice (SLS) of alternating layers of two different III-V semiconductors. The lattice constants of the two semiconductors are mismatched, whereby a total strain is imposed on each pair of alternating semiconductor layers in the SLS structure, the proportion of the total strain which acts on each layer of the pair being proportional to the ratio of the layer thicknesses of each layer in the pair.

  12. Electronic structure and conductivity of nanocomposite metal (Au,Ag,Cu,Mo)-containing amorphous carbon films

    SciTech Connect (OSTI)

    Endrino, Jose L.; Horwat, David; Gago, Raul; Andersson, Joakim; Liu, Y.S.; Guo, Jinghua; Anders, Andre

    2008-05-14

    In this work, we study the influence of the incorporation of different metals (Me = Au, Ag, Cu, Mo) on the electronic structure of amorphous carbon (a-C:Me) films. The films were produced at room temperature using a novel pulsed dual-cathode arc deposition technique. Compositional analysis was performed with secondary neutral mass spectroscopy whereas X-ray diffraction was used to identify the formation of metal nanoclusters in the carbon matrix. The metal content incorporated in the nanocomposite films induces a drastic increase in the conductivity, in parallel with a decrease in the band gap corrected from Urbach energy. The electronic structure as a function of the Me content has been monitored by x-ray absorption near edge structure (XANES) at the C K-edge. XANES showed that the C host matrix has a dominant graphitic character and that it is not affected significantly by the incorporation of metal impurities, except for the case of Mo, where the modifications in the lineshape spectra indicated the formation of a carbide phase. Subtle modifications of the spectral lineshape are discussed in terms of nanocomposite formation.

  13. Understanding the Kondo resonance in the d-CoPc/Au(111) adsorption system

    SciTech Connect (OSTI)

    Wang, Yu; Zheng, Xiao Li, Bin; Yang, Jinlong

    2014-08-28

    By combining the density functional theory (DFT) and a hierarchical equations of motion (HEOM) approach, we investigate the Kondo phenomena in a composite system consisting of a dehydrogenated cobalt phthalocyanine molecule (d-CoPc) adsorbed on an Au(111) surface. DFT calculations are performed to determine the ground-state geometric and electronic structures of the adsorption system. It is found that the singly occupied d{sub z{sup 2}} orbital of Co forms a localized spin, which could be screened by the substrate conduction electrons. This screening leads to the prominent Kondo features as observed in the scanning tunneling microscopy experiments. We then employ the HEOM approach to characterize the Kondo correlations of the adsorption system. The calculated temperature-dependent differential conductance spectra and the predicted Kondo temperature agree well with the experiments, and the universal Kondo scaling behavior is correctly reproduced. This work thus provides important insights into the relevant experiments, and it also highlights the applicability of the combined DFT+HEOM approach to the studies of strongly correlated condensed matter systems.

  14. Six-dimensional quantum dynamics study for the dissociative adsorption of DCl on Au(111) surface

    SciTech Connect (OSTI)

    Liu, Tianhui; Fu, Bina, E-mail: bina@dicp.ac.cn, E-mail: zhangdh@dicp.ac.cn; Zhang, Dong H., E-mail: bina@dicp.ac.cn, E-mail: zhangdh@dicp.ac.cn [State Key Laboratory of Molecular Reaction Dynamics and Center for Theoretical Computational Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China)

    2014-04-14

    We carried out six-dimensional quantum dynamics calculations for the dissociative adsorption of deuterium chloride (DCl) on Au(111) surface using the initial state-selected time-dependent wave packet approach. The four-dimensional dissociation probabilities are also obtained with the center of mass of DCl fixed at various sites. These calculations were all performed based on an accurate potential energy surface recently constructed by neural network fitting to density function theory energy points. The origin of the extremely small dissociation probability for DCl/HCl (v=0, j=0) fixed at the top site compared to other fixed sites is elucidated in this study. The influence of vibrational excitation and rotational orientation of DCl on the reactivity was investigated by calculating six-dimensional dissociation probabilities. The vibrational excitation of DCl enhances the reactivity substantially and the helicopter orientation yields higher dissociation probability than the cartwheel orientation. The site-averaged dissociation probability over 25 fixed sites obtained from four-dimensional quantum dynamics calculations can accurately reproduce the six-dimensional dissociation probability.

  15. Surface plasmon dispersion engineering via double-metallic AU/AG layers for nitride light-emitting diodes

    DOE Patents [OSTI]

    Tansu, Nelson; Zhao, Hongping; Zhang, Jing; Liu, Guangyu

    2014-04-01

    A double-metallic deposition process is used whereby adjacent layers of different metals are deposited on a substrate. The surface plasmon frequency of a base layer of a first metal is tuned by the surface plasmon frequency of a second layer of a second metal formed thereon. The amount of tuning is dependent upon the thickness of the metallic layers, and thus tuning can be achieved by varying the thicknesses of one or both of the metallic layers. In a preferred embodiment directed to enhanced LED technology in the green spectrum regime, a double-metallic Au/Ag layer comprising a base layer of gold (Au) followed by a second layer of silver (Ag) formed thereon is deposited on top of InGaN/GaN quantum wells (QWs) on a sapphire/GaN substrate.

  16. Self-organization of S adatoms on Au(111): √3R30° rows at low coverage

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Walen, Holly; Liu, Da -Jiang; Oh, Junepyo; Lim, Hyunseob; Evans, J. W.; Kim, Yousoo; Thiel, P. A.

    2015-07-06

    Using scanning tunneling microscopy, we observe an adlayer structure that is dominated by short rows of S atoms, on unreconstructed regions of a Au(111) surface. This structure forms upon adsorption of low S coverage (less than 0.1 monolayer) on a fully reconstructed cleansurface at 300 K, then cooling to 5 K for observation. The rows adopt one of three orientations that are rotated by 30° from the close-packed directions of the Au(111) substrate, and adjacent S atoms in the rows are separated by √3 times the surface lattice constant, a. Monte Carlo simulations are performed on lattice-gas models, we derivedmore » using a limited cluster expansion based on density functional theory energetics. Furthermore, models which include long-range pairwise interactions (extending to 5a), plus selected trio interactions, successfully reproduce the linear rows of S atoms at reasonable temperatures.« less

  17. Magnetic switching behaviors of orbital states with different magnetic quantum numbers in Au/Fe/MgO multilayer system

    SciTech Connect (OSTI)

    Suzuki, Kosuke Takubo, Shota; Kato, Tadashi; Yamazoe, Masatoshi; Hoshi, Kazushi; Sakurai, Hiroshi; Homma, Yoshiya; Itou, Masayoshi; Sakurai, Yoshiharu

    2014-08-18

    A spin specific magnetic hysteresis (SSMH) curve and an orbital specific magnetic hysteresis (OSMH) curve are obtained for Fe/Au/Fe/MgO multilayers by magnetic Compton scattering and SQUID magnetometer measurements. The SSMH curve with each contribution of magnetic quantum number |m| = 0, 1, and 2 states is obtained by decomposition analyses of magnetic Compton profiles. Residual magnetization is observed for the SSMH curve with magnetic quantum number |m| = 0, 2 and the OSMH curve. Although the SQUID magnetometer measurements do not show perpendicular magnetic anisotropy (PMA) in the present Fe/Au/Fe/MgO multilayer film, the SSMH curve with magnetic quantum number |m| = 0, 2 and OSMH curve show switching behaviors of PMA.

  18. Conductance and spin-filter effects of oxygen-incorporated Au, Cu, and Fe single-atom chains

    SciTech Connect (OSTI)

    Zheng, Xiaolong; Xie, Yi-Qun Ye, Xiang; Ke, San-Huang

    2015-01-28

    We studied the spin-polarized electron transport in oxygen-incorporated Au, Cu, and Fe single-atom chains (SACs) by first-principles calculations. We first investigated the mechanism responsible for the low conductance (<1G{sub 0}) of the Au and Cu SACs in an oxygen environment reported in recent experiments. We found that for the Au SACs, the low conductance plateau around 0.6G{sub 0} can be attributed to a distorted chain doped with a single oxygen atom, while the 0.1G{sub 0} conductance comes from a linear chain incorporated with an oxygen molecule and is caused by an antibonding state formed by oxygen's occupied frontier orbital with d{sub z} orbitals of adjacent Au atoms. For the Cu SACs, the conductance about 0.3G{sub 0} is ascribed to a special configuration that contains Cu and O atoms in an alternating sequence. This exhibits an even-odd conductance oscillation with an amplitude of ∼0.1G{sub 0}. In contrast, for the alternating Fe-O SACs, conductance overall decreases with an increase in O atoms and it approaches nearly zero for the chain with more than four O atoms. While the Cu-O SACs behave as perfect spin filters for one spin channel due to the half metallic nature, the Fe-O SACs can serve as perfect spin filters for two spin channels depending on the polarity of the applied gate voltage.

  19. Φ meson production in d+Au collisions at √sNN = 200 GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adare, A.

    2015-10-19

    The PHENIX Collaboration has measured Φ meson production in d+Au collisions at √sNN=200 GeV using the dimuon and dielectron decay channels. The Φ meson is measured in the forward (backward) d-going (Au-going) direction, 1.2 < y < 2.2 (–2.2 < y < –1.2) in the transverse-momentum (pT) range from 1–7 GeV/c and at midrapidity |y|<0.35 in the pT range below 7 GeV/c. The Φ meson invariant yields and nuclear-modification factors as a function of pT, rapidity, and centrality are reported. An enhancement of Φ meson production is observed in the Au-going direction, while suppression is seen in the d-going direction,more » and no modification is observed at midrapidity relative to the yield in p+p collisions scaled by the number of binary collisions. As a result, similar behavior was previously observed for inclusive charged hadrons and open heavy flavor, indicating similar cold-nuclear-matter effects.« less

  20. Φ meson production in d+Au collisions at √sNN = 200 GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adare, A.

    2015-10-19

    The PHENIX Collaboration has measured Φ meson production in d+Au collisions at √sNN=200 GeV using the dimuon and dielectron decay channels. The Φ meson is measured in the forward (backward) d-going (Au-going) direction, 1.2 T) range from 1–7 GeV/c and at midrapidity |y|T range below 7 GeV/c. The Φ meson invariant yields and nuclear-modification factors as a function of pT, rapidity, and centrality are reported. An enhancement of Φ meson production is observed in the Au-going direction, while suppression is seen in the d-going direction,more »and no modification is observed at midrapidity relative to the yield in p+p collisions scaled by the number of binary collisions. As a result, similar behavior was previously observed for inclusive charged hadrons and open heavy flavor, indicating similar cold-nuclear-matter effects.« less

  1. Φ meson production in d+Au collisions at √sNN = 200 GeV

    SciTech Connect (OSTI)

    Adare, A.

    2015-10-19

    The PHENIX Collaboration has measured Φ meson production in d+Au collisions at √sNN=200 GeV using the dimuon and dielectron decay channels. The Φ meson is measured in the forward (backward) d-going (Au-going) direction, 1.2 < y < 2.2 (–2.2 < y < –1.2) in the transverse-momentum (pT) range from 1–7 GeV/c and at midrapidity |y|<0.35 in the pT range below 7 GeV/c. The Φ meson invariant yields and nuclear-modification factors as a function of pT, rapidity, and centrality are reported. An enhancement of Φ meson production is observed in the Au-going direction, while suppression is seen in the d-going direction, and no modification is observed at midrapidity relative to the yield in p+p collisions scaled by the number of binary collisions. As a result, similar behavior was previously observed for inclusive charged hadrons and open heavy flavor, indicating similar cold-nuclear-matter effects.

  2. The effects of fabrication and annealing on the structure and hydrogen permeation of Pd-Au binary alloy membranes

    SciTech Connect (OSTI)

    Gade, Sabina K; Payzant, E Andrew; Park, Helen J; Thoen, Paul M; Way, J. Douglas

    2009-01-01

    The addition of gold to palladium membranes produces many desirable effects for hydrogen purification, including improved tolerance of sulfur compounds, reduction in hydride phase formation, and, for certain compositions, improved hydrogen permeability. The focus of this work is to determine if sequential plating can be used to produce self-supported alloy membranes with equivalent properties to membranes produced by conventional metallurgical techniques such as cold-working. Sequential electroplating and electroless plating were used to produce freestanding planar Pd-Au membranes with Au contents ranging from 0 to 20 wt%, consisting of Au layers on both sides of a pure Pd core. Membranes were characterized by single-gas permeation measurements, scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDS), and high temperature, controlled-atmosphere XRD (HTXRD). Sequentially plated foils tested without any prior annealing had significantly lower H2 permeabilities than either measured or literature values for homogeneous foils of equivalent composition. This effect appears to be due to the formation of stable gold-enriched surface layers. Pretreatment of membranes to 1023 K created membranes with hydrogen permeabilities equivalent to literature values, despite the fact that trace amounts of surface gold remained detectable with XRD.

  3. The effect of Au and Ni doping on the heavy fermion state of the Kondo lattice antiferromagnet CePtZn

    SciTech Connect (OSTI)

    Dhar, S. K.; Aoki, Y.; Suemitsu, B.; Miyazaki, R.; Provino, A.; Manfrinetti, P.

    2014-05-07

    We have probed the effect of doping CePtZn with Au and Ni and also investigated in detail the magnetic behavior of the iso-structural CeAuZn. A magnetic ground state is observed in both CePt{sub 0.9}Au{sub 0.1}Zn and CePt{sub 0.9}Ni{sub 0.1}Zn with T{sub N}?=?2.1 and 1.1?K and the coefficient of the linear term of electronic heat capacity ??=?0.34 and 0.9?J/mol K{sup 2}, respectively. The corresponding values for CePtZn are 1.7?K and 0.6?J/mol K{sup 2}. The altered values of T{sub N} and ? show that the electronic correlations in CePtZn are affected by doping with Au and Ni. CeAuZn orders magnetically near 1.7?K and its electrical resistivity shows a normal metallic behavior. Together with a ? of 0.022?J/mol K{sup 2} the data indicate a weak 4f-conduction electron hybridization in CeAuZn characteristic of normal trivalent cerium based systems.

  4. Exchange bias effect in Au-Fe3O4 dumbbell nanoparticles induced by the charge transfer from gold

    SciTech Connect (OSTI)

    Feygenson, Mikhail; Bauer, John C; Gai, Zheng; Marques, Carlos; Aronson, Meigan C.; Teng, Xiaowei; Su, Dong; Stanic, Vesna; Urban, Volker S; Kevin, Beyer; Dai, Sheng

    2015-08-10

    We have studied the origin of the exchange bias effect in the Au-Fe3O4 dumbbell nanoparticles in two samples with different sizes of the Au seed nanoparticles (4.1 and 2.7 nm) and same size of Fe3O4 nanoparticles (9.8 nm). The magnetization, small-angle neutron scattering, synchrotron x-ray diffraction and scanning transmission electron microscope measurements determined the antiferromagnetic FeO wstite phase within Fe3O4 nanoparticles, originating at the interface with the Au nanoparticles. The interface between antiferromagnetic FeO and ferrimagnetic Fe3O4 is giving rise to the exchange bias effect. The strength of the exchange bias fields depends on the interfacial area and lattice mismatch between both phases. We propose that the charge transfer from the Au nanoparticles is responsible for a partial reduction of the Fe3O4 into FeO phase at the interface with Au nanoparticles. The Au-O bonds are formed across the interface to accommodate an excess of oxygen released during the reduction of magnetite.

  5. Shape transformation of bimetallic Au–Pd core–shell nanocubes to multilayered Au–Pd–Au core–shell hexagonal platelets

    SciTech Connect (OSTI)

    Bhattarai, Nabraj; Prozorov, Tanya

    2015-11-05

    Transformation of metallic or bimetallic (BM) nanoparticles (NPs) from one shape to another desired shape is of importance to nanoscience and nanotechnology, where new morphologies of NPs lead to enhancement of their exploitable properties. In this report, we present the shape transformation of Au octahedral NPs to Au–Pd core–shell nanocubes, followed by their transformation to nanostars and finally to multilayered Au–Pd–Au core–shell hexagonal platelets in the presence of T30 DNA. The weaker binding affinity of T30 DNA directs the growth to favor the formation of lower energy {111} facets, changing the morphology from nanocubes to nanostar. The nanostars, exhibiting unusual intermediate morphologies, are comprised two sets of shell layers and have Au core, Pd intermediate shell, and Au outer shell. Similarly, the hexagonal platelets, which also have Au core and inner Pd shell, are encased in an external gold shell. As a result, the formation of multilayered Au–Pd–Au core–shell hexagonal platelets from Au–Pd core–shell nanocubes via the multilayered nanostars is monitored using scanning/transmission electron microscopy analysis.

  6. Shape transformation of bimetallic Au–Pd core–shell nanocubes to multilayered Au–Pd–Au core–shell hexagonal platelets

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Bhattarai, Nabraj; Prozorov, Tanya

    2015-11-05

    Transformation of metallic or bimetallic (BM) nanoparticles (NPs) from one shape to another desired shape is of importance to nanoscience and nanotechnology, where new morphologies of NPs lead to enhancement of their exploitable properties. In this report, we present the shape transformation of Au octahedral NPs to Au–Pd core–shell nanocubes, followed by their transformation to nanostars and finally to multilayered Au–Pd–Au core–shell hexagonal platelets in the presence of T30 DNA. The weaker binding affinity of T30 DNA directs the growth to favor the formation of lower energy {111} facets, changing the morphology from nanocubes to nanostar. The nanostars, exhibiting unusualmore » intermediate morphologies, are comprised two sets of shell layers and have Au core, Pd intermediate shell, and Au outer shell. Similarly, the hexagonal platelets, which also have Au core and inner Pd shell, are encased in an external gold shell. As a result, the formation of multilayered Au–Pd–Au core–shell hexagonal platelets from Au–Pd core–shell nanocubes via the multilayered nanostars is monitored using scanning/transmission electron microscopy analysis.« less

  7. Bond-bending isomerism of Au2I3-: Competition between covalent bonding and aurophilicity

    SciTech Connect (OSTI)

    Li, Wan -Lu; Liu, Hong -Tao; Jian, Tian; Lopez, Gary V.; Piazza, Zachary A.; Huang, Dao -Ling; Chen, Teng -Teng; Su, Jing; Yang, Ping; Chen, Xin; Wang, Lai -Sheng; Li, Jun

    2015-10-13

    We report a joint photoelectron spectroscopy and theoretical investigation of the gaseous Au2I3 cluster, which is found to exhibit two types of isomers due to competition between Au–I covalent bonding and Au–Au aurophilic interactions. The covalent bonding favors a bent IAuIAuI structure with an obtuse Au–I–Au angle (100.7°), while aurophilic interactions pull the two Au atoms much closer, leading to an acutely bent structure (72.0°) with an Au–Au distance of 3.08 Å. The two isomers are separated by a small barrier and are nearly degenerate with the obtuse isomer being slightly more stable. At low temperature, only the obtuse isomer is observed; distinct experimental evidence is observed for the co-existence of a combination of isomers with both acute and obtuse bending angles at room temperature. As a result, the two bond-bending isomers of Au2I3 reveal a unique example of one molecule being able to oscillate between different structures as a result of two competing chemical forces.

  8. IRS SCAN-MAPPING OF THE WASP-WAIST NEBULA (IRAS 16253-2429). I. DERIVATION OF SHOCK CONDITIONS FROM H{sub 2} EMISSION AND DISCOVERY OF 11.3 {mu}m PAH ABSORPTION

    SciTech Connect (OSTI)

    Barsony, Mary; Wolf-Chase, Grace A.; Ciardi, David R.

    2010-09-01

    The outflow driven by the Class 0 protostar, IRAS 16253-2429, is associated with bipolar cavities visible in scattered mid-infrared light, which we refer to as the Wasp-Waist Nebula. InfraRed Spectometer (IRS) scan mapping with the Spitzer Space Telescope of a {approx}1' x 2' area centered on the protostar was carried out. The outflow is imaged in six pure rotational (0-0 S(2) through 0-0 S(7)) H{sub 2} lines, revealing a distinct, S-shaped morphology in all maps. A source map in the 11.3 {mu}m polycyclic aromatic hydrocarbon (PAH) feature is presented in which the protostellar envelope appears in absorption. This is the first detection of absorption in the 11.3 {mu}m PAH feature. Spatially resolved excitation analysis of positions in the blue- and redshifted outflow lobes, with extinction-corrections determined from archival Spitzer 8 {mu}m imaging, shows remarkably constant temperatures of {approx}1000 K in the shocked gas. The radiated luminosity in the observed H{sub 2} transitions is found to be 1.94 {+-} 0.05 x 10{sup -5} L{sub sun} in the redshifted lobe and 1.86 {+-} 0.04 x 10{sup -5} L{sub sun} in the blueshifted lobe. These values are comparable to the mechanical luminosity of the flow. By contrast, the mass of hot (T {approx} 1000 K) H{sub 2} gas is 7.95 {+-} 0.19 x 10{sup -7} M{sub sun} in the redshifted lobe and 5.78 {+-} 0.17 x 10{sup -7} M{sub sun} in the blueshifted lobe. This is just a tiny fraction, of order 10{sup -3}, of the gas in the cold (30 K), swept-up gas mass derived from millimeter CO observations. The H{sub 2} ortho/para ratio of 3:1 found at all mapped points in this flow suggests previous passages of shocks through the gas. Comparison of the H{sub 2} data with detailed shock models of Wilgenbus et al. shows the emitting gas is passing through Jump (J-type) shocks. Pre-shock densities of 10{sup 4} cm{sup -3{<=}} n {sub H{<=}} 10{sup 5} cm{sup -3} are inferred for the redshifted lobe and n {sub H{<=}} 10{sup 3} cm{sup -3} for the blueshifted lobe. Shock velocities are 5 km s{sup -1} {<=} v{sub s} {<=} 10 km s{sup -1} for the redshifted gas and v{sub s} = 10 km s{sup -1} for the blueshifted gas. Initial transverse (to the shock) magnetic field strengths for the redshifted lobe are in the range 10-32 {mu}G, and just 3 {mu}G for the blueshifted lobe. A cookbook for using the CUBISM contributed software for IRS spectral mapping data is presented in the Appendix.

  9. PARTICLE ACCELERATION AT QUASI-PARALLEL SHOCK WAVES: THEORY AND OBSERVATIONS AT 1 AU

    SciTech Connect (OSTI)

    Neergaard Parker, L.; Zank, G. P.

    2012-09-20

    In this paper, we describe a theoretical model for accelerating an arbitrary upstream particle distribution. Only those particles that exceed a prescribed injection energy, E{sub inj}, are accelerated via the diffusive shock acceleration (DSA) mechanism, also known as first-order Fermi acceleration. We identify a set of quasi-parallel shocks at 1 AU and use the observed solar wind particle distribution information to construct our upstream distribution, which is then accelerated diffusively at the shock, assuming the observed shock parameters. The injection energy for particles to be accelerated diffusively at a quasi-parallel shock is discussed theoretically. By using the observed upstream solar wind distribution function and the observed shock parameters, we can compute the injection energy that matches the observed downstream accelerated particle spectrum. Like the previous studies of van Nes et al., Lario et al., and Ho et al., this analysis focuses on the acceleration of protons only via the first-order Fermi acceleration mechanism. However, our primary focus is on quasi-parallel shocks and the injection mechanism in the context of DSA with a background thermal solar wind modeled as a Maxwellian or kappa distribution. Our approach allows for a direct test of injection at interplanetary shocks. It has been proposed that an additional seed population of energetic particles is needed to explain the accelerated particle distribution downstream of quasi-parallel shocks. This conclusion is based typically on studies that address the acceleration of heavy ions primarily and do not characterize the injection of protons alone using the DSA mechanism. Through comparisons of Maxwellian and kappa upstream distributions, we find that DSA with injection directly from a thermal Maxwellian distribution, or weak departures therefrom, for protons is responsible for energetic solar particle events associated with quasi-parallel shocks.

  10. ELECTRON HEAT FLUX IN THE SOLAR WIND: ARE WE OBSERVING THE COLLISIONAL LIMIT IN THE 1 AU DATA?

    SciTech Connect (OSTI)

    Landi, S.; Matteini, L.; Pantellini, F.

    2014-07-20

    Using statistically significant data at 1AU, it has recently been shown (Bale et al.) that in the solar wind, when the Knudsen number K {sub T} (the ratio between the electron mean free path and the electron temperature scale height) drops below about 0.3, the electron heat flux q intensity rapidly approaches the classical collisional Spitzer-Hrm limit. Using a fully kinetic model including the effect of Coulomb collisions and the expansion of the solar wind with heliocentric distance, we observe that the heat flux strength does indeed approach the collisional value for Knudsen numbers smaller than about 0.3 in very good agreement with the observations. However, closer inspection of the heat flux properties, such as its variation with the heliocentric distance and its dependence on the plasma parameters, shows that for Knudsen numbers between 0.02 and 0.3 the heat flux is not conveniently described by the Spitzer-Hrm formula. We conclude that even though observations at 1 AU seem to indicate that the electron heat flux intensity approaches the collisional limit when the Knudsen drops below ?0.3, the collisional limit is not a generally valid closure for a Knudsen larger than 0.01. Moreover, the good agreement between the heat flux from our model and the heat flux from solar wind measurements in the high-Knudsen number regime seems to indicate that the heat flux at 1AU is not constrained by electromagnetic instabilities as both wave-particle and wave-wave interactions are neglected in our calculations.

  11. Structural characterization of metastable hcp-Ni thin films epitaxially grown on Au(100) single-crystal underlayers

    SciTech Connect (OSTI)

    Ohtake, Mitsuru; Tanaka, Takahiro; Futamoto, Masaaki; Kirino, Fumiyoshi

    2010-05-15

    Ni(1120) epitaxial thin films with hcp structure were prepared on Au(100) single-crystal underlayers at 100 deg. C by ultra high vacuum molecular beam epitaxy. The detailed film structure is studied by in situ reflection high energy electron diffraction, x-ray diffraction, and transmission electron microscopy. The hcp-Ni film consists of two types of variants whose c-axes are rotated around the film normal by 90 deg. each other. An atomically sharp boundary is recognized between the film and the underlayer, where misfit dislocations are introduced. Presence of such dislocations seems to relieve the strain caused by the lattice mismatch between the film and the underlayer.

  12. Temperature dependence of the photo-induced inverse spin Hall effect in Au/InP hybrid structures

    SciTech Connect (OSTI)

    Khamari, Shailesh K. Porwal, S.; Dixit, V. K.; Sharma, T. K.

    2014-01-27

    Photo-induced Inverse Spin Hall Effect (ISHE) measurements on Au/InP hybrid structures are performed over a temperature range of 45 to 300?K. Dependence of the spin current density on the degree of circular polarization and also on the angle of incidence of laser beam confirms the ISHE origin of measured signal. The magnitude of ISHE increases with sample cooling. A numerical model based on the spin relaxation of non-equilibrium spin-polarized electrons is proposed for predicting the temperature dependence of ISHE. Our results indicate that the proposed device can be used as a spin photodetector over a wide temperature range.

  13. INTERPLANETARY PROPAGATION OF SOLAR ENERGETIC PARTICLE HEAVY IONS OBSERVED AT 1 AU AND THE ROLE OF ENERGY SCALING

    SciTech Connect (OSTI)

    Mason, G. M.; Haggerty, D. K.; Li, G.; Zank, G. P.; Cohen, C. M. S.; Leske, R. A.; Mewaldt, R. A.; Desai, M. I.

    2012-12-20

    We have studied {approx}0.3 to >100 MeV nucleon{sup -1} H, He, O, and Fe in 17 large western hemisphere solar energetic particle events (SEP) to examine whether the often observed decrease of Fe/O during the rise phase is due to mixing of separate SEP particle populations, or is an interplanetary transport effect. Our earlier study showed that the decrease in Fe/O nearly disappeared if Fe and O were compared at energies where the two species interplanetary diffusion coefficient were equal, and therefore their kinetic energy nucleon{sup -1} was different by typically a factor {approx}2 ({sup e}nergy scaling{sup )}. Using an interplanetary transport model that includes effects of focusing, convection, adiabatic deceleration, and pitch angle scattering we have fit the particle spectral forms and intensity profiles over a broad range of conditions where the 1 AU intensities were reasonably well connected to the source and not obviously dominated by local shock effects. The transport parameters we derive are similar to earlier studies. Our model follows individual particles with a Monte Carlo calculation, making it possible to determine many properties and effects of the transport. We find that the energy scaling feature is preserved, and that the model is reasonably successful at fitting the magnitude and duration of the Fe/O ratio decrease. This along with successfully fitting the observed decrease of the O/He ratio leads us to conclude that this feature is best understood as a transport effect. Although the effects of transport, in particular adiabatic deceleration, are very significant below a few MeV nucleon{sup -1}, the spectral break observed in these events at 1 AU is only somewhat modified by transport, and so the commonly observed spectral breaks must be present at injection. For scattering mean free paths of the order of 0.1 AU adiabatic deceleration is so large below {approx}200 keV nucleon{sup -1} that ions starting with such energies at injection are cooled sufficiently as to be unobservable at 1 AU. Because of the complicating factors of different spectral break energies for different elements, it appears that SEP abundances determined below the break are least susceptible to systematic distortions.

  14. THE SOLAR NEIGHBORHOOD. XXV. DISCOVERY OF NEW PROPER MOTION STARS WITH 0.''40 yr{sup -1} > {mu} {>=} 0.''18 yr{sup -1} BETWEEN DECLINATIONS -47{sup 0} AND 00{sup 0}

    SciTech Connect (OSTI)

    Boyd, Mark R.; Winters, Jennifer G.; Henry, Todd J.; Jao, Wei-Chun; Finch, Charlie T.; Subasavage, John P.; Hambly, Nigel C. E-mail: winters@chara.gsu.edu E-mail: jao@chara.gsu.edu E-mail: jsubasavage@ctio.noao.edu

    2011-07-15

    We present 2817 new southern proper motion systems with 0.''40 yr{sup -1} > {mu} {>=} 0.''18 yr{sup -1} and declination between -47{sup 0} and 00{sup 0}. This is a continuation of the SuperCOSMOS-RECONS (SCR) proper motion searches of the southern sky. We use the same photometric relations as previous searches to provide distance estimates based on the assumption that the objects are single main-sequence stars. We find 79 new red dwarf systems predicted to be within 25 pc, including a few new components of previously known systems. Two systems-SCR 1731-2452 at 9.5 pc and SCR 1746-3214 at 9.9 pc-are anticipated to be within 10 pc. We also find 23 new white dwarf (WD) candidates with distance estimates of 15-66 pc, as well as 360 new red subdwarf candidates. With this search, we complete the SCR sweep of the southern sky for stars with {mu} {>=} 0.''18 yr{sup -1} and R{sub 59F} {<=} 16.5, resulting in a total of 5042 objects in 4724 previously unreported proper motion systems. Here we provide selected comprehensive lists from our SCR proper motion search to date, including 152 red dwarf systems estimated to be within 25 pc (9 within 10 pc), 46 WDs (10 within 25 pc), and 598 subdwarf candidates. The results of this search suggest that there are more nearby systems to be found at fainter magnitudes and lower proper motion limits than those probed so far.

  15. Centrality-dependent direct photon p{sub t} spectra in Au+Au collisions at the BNL Relativistic Heavy Ion Collider (RHIC) energy {radical}(s{sub NN})=200 GeV

    SciTech Connect (OSTI)

    Liu Fuming; Zhu Yan; Hirano, Tetsufumi; Werner, Klaus

    2009-01-15

    We calculate the centrality dependence of transverse momentum (p{sub t}) spectra for direct photons in Au+Au collisions at the BNL Relativistic Heavy Ion Collider (RHIC) energy {radical}(s{sub NN})=200 GeV, based on a realistic data-constrained (3+1)-dimensional hydrodynamic description of the expanding hot and dense matter, a reasonable treatment of the propagation of partons and their energy loss in the fluid, and a systematic study of the main sources of direct photons. The resultant p{sub t} spectra agree with recent PHENIX data in a broad p{sub t} range. The competition among the different direct photon sources is investigated at various centralities. Parton energy loss in the plasma is considered for photons from fragmentation and jet-photon conversion, which causes about 40% decrease in the total contribution. In the high p{sub t} region, the observed R{sub AA} of photons is centrality independent at the accuracy of 5% based on a realistic treatment of energy loss. We also link the different behavior of R{sub AA} for central and peripheral collisions, in the low p{sub t} region, to the fact that the plasma in central collisions is hotter than that in peripheral ones.

  16. Determination of redox reaction rates and orders by in situ liquid cell electron microscopy of Pd and Au solution growth

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Sutter, Eli A.; Sutter, Peter W.

    2014-11-19

    In-situ liquid cell transmission and scanning transmission electron microscopy (TEM/STEM) experiments are important as they provide direct insight into processes in liquids, such as solution growth of nanoparticles among others. In liquid cell TEM/STEM redox reaction experiments the hydrated electrons e⁻aq created by the electron beam are responsible for the reduction of metal-ion complexes. Here we investigate the rate equation of redox reactions involving reduction by e⁻aq generated by the electron beam during in-situ liquid TEM/STEM. Specifically we consider the growth of Pd on Au seeds in aqueous solutions containing Pd-chloro complexes. From the quantification of the rate of Pdmore » deposition at different electron beam currents and as a function of distance from a stationary, nanometer-sized exciting beam, we determine that the reaction is first order with respect to the concentration of hydrated electrons, [e⁻aq]. In addition, by comparing Pd- and Au-deposition, we further demonstrate that measurements of the local deposition rate on nanoparticles in the solution via real-time imaging can be used to measure not only [e⁻aq] but also the rate of reduction of a metal-ion complex to zero-valent metal atoms in solution.« less

  17. Determination of redox reaction rates and orders by in situ liquid cell electron microscopy of Pd and Au solution growth

    SciTech Connect (OSTI)

    Sutter, Eli A.; Sutter, Peter W.

    2014-11-19

    In-situ liquid cell transmission and scanning transmission electron microscopy (TEM/STEM) experiments are important as they provide direct insight into processes in liquids, such as solution growth of nanoparticles among others. In liquid cell TEM/STEM redox reaction experiments the hydrated electrons e?aq created by the electron beam are responsible for the reduction of metal-ion complexes. Here we investigate the rate equation of redox reactions involving reduction by e?aq generated by the electron beam during in-situ liquid TEM/STEM. Specifically we consider the growth of Pd on Au seeds in aqueous solutions containing Pd-chloro complexes. From the quantification of the rate of Pd deposition at different electron beam currents and as a function of distance from a stationary, nanometer-sized exciting beam, we determine that the reaction is first order with respect to the concentration of hydrated electrons, [e?aq]. In addition, by comparing Pd- and Au-deposition, we further demonstrate that measurements of the local deposition rate on nanoparticles in the solution via real-time imaging can be used to measure not only [e?aq] but also the rate of reduction of a metal-ion complex to zero-valent metal atoms in solution.

  18. Structural Changes in Self-Catalyzed Adsorption of Carbon Monoxide on 1,4-Phenylene Diisocyanide Modified Au(111)

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kestell, John; Boscoboinik, J. Anibal; Cheng, Lanxia; Garvey, Michael; Bennett, Dennis W.; Tysoe, Wilfred T.

    2015-07-23

    The self-accelerated adsorption of CO on 1,4-phenylene diisocyanide (PDI)-derived oligomers on Au(111) is explored by reflection–absorption infrared spectroscopy and scanning tunneling microscopy. PDI incorporates gold adatoms from the Au(111) surface to form one-dimensional —(Au–PDI)n— chains that can also connect between gold nanoparticles on mica to form a conductive pathway between them. CO adsorption occurs in two stages; it first adsorbs adjacent to the oligomers that move to optimize CO adsorption. Further CO exposure induces PDI decoordination to form Au–PDI adatom complexes thereby causing the conductivity of a PDI-linked gold nanoparticle array on mica to decrease to act as a chemicallymore » drive molecular switch. This simple system enables the adsorption process to be explored in detail. DFT calculations reveal that both the —(Au–PDI)n— oligomer chain and the Au–PDI adatom complex are stabilized by coadsorbed CO. A kinetic “foot-in-the-door” model is proposed in which fluctuations in PDI coordination allow CO to diffuse into the gap between gold adatoms to prevent the PDI from reattaching, thereby allowing additional CO to adsorb, to provide kinetic model for allosteric CO adsorption on PDI-covered gold.« less

  19. Exceptional enhancement of H{sub 2} production in alkaline environment over plasmonic Au/TiO{sub 2} photocatalyst under visible light

    SciTech Connect (OSTI)

    Meng, Xianguang; Liu, Guigao; Yu, Qing; Wang, Tao; Chang, Kun; Li, Peng; Liu, Lequan E-mail: Lequan.Liu@tju.edu.cn; Ye, Jinhua E-mail: Lequan.Liu@tju.edu.cn

    2015-10-01

    A reaction environment modulation strategy was employed to promote the H{sub 2} production over plasmonic Au/semiconductor composites. It is shown that the fast consumption of the holes in plasmonic Au nanoparticles by methanol in alkaline reaction environment remarkably increases H{sub 2} generation rate under visible light. The photocatalytic reaction is mainly driven by the interband transition of plasmonic Au nanoparticles, and the apparent quantum efficiency of plasmon-assisted H{sub 2} production at pH 14 reaches 6% at 420 nm. The reaction environment control provides a simple and effective way for the highly efficient solar fuel production from biomass reforming through plasmonic photocatalysis in future.

  20. Wavelengths, transition probabilities, and oscillator strengths for M-shell transitions in Co-, Ni-, Cu-, Zn-, Ga-, Ge-, and Se-like Au ions

    SciTech Connect (OSTI)

    Xu, Min; Jiang, Gang; Deng, Banglin; Bian, Guojie

    2014-11-15

    Wavelengths, transition probabilities, and oscillator strengths have been calculated for M-shell electric dipole transitions in Co-, Ni-, Cu-, Zn-, Ga-, Ge-, and Se-like Au ions. The fully relativistic multiconfiguration Dirac–Fock method, taking quantum electrodynamical effects and the Breit correction into account, was used in the calculations. Calculated energy levels of M-shell excited states for Cu-, Zn-, Ga-, Ge-, and Se-like Au ions from the method were compared with available theoretical and experimental results, and good agreement with them was achieved.

  1. Sulfur Tolerant Pd/Cu and Pd/Au Alloy Membranes for H2 Separation with High Pressure CO2 for Sequestration

    SciTech Connect (OSTI)

    Yi Hua Ma; Natalie Pomerantz; Chao-Huang Chen

    2008-09-30

    The effect of H{sub 2}S poisoning on Pd, Pd/Cu, and Pd/Au alloy composite membranes prepared by the electroless deposition method on porous Inconel supports was investigated to provide a fundamental understanding of the durability and preparation of sulfur tolerant membranes. X-ray photoelectron spectroscopy (XPS) studies showed that the exposure of pure Pd to 50 ppm H{sub 2}S/H{sub 2} mixtures caused bulk sulfide formation at lower temperatures and surface sulfide formation at higher temperatures. Lower temperatures, longer exposure times, and higher H{sub 2}S concentrations resulted in a higher degree of sulfidation. In a Pd membrane, the bulk sulfide formation caused a drastic irrecoverable H{sub 2} permeance decline and an irreparable loss in selectivity. Pd/Cu and Pd/Au alloy membranes exhibited permeance declines due to surface sulfide formation upon exposure to 50 ppm H{sub 2}S/H{sub 2} gas mixtures. However in contrast to the pure Pd membrane, the permeances of the Pd/Cu and Pd/Au alloy membranes were mostly recovered in pure H{sub 2} and the selectivity of the Pd alloy layers remained essentially intact throughout the characterization in H{sub 2}, He and H{sub 2}S/H{sub 2} mixtures which lasted several thousand hours. The amount of irreversible sulfur poisoning decreased with increasing temperature due to the exothermicity of H{sub 2}S adsorption. Longer exposure times increased the amount of irreversible poisoning of the Pd/Cu membrane but not the Pd/Au membrane. Pd/Au coupon studies of the galvanic displacement method showed that higher Au{sup 3+} concentrations, lower pH values, higher bath temperatures and stirring the bath at a rate of 200 rpm yielded faster displacement rates, more uniform depositions, and a higher Au content within the layers. While 400 C was found to be sufficient to form a Pd/Au alloy on the surface, high temperature X-ray diffraction (HTXRD) studies showed that even after annealing between 500-600 C, the Pd/Cu alloys could have part or all of the surface in the less sulfur resistant {beta} phase.

  2. Antiproton Production in 11.5A GeV/c Au+Pb Nucleus-Nucleus Collisions

    SciTech Connect (OSTI)

    De Cataldo, G.; Giglietto, N.; Raino, A.; Spinelli, P.; Huang, H.Z.; Hill, J.C.; Libby, B.; Wohn, F.K.; Rabin, M.S.; Haridas, P.; Pless, I.A.; Van Buren, G.; Armstrong, T.A.; Lewis, R.A.; Reid, J.D.; Smith, G.A.; Toothacker, W.S.; Davies, R.; Hirsch, A.S.; Porile, N.T.; Rimai, A.; Scharenberg, R.P.; Srivastava, B.K.; Tincknell, M.L.; Greene, S.V.; Bennett, S.J.; Cormier, T.M.; Dee, P.; Fachini, P.; Kim, B.; Li, Q.; Li, Y.; Munhoz, M.G.; Pruneau, C.A.; Wilson, W.K.; Zhao, K.; Barish, K.N.; Bennett, M.J.; Chikanian, A.; Coe, S.D.; Diebold, G.E.; Finch, L.E.; George, N.K.; Kumar, B.S.; Lajoie, J.G.; Majka, R.D.; Nagle, J.L.; Pope, J.K.; Rotondo, F.S.; Sandweiss, J.; Slaughter, A.J.; Wolin, E.J.

    1997-11-01

    We present the first results from the E864 Collaboration on the production of antiprotons in 10{percent} central 11.5A GeV /c Au+Pb nucleus collisions at the Brookhaven Alternating Gradient Synchrotron. We report invariant multiplicities for antiproton production in the kinematic region 1.4{lt}y{lt}2.2 and 50{lt} p{sub T}{lt} 300 MeV/c , and compare our data with a first collision scaling model and previously published results from the E878 Collaboration. The differences between the E864 and E878 antiproton measurements and the implications for antihyperon production are discussed. {copyright} {ital 1997} {ital The American Physical Society}

  3. Energy level alignment of self-assembled linear chains of benzenediamine on Au(111) from first principles

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Li, Guo; Rangel, Tonatiuh; Liu, Zhen -Fei; Cooper, Valentino R.; Neaton, Jeffrey B.

    2016-03-24

    Using density functional theory (DFT) with van der Waals functionals, we calculate the adsorption energetics and geometry of benzenediamine (BDA) molecules on Au(111) surfaces. Our results demonstrate that the reported self-assembled linear chain structure of BDA, stabilized via hydrogen bonds between amine groups, is energetically favored over previously-studied monomeric phases. Moreover, using a model based on many-body perturbation theory within the GW approximation, we obtain approximate self-energy corrections to the DFT highest occupied molecular orbital (HOMO) energy associated with BDA adsorbate phases. As a result, we find that, independent of coverage, the HOMO energy of the linear chain phase ismore » lower relative to the Fermi energy than that of the monomer phase, and in good agreement with values measured with ultraviolet photoelectron spectroscopy and X-ray photoelectron spectroscopy.« less

  4. Control of domain wall pinning by localised focused Ga {sup +} ion irradiation on Au capped NiFe nanowires

    SciTech Connect (OSTI)

    Burn, D. M. Atkinson, D.

    2014-10-28

    Understanding domain wall pinning and propagation in nanowires are important for future spintronics and nanoparticle manipulation technologies. Here, the effects of microscopic local modification of the magnetic properties, induced by focused-ion-beam intermixing, in NiFe/Au bilayer nanowires on the pinning behavior of domain walls was investigated. The effects of irradiation dose and the length of the irradiated features were investigated experimentally. The results are considered in the context of detailed quasi-static micromagnetic simulations, where the ion-induced modification was represented as a local reduction of the saturation magnetization. Simulations show that domain wall pinning behavior depends on the magnitude of the magnetization change, the length of the modified region, and the domain wall structure. Comparative analysis indicates that reduced saturation magnetisation is not solely responsible for the experimentally observed pinning behavior.

  5. Study of supported PtCu and PdAu bimetallic nanoparticles using in-situ x-ray tools.

    SciTech Connect (OSTI)

    Oxford, S. M.; Lee, P. L.; Chupas, P. J.; Chapman, K. W.; Kung, M. C.; Kung, H. H.; Northwestern Univ.

    2010-01-01

    A combination of two synchrotron X-ray techniques, X-ray absorption spectroscopy (XAS), and pair distribution function analysis (PDF) with complementary Fourier transform infrared (FTIR) spectroscopy measurement, was used to characterize the composition distributions of PdAu and PtCu bimetallic particles after treatment in H{sub 2} or CO and in the presence of these gases. This is the first reported application of PDF to the study of supported bimetallic nanoparticles. We found that XAS was informative in determining the component distribution of an initial sample, but PDF was better suited to following changes in the distribution upon changing the gas environment. Thus, the surface of a PtCu bimetallic particle of about 2.5 nm after treatment in H{sub 2} was found to be enriched in Cu, while the core was bimetallic. There was no evidence of a component-segregated core?shell structure. Treatment in CO caused enrichment of Pt to the surface layer, with a concomitant migration of Cu to the core. The average particle size remained the same. For the PdAu bimetallic particles, the surface and core compositions were similar after H{sub 2} treatment, and Pd was enriched in the surface after CO treatment. The X-ray results compared favorably to infrared spectroscopy results. The results demonstrated that the two X-ray techniques in combination can generate new information not available with either technique alone or other techniques, about the elemental distribution of bimetallic particles under conditions relevant to catalysis. They could provide new insight into structure-function relationships and time-on-stream behavior of bimetallic catalysts.

  6. Exploring the activity of a novel Au/TiC(001) model catalyst towards CO and CO2 hydrogenation

    SciTech Connect (OSTI)

    Asara, Gian Giacomo; Ricart, Josep M.; Illas, Francesc

    2015-02-02

    Small metallic nanoparticles supported on transition metal carbides exhibit an unexpected high activity towards a series of chemical reactions. In particular, the Au/TiC system has proven to be an excellent catalyst for SO2 decomposition, thiophene hydrodesulfurization, O2 and H2 dissociation and the water gas shift reaction. Recent studies have shown that Au/TiC is a very good catalyst for the reverse water–gas shift (CO2 + H2 → CO + H2O) and CO2 hydrogenation to methanol. The present work further expands the range of applicability of this novel type of systems by exploring the catalytic activity of Au/TiC towards the hydrogenation of CO or CO2 with periodic density functional theory (DFT) calculations on model systems. Hydrogen dissociates easily on Au/TiC but direct hydrogenation of CO to methanol is hindered by very high activation barriers implying that, on this model catalyst, methanol production from CO2 involves the hydrogenation of a HOCO-like intermediate. Thus, when dealing with mixtures of syngas (CO/CO2/H2/H2O), CO could be transformed into CO2 through the water gas shift reaction with subsequent hydrogenation of CO2 to methanol.

  7. Preparation and Characterization of Au-ZrO2-SiO2 Nanocomposite Spheres and Their Application in Enrichment and Detection of Organophosphorus Agents

    SciTech Connect (OSTI)

    Yang, Yuqi; Tu, Haiyang; Zhang, Aidong; Du, Dan; Lin, Yuehe

    2012-03-01

    Au-ZrO{sub 2}-SiO{sub 2} nanocomposite spheres were synthesized and used as selective sorbents for the solid-phase extraction (SPE) of orananophosphorous agents. A non-enzymatic electrochemical sensor based on an Au-ZrO{sub 2}-SiO{sub 2} modified electrode was developed for selective detection of orananophosphorous pesticides (OPs). The Au-ZrO{sub 2}-SiO{sub 2} nanocomposite spheres were synthesized by hydrolysis and condensation of zirconia n-butoxide (TBOZ) on the surface of SiO{sub 2} spheres and then introduction of gold nanoparticles on the surface. Transmission electron microscope and X-ray photoelectron spectroscopy were performed to characterize the formation of the nanocomposite sphere. Fast extraction of OP was achieved by Au-ZrO{sub 2}-SiO{sub 2} modified electrode within 5 min via the specific affinity between zirconia and phosphoric group. The assay yields a broad concentration range of paraoxon-ethyl from 1.0 to 500 ng/mL{sup -1} with a detection limit 0.5 ng/mL{sup -1}. This selective and sensitive method holds great promise for the enrichment and detection of OPs.

  8. Structure-activity relationship of Au-ZrO2 catalyst on formation of hydroxyl groups and its influence on CO oxidation

    SciTech Connect (OSTI)

    Karwacki, Christopher J; Ganesh, Panchapakesan; Kent, P. R. C.; Gordon, Wesley O; Peterson, Gregory W; Niu, Jun Jie; Gogotsi, Yury G.

    2013-01-01

    The effect of changes in morphology and surface hydroxyl species upon thermal treatment of zirconia on the oxidation activity of Au/ZrO2 catalyst was studied. We observed using transmission Fourier transform infrared (FTIR) spectroscopy progressive changes in the presence of monodentate (type I), bidentate (type II) and hydrogen bridged species (type III) for each of the thermally treated (85 to 500 C) supports consisting of bare zirconia and Au/ZrO2 catalysts. Furthermore, structural changes in zirconia were accompanied by an increase in crystal size (7 to 58 nm) and contraction of the supports porosity (SSA 532 to 7 m2 g 1) with increasing thermal treatment. Deposition of gold nanoparticles under similar preparation conditions on different thermally treated zirconia resulted in changes in the mean gold cluster size, ranging from 3.7 to 5.6 nm. Changes in the surface hydroxyl species, support structure and size of the gold centers are important parameters responsible for the observed decrease (>90%) in CO conversion activity for the Au/ZrO2 catalysts. Density functional theory calculations provide evidence of increased CO binding to Au nanoclusters in the presence of surface hydroxyls on zirconia, which increases charge transfer at the perimeter of the gold nanocluster on zirconia support. This further helps in reducing a model CO-oxidation reaction barrier in the presence of surface hydroxyls. This work demonstrates the need to understand the structure activity relationship of both the support and active particles for the design of catalytic materials.

  9. Structure-Activity Relationship of Au/ZrO2 Catalyst on Formation of Hydroxyl Groups and Its Influence on CO Oxidation

    SciTech Connect (OSTI)

    Karwacki, Christopher J; Ganesh, Panchapakesan; Gordon, Wesley O; Peterson, Gregory W; Niu, Jun Jie; Gogotsi, Yury G.

    2013-01-01

    The effect of changes in morphology and surface hydroxyl species upon thermal treatment of zirconia on the oxidation activity of Au/ZrO2 catalyst was studied. We observed using transmission fourier transform infrared (FTIR) spectroscopy progressive changes in the presence of monodentate (type I), bidentate (type II) and hydrogen bridged species (type III) for each of the thermally treated (85 to 500 C) supports consisting of bare zirconia and Au/ZrO2 catalysts. Furthermore, structural changes in zirconia were accompanied by an increase in crystal size (7 to 58 nm) and contraction of the supports porosity (SSA 532 to 7 m2/g) with increasing thermal treatment. Deposition of gold nanoparticles under similar preparation conditions on different thermally treated zirconia resulted in changes in the mean gold cluster size, ranging from 3.7 to 5.6 nm. Changes in the surface hydroxyl species, support structure and size of the gold centers are important parameters responsible for the observed decrease (> 90 %) in CO conversion activity for the Au/ZrO2 catalysts. Density functional theory calculations provide evidence of increased CO binding to Au nanoclusters in the presence of surface hydroxyls on zirconia, which increases charge transfer at the perimeter of the gold nanocluster on zirconia support. This further helps in reducing a model CO-oxidation reaction barrier in the presence of surface hydroxyls. This work demonstrates the need to understand the structure-activity relationship of both the support and active particles for the design of catalytic materials.

  10. THE SOLAR NEIGHBORHOOD. XXVII. DISCOVERY OF NEW PROPER MOTION STARS WITH {mu} {>=} 0.''18 yr{sup -1} IN THE SOUTHERN SKY WITH 16.5 < R{sub 59F} {<=} 18.0

    SciTech Connect (OSTI)

    Boyd, Mark R.; Henry, Todd J.; Jao, Wei-Chun; Subasavage, John P.; Hambly, Nigel C. E-mail: thenry@chara.gsu.edu E-mail: jsubasavage@ctio.noao.edu

    2011-09-15

    Here we present 1584 new southern proper motion systems with {mu} {>=} 0.''18 yr{sup -1} and 16.5 > R{sub 59F} {>=} 18.0. This search complements the six previous SuperCOSMOS-RECONS (SCR) proper motion searches of the southern sky for stars within the same proper motion range, but with R{sub 59F} {<=} 16.5. As in previous papers, we present distance estimates for these systems and find that three systems are estimated to be within 25 pc, including one, SCR 1546-5534, possibly within the RECONS 10 pc horizon at 6.7 pc, making it the second nearest discovery of the searches. We find 97 white dwarf candidates with distance estimates between 10 and 120 pc, as well as 557 cool subdwarf candidates. The subdwarfs found in this paper make up nearly half of the subdwarf systems reported from our SCR searches and are significantly redder than those discovered thus far. The SCR searches have now found 155 red dwarfs estimated to be within 25 pc, including 10 within 10 pc. In addition, 143 white dwarf candidates and 1155 cool subdwarf candidates have been discovered. The 1584 systems reported here augment the sample of 4724 systems previously discovered in our SCR searches and imply that additional systems fainter than R{sub 59F} = 18.0 are yet to be discovered.

  11. Effects of ion and nanosecond-pulsed laser co-irradiation on the surface nanostructure of Au thin films on SiO{sub 2} glass substrates

    SciTech Connect (OSTI)

    Yu, Ruixuan; Meng, Xuan; Takayanagi, Shinya; Shibayama, Tamaki Yatsu, Shigeo; Ishioka, Junya; Watanabe, Seiichi

    2014-04-14

    Ion irradiation and short-pulsed laser irradiation can be used to form nanostructures on the surfaces of substrates. This work investigates the synergistic effects of ion and nanosecond-pulsed laser co-irradiation on surface nanostructuring of Au thin films deposited under vacuum on SiO{sub 2} glass substrates. Gold nanoparticles are randomly formed on the surface of the substrate after nanosecond-pulsed laser irradiation under vacuum at a wavelength of 532 nm with a repetition rate of 10 Hz and laser energy density of 0.124 kJ/m{sup 2}. Gold nanoparticles are also randomly formed on the substrate after 100-keV Ar{sup +} ion irradiation at doses of up to 3.8 × 10{sup 15} ions/cm{sup 2}, and nearly all of these nanoparticles are fully embedded in the substrate. With increasing ion irradiation dose (number of incident laser pulses), the mean diameter of the Au nanoparticles decreases (increases). However, Au nanoparticles are only formed in a periodic surface arrangement after co-irradiation with 6000 laser pulses and 3.8 × 10{sup 15} ions/cm{sup 2}. The periodic distance is ∼540 nm, which is close to the wavelength of the nanosecond-pulsed laser, and the mean diameter of the Au nanoparticles remains at ∼20 nm with a relatively narrow distribution. The photoabsorption peaks of the ion- or nanosecond-pulsed laser-irradiated samples clearly correspond to the mean diameter of Au nanoparticles. Conversely, the photoabsorption peaks for the co-irradiated samples do not depend on the mean nanoparticle diameter. This lack of dependence is likely caused by the periodic nanostructure formed on the surface by the synergistic effects of co-irradiation.

  12. Pull strength evaluation of Sn-Pb solder joints made to Au-Pt-Pd and Au thick film structures on low-temperature co-fired ceramic -final report for the MC4652 crypto-coded switch (W80).

    SciTech Connect (OSTI)

    Uribe, Fernando; Vianco, Paul Thomas; Zender, Gary L.

    2006-06-01

    A study was performed that examined the microstructure and mechanical properties of 63Sn-37Pb (wt.%, Sn-Pb) solder joints made to thick film layers on low-temperature co-fired (LTCC) substrates. The thick film layers were combinations of the Dupont{trademark} 4596 (Au-Pt-Pd) conductor and Dupont{trademark} 5742 (Au) conductor, the latter having been deposited between the 4596 layer and LTCC substrate. Single (1x) and triple (3x) thicknesses of the 4596 layer were evaluated. Three footprint sizes were evaluated of the 5742 thick film. The solder joints exhibited excellent solderability of both the copper (Cu) lead and thick film surface. In all test sample configurations, the 5742 thick film prevented side wall cracking of the vias. The pull strengths were in the range of 3.4-4.0 lbs, which were only slightly lower than historical values for alumina (Al{sub 2}O{sub 3}) substrates. General (qualitative) observations: (a) The pull strength was maximized when the total number of thick film layers was between two and three. Fewer that two layers did not develop as strong of a bond at the thick film/LTCC interface; more than three layers and of increased footprint area, developed higher residual stresses at the thick film/LTCC interface and in the underlying LTCC material that weakened the joint. (b) Minimizing the area of the weaker 4596/LTCC interface (e.g., larger 5742 area) improved pull strength. Specific observations: (a) In the presence of vias and the need for the 3x 4596 thick film, the preferred 4596:5742 ratio was 1.0:0.5. (b) For those LTCC components that require the 3x 4596 layer, but do not have vias, it is preferred to refrain from using the 5742 layer. (c) In the absence of vias, the highest strength was realized with a 1x thick 5742 layer, a 1x thick 4596 layer, and a footprint ratio of 1.0:1.0.

  13. Measurement of long-range angular correlation and quadrupole anisotropy of pions and (anti)protons in central d+Au collisions at sNN=200 GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adare, A.; Aidala, C.; Ajitanand, N. N.; Akiba, Y.; Akimoto, R.; Al-Bataineh, H.; Al-Ta’ani, H.; Alexander, J.; Andrews, K. R.; Angerami, A.; et al

    2015-05-12

    In this study, we present azimuthal angular correlations between charged hadrons and energy deposited in calorimeter towers in central d+Au and aluminum bias p+p collisions at √sNN = 200 GeV. The charged hadron is measured at midrapidity lηl < 0.35, and the energy us measured at large rapidity (–3.7 < η < –3.1, Au-going direction). An enhanced near-side angular correlation across lΔηl > 2.75 is observed in d+Au collisions. Using the event plane method applied to the Au-going energy distribution, we extract the anisotropy strength v₂ for inclusive charged hadrons at midrapidity up to pT = 4.5 GeV/c. We alsomore » present the measurement of v₂ for identified π± and (anti)protons in central d+Au collisions, and observe a mass-ordering pattern similar to that seen in heavy ion collisions. These results are compared with viscous hydrodynamic calculations and measurements from p+Pb at √sNN = 5.02 TeV. The magnitude of the mass-ordering in d+Au is found to be smaller than that in p+Pb collisions, which may indicate smaller radial flow in lower energy d+Au collisions.« less

  14. Understanding the Mechanism of Solvent-Mediated Adhesion of Vacuum Deposited Au and Pt Thin Films onto PMMA Substrates

    SciTech Connect (OSTI)

    Mo, Alan K [ORNL; Brown, Victoria L. [James Madison University; Rugg, Brandon K. [James Madison University; Devore, Prof. Thomas C. [James Madison University; Meyer III, Harry M [ORNL; Hu, Dr. Xiaofeng [James Madison University; Hughes, Prof. W. Christopher [James Madison University; Augustine, Prof. Brian H. [James Madison University

    2012-01-01

    The adhesion of 100 nm thick electron-beam deposited Au and Pt and magnetron sputtered Au thin films onto poly(methyl methacrylate) (PMMA) substrates can be significantly enhanced to over 90% adhesion by either spin-casting or vapor-exposure to hydrohalocarbon solvents prior to metal deposition compared to samples that are either cleaned in isopropyl alcohol or pre-treated with a remote O2 plasma. X-ray photoelectron spectroscopy (XPS) and evolved gas Fourier transform infrared spectroscopy (EGA-FTIR) reveal the presence of residual halogenated solvent molecules at the PMMA surface which chemically activates the surface to produce a stable chemical interaction between the noble metal film and the PMMA. Density functional theory (DFT) calculations show that the halogenated solvent molecules preferentially form a Lewis acid-base adduct with the oxygen atoms in the ester group in PMMA which is consistent with the measured enthalpy of desorption of chloroform (CHCl3) on PMMA determined by EGA-FTIR to be 36 kJ mol-1. The DFT model also supports the experimentally observed change in the high resolution XPS O 1s peak at 533.77 eV after metallization attributed to a change in the local bonding environment of the bridging O in the PMMA ester group. DFT also predicts that the deposited metal atom (M) inserts into the C-X bond where X is the halogen atom on either CHCl3 or bromoform (CHBr3) to form a O M X interaction that is observed by a M-X bond in the high resolution XPS Cl 2p3/2 peak at 198.03 eV and Br 3p3/2 peak at 182.06 eV. A range of solvents with differing polarities for PMMA pre-treatment have been used and it is proposed that non-complexing solvents result in significant metal adhesion improvement. The Gutmann acceptor number can be used to predict the effectiveness of solvent treatment for noble metal adhesion. A model is proposed in which the bond energy of the C-X bond of the solvent must be sufficiently low so that the C-X bond can be cleaved to form the M-X bond. Supporting this model, a negative control of vapor phase exposure to fluoroform (CHF3) is shown to have no effect on noble metal adhesion due to the higher bond dissociation energy of the C-F bond compared to the C-Cl and C-Br bond energy. The surface activation of vapor-phase exposed PMMA surfaces is technologically significant for the fabrication of polymer microdevices requiring Au or Pt metallization.

  15. Reactivity of Au nanoparticles supported over SiO2 and TiO2 studiedby ambient pressure photoelectron spectroscopy

    SciTech Connect (OSTI)

    Herranz, Tirma; Deng, Xingyi; Cabot, Andreu; Alivisatos, Paul; Liu, Zhi; Soler-Illia, Galo; Salmeron, Miquel

    2009-04-15

    The influence of the metal cluster size and the identity of the support on the reactivity of gold based catalysts have been studied in the CO oxidation reaction. To overcome the structural complexity of the supported catalysts, gold nanoparticles synthesized from colloidal chemistry with precisely controlled size have been used. Those particles were supported over SiO{sub 2} and TiO{sub 2} and their catalytic activity was measured in a flow reactor. The reaction rate was dependent on the particle size and the support, suggesting two reaction pathways in the CO oxidation reaction. In parallel, ambient pressure photoelectron spectroscopy (APPS) has been performed under reaction conditions using bidimensional model catalysts prepared upon supporting the Au nanoparticles over planar polycrystalline SiO{sub 2} and TiO{sub 2} thin films by means of the Langmuir-Blodgett (LB) technique to mimic the characteristic of the powder samples. In this way, the catalytically active surface was characterized under true reaction conditions, revealing that during CO oxidation gold remains in the metallic state.

  16. Multishell Au/Ag/SiO2 nanorods with tunable optical properties as single particle orientation and rotational tracking probes

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Chen, Kuangcai; Lin, Chia -Cheng; Vela, Javier; Fang, Ning

    2015-04-07

    In this study, three-layer core–shell plasmonic nanorods (Au/Ag/SiO2–NRs), consisting of a gold nanorod core, a thin silver shell, and a thin silica layer, were synthesized and used as optical imaging probes under a differential interference contrast microscope for single particle orientation and rotational tracking. The localized surface plasmon resonance modes were enhanced upon the addition of the silver shell, and the anisotropic optical properties of gold nanorods were maintained. The silica coating enables surface functionalization with silane coupling agents and provides enhanced stability and biocompatibility. Taking advantage of the longitudinal LSPR enhancement, the orientation and rotational information of the hybridmore » nanorods on synthetic lipid bilayers and on live cell membranes were obtained with millisecond temporal resolution using a scientific complementary metal-oxide-semiconductor camera. The results demonstrate that the as-synthesized hybrid nanorods are promising imaging probes with improved sensitivity and good biocompatibility for single plasmonic particle tracking experiments in biological systems.« less

  17. The analysis of leakage current in MIS Au/SiO{sub 2}/n-GaAs at room temperature

    SciTech Connect (OSTI)

    Altuntas, H.; Ozcelik, S.

    2013-10-15

    The aim of this study is to determine the reverse-bias leakage current conduction mechanisms in Au/SiO{sub 2}/n-GaAs metal-insulator-semiconductor type Schottky contacts. Reverse-bias current-voltage measurements (I-V) were performed at room temperature. The using of leakage current values in SiO{sub 2} at electric fields of 1.46-3.53 MV/cm, ln(J/E) vs. {radical}E graph showed good linearity. Rom this plot, dielectric constant of SiO{sub 2} was calculated as 3.7 and this value is perfect agreement with 3.9 which is value of SiO{sub 2} dielectric constant. This indicates, Poole-Frenkel type emission mechanism is dominant in this field region. On the other hand, electric fields between 0.06-0.73 and 0.79-1.45 MV/cm, dominant leakage current mechanisms were found as ohmic type conduction and space charge limited conduction, respectively.

  18. Photocatalytic and antibacterial properties of Au-TiO{sub 2} nanocomposite on monolayer graphene: From experiment to theory

    SciTech Connect (OSTI)

    He, Wangxiao; Huang, Hongen; Yan, Jin; Zhu, Jian; The Key Laboratory of Biomedical Information Engineering of Ministry of Education, Xi'an Jiaotong University, Xi'an 710049

    2013-11-28

    The formation of the Au-TiO{sub 2} nanocomposite on monolayer Graphene (GTA) by sequentially depositing titanium dioxide particles and gold nanoparticles on graphene sheet was synthesized and analyzed in our work. The structural, morphological, and physicochemical properties of samples were thoroughly investigated by UV-Vis spectrophotometer, Raman spectroscopy, Fourier transform infrared spectroscopy, atomic force microscopy, scanning electron microscope, and transmission electron microscope. Photocatalytic performance of GTA, graphene (GR), TiO{sub 2,} and TiO{sub 2} -graphene nanocomposite (GT) were comparatively studied for degradation of methyl orange, and it was found that GTA had highest performance among all samples. More importantly, antibacterial performance of this novel composite against Gram-positive bacteria, Gram-negative bacteria, and fungus was predominant compared to GR, TiO{sub 2}, and GT. And the result of biomolecules oxidation tests suggested that antimicrobial actions were contributed by oxidation stress on both membrane and antioxidant systems. Besides, the rate of two decisive processes during photocatalytic reaction, the rate of the charge transfer (k{sub CT}) and the rate of the electron-hole recombination (k{sub R}) have been studied by Perturbation theory, Radiation theory, and Schottky barrier theory. Calculation and derivation results show that GTA possesses superior charge separation and transfer rate, which gives an explanation for the excellent oxidation properties of GTA.

  19. Microstructure of Co/X (X=Cu,Ag,Au) epitaxial thin films grown on Al{sub 2}O{sub 3}(0001) substrates

    SciTech Connect (OSTI)

    Ohtake, Mitsuru; Akita, Yuta; Futamoto, Masaaki; Kirino, Fumiyoshi

    2007-05-01

    Epitaxial thin films of Co/X (X=Cu,Ag,Au) were prepared on Al{sub 2}O{sub 3}(0001) substrates at substrate temperatures of 100 and 300 degree sign C by UHV molecular beam epitaxy. A complicated microstructure was realized for the epitaxial thin films. In-situ reflection high-energy electron diffraction observation has shown that X atoms of the buffer layer segregated to the surface during Co layer deposition, and it yielded a unique epitaxial granular structure. The structure consists of small Co grains buried in the X buffer layer, where both the magnetic small Co grains and the nonmagnetic X layer are epitaxially grown on the single crystal substrate. The structure varied depending on the X element and the substrate temperature. The crystal structure of Co grains is influenced by the buffer layer material and determined to be hcp and fcc structures for the buffer layer materials of Au and Cu, respectively.

  20. Measurements of elliptic and triangular flow in high-multiplicity 3He+Au collisions at √sNN=200 GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adare, A.

    2015-09-28

    We present the first measurement of elliptic (v2) and triangular (v3) flow in high-multiplicity 3He+Aucollisions at √sNN=200 GeV. Two-particle correlations, where the particles have a large separation in pseudorapidity, are compared in 3He+Au and in p+p collisions and indicate that collective effects dominate the second and third Fourier components for the correlations observed in the 3He+Ausystem. The collective behavior is quantified in terms of elliptic v2 and triangular v3 anisotropy coefficients measured with respect to their corresponding event planes. The v2 values are comparable to those previously measured in d+Au collisions at the same nucleon-nucleon center-of-mass energy. Comparisons with variousmore » theoretical predictions are made, including to models where the hot spots created by the impact of the three 3He nucleons on the Au nucleus expand hydrodynamically to generate the triangular flow. The agreement of these models with data may indicate the formation of low-viscosity quark-gluon plasma even in these small collision systems.« less

  1. The Vital Function of Fe3O4@Au nanocomposites for Hydrolase Biosensor Design and Its Application in Detection of Methyl Parathion

    SciTech Connect (OSTI)

    Zhao, Yuting; Zhang, Weiying; Lin, Yuehe; Du, Dan

    2013-02-04

    A nanocomposite of gold nanoparticles (AuNPs) decorating a magnetic Fe3O4 core was synthesized using cysteamine (SHNH2) as linker, and characterized by TEM, XPS, UV and electrochemistry. Then a hydrolase biosensor, based on self-assembly of methyl parathion hydrolase (MPH) on the Fe3O4@Au nanocomposite, was developed for sensitive and selective detection of the organophosphorus pesticide (OP) methyl parathion. The magnetic nanocomposite provides an easy way to construct the enzyme biosensor by simply exerting an external magnetic field, and also provides a simple way to renew the electrode surface by removing the magnet. Unlike inhibition-based enzyme biosensors, the hydrolase is not poisoned by OPs and thus is reusable for continuous measurement. AuNPs not only provide a large surface area, high loading efficiency and fast electron transfer, but also stabilize the enzyme through electrostatic interactions. The MPH biosensor shows rapid response and high selectivity for detection of methyl parathion, with a linear range from 0.5 to 1000 ng/mL and a detection limit of 0.1 ng/mL. It also shows acceptable reproducibility and stability. The simplicity and ease of operation of the proposed method has great potential for on-site detection of PS containing pesticides and provides a promising strategy to construct a robust biosensor.

  2. Measurements of elliptic and triangular flow in high-multiplicity 3He+Au collisions at ?sNN=200 GeV

    SciTech Connect (OSTI)

    Adare, A.

    2015-09-28

    We present the first measurement of elliptic (v2) and triangular (v3) flow in high-multiplicity 3He+Aucollisions at ?sNN=200 GeV. Two-particle correlations, where the particles have a large separation in pseudorapidity, are compared in 3He+Au and in p+p collisions and indicate that collective effects dominate the second and third Fourier components for the correlations observed in the 3He+Ausystem. The collective behavior is quantified in terms of elliptic v2 and triangular v3 anisotropy coefficients measured with respect to their corresponding event planes. The v2 values are comparable to those previously measured in d+Au collisions at the same nucleon-nucleon center-of-mass energy. Comparisons with various theoretical predictions are made, including to models where the hot spots created by the impact of the three 3He nucleons on the Au nucleus expand hydrodynamically to generate the triangular flow. The agreement of these models with data may indicate the formation of low-viscosity quark-gluon plasma even in these small collision systems.

  3. Measurements of elliptic and triangular flow in high-multiplicity 3He+Au collisions at √sNN=200 GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adare, A.

    2015-09-28

    We present the first measurement of elliptic (v2) and triangular (v3) flow in high-multiplicity 3He+Aucollisions at √sNN=200 GeV. Two-particle correlations, where the particles have a large separation in pseudorapidity, are compared in 3He+Au and in p+p collisions and indicate that collective effects dominate the second and third Fourier components for the correlations observed in the 3He+Ausystem. The collective behavior is quantified in terms of elliptic v2 and triangular v3 anisotropy coefficients measured with respect to their corresponding event planes. The v2 values are comparable to those previously measured in d+Au collisions at the same nucleon-nucleon center-of-mass energy. Comparisons with variousmore »theoretical predictions are made, including to models where the hot spots created by the impact of the three 3He nucleons on the Au nucleus expand hydrodynamically to generate the triangular flow. The agreement of these models with data may indicate the formation of low-viscosity quark-gluon plasma even in these small collision systems.« less

  4. Photoelectron imaging and theoretical study on the structure and chemical binding of the mixed-ligand M(I) complexes, [HMSH]{sup ?} (M = Cu, Ag, and Au)

    SciTech Connect (OSTI)

    Qin, Zhengbo; Liu, Zhiling; Cong, Ran; Xie, Hua; Tang, Zichao, E-mail: zctang@dicp.ac.cn, E-mail: fanhj@dicp.ac.cn; Fan, Hongjun, E-mail: zctang@dicp.ac.cn, E-mail: fanhj@dicp.ac.cn [State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China)] [State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China)

    2014-03-21

    We have reported a combined photoelectron imaging and theoretical study on gaseous mixed-ligand M(I) complexes of [HMSH]{sup ?} (M = Cu, Ag, and Au). With the aid of Franck-Condon simulations, vibrationally resolved photoelectron spectra yield accurate electron affinities of 3.269(6), 3.669(10), and 3.591(6) eV for [HCuSH], [HAgSH], and [HAuSH], respectively. And low-frequency modes are observed: 368(12) cm{sup ?1} for [HCuSH], 286(12) cm{sup ?1} for [HAgSH], and 327(12) cm{sup ?1} for [HAuSH], respectively. Extensive theoretical calculations are performed to aid in the spectral assignments and the calculated values agree well with the experimental observations. Although the S and H atoms have little discrepancy in electronegativity (2.20 for H and 2.54 for S), distinct bonding properties are demonstrated between HM and MS bond. It is revealed that there exists significant ionic bonding between MS in [HMSH]{sup ?} (M = Cu, Ag, and Au), while a gradual transition from ionic behavior between HCu in [HCuSH]{sup ?} to quite strong covalent bonding between HAu in [HAuSH]{sup ?}, supported by a variety of chemical bonding analyses.

  5. Measurement of long-range angular correlation and quadrupole anisotropy of pions and (anti)protons in central d+Au collisions at sNN=200 GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adare, A.; Aidala, C.; Ajitanand, N. N.; Akiba, Y.; Akimoto, R.; Al-Bataineh, H.; Al-Ta’ani, H.; Alexander, J.; Andrews, K. R.; Angerami, A.; et al

    2015-05-12

    In this study, we present azimuthal angular correlations between charged hadrons and energy deposited in calorimeter towers in central d+Au and aluminum bias p+p collisions at √sNN = 200 GeV. The charged hadron is measured at midrapidity lηl 2.75 is observed in d+Au collisions. Using the event plane method applied to the Au-going energy distribution, we extract the anisotropy strength v₂ for inclusive charged hadrons at midrapidity up to pT = 4.5 GeV/c. We alsomore »present the measurement of v₂ for identified π± and (anti)protons in central d+Au collisions, and observe a mass-ordering pattern similar to that seen in heavy ion collisions. These results are compared with viscous hydrodynamic calculations and measurements from p+Pb at √sNN = 5.02 TeV. The magnitude of the mass-ordering in d+Au is found to be smaller than that in p+Pb collisions, which may indicate smaller radial flow in lower energy d+Au collisions.« less

  6. Measurement of long-range angular correlation and quadrupole anisotropy of pions and (anti)protons in central d+Au collisions at ?s NN = 200 GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adare, A.

    2015-05-12

    We present azimuthal angular correlations between charged hadrons and energy deposited in calorimeter towers in central d+Au and aluminum bias p+p collisions at ?s NN = 200 GeV. The charged hadron is measured at midrapidity l?l 2.75 is observed in d+Au collisions. Using the event plane method applied to the Au-going energy distribution, we extract the anisotropy strength v? for inclusive charged hadrons at midrapidity up to pT = 4.5 GeV/c. We also present themoremeasurement of v? for identified ? and (anti)protons in central d+Au collisions, and observe a mass-ordering pattern similar to that seen in heavy ion collisions. These results are compared with viscous hydrodynamic calculations and measurements from p+Pb at ?s NN = 5.02 TeV. The magnitude of the mass-ordering in d+Au is found to be smaller than that in p+Pb collisions, which may indicate smaller radial flow in lower energy d+Au collisions.less

  7. Current transient spectroscopy for trapping analysis on Au-free AlGaN/GaN Schottky barrier diode

    SciTech Connect (OSTI)

    Hu, J. Groeseneken, G.; Stoffels, S.; Lenci, S.; Venegas, R.; Decoutere, S.; Bakeroot, B.

    2015-02-23

    This paper presents a combined technique of high voltage off-state stress and current transient measurements to investigate the trapping/de-trapping characteristics of Au-free AlGaN/GaN Schottky barrier diodes. The device features a symmetric three-terminal structure with a central anode contact surrounded by two separate cathodes. Under the diode off-state stress conditions, the two separate cathodes were electrically shorted. The de-trapping dynamics was studied by monitoring the recovery of the two-dimensional electron gas (2DEG) current at different temperatures by applying 0.5?V at cathode 2 while grounding cathode 1. During the recovery, the anode contact acts as a sensor of changes in diode leakage current. This leakage variation was found to be mainly due to the barrier height variation. With this method, the energy level and capture cross section of different traps in the AlGaN/GaN Schottky barrier diode can be extracted. Furthermore, the physical location of different trapping phenomena is indicated by studying the variation of the diode leakage current during the recovery. We have identified two distinct trapping mechanisms: (i) electron trapping at the AlGaN surface in the vicinity of the Schottky contact which results in the leakage reduction (barrier height ?{sub B} increase) together with R{sub ON} degradation; (ii) the electron trapping in the GaN channel layer which partially depletes the 2DEG. The physical origin of the two different traps is discussed in the text.

  8. Connecting speeds, directions and arrival times of 22 coronal mass ejections from the sun to 1 AU

    SciTech Connect (OSTI)

    Mstl, C.; Veronig, A. M.; Rollett, T.; Temmer, M.; Peinhart, V.; Amla, K.; Hall, J. R.; Liewer, P. C.; De Jong, E. M.; Colaninno, R. C.; Davies, J. A.; Harrison, R. A.; Lugaz, N.; Farrugia, C. J.; Galvin, A. B.; Liu, Y. D.; Luhmann, J. G.; Vrnak, B.

    2014-06-01

    Forecasting the in situ properties of coronal mass ejections (CMEs) from remote images is expected to strongly enhance predictions of space weather and is of general interest for studying the interaction of CMEs with planetary environments. We study the feasibility of using a single heliospheric imager (HI) instrument, imaging the solar wind density from the Sun to 1 AU, for connecting remote images to in situ observations of CMEs. We compare the predictions of speed and arrival time for 22 CMEs (in 2008-2012) to the corresponding interplanetary coronal mass ejection (ICME) parameters at in situ observatories (STEREO PLASTIC/IMPACT, Wind SWE/MFI). The list consists of front- and backsided, slow and fast CMEs (up to 2700 km s{sup 1}). We track the CMEs to 34.9 7.1 deg elongation from the Sun with J maps constructed using the SATPLOT tool, resulting in prediction lead times of 26.4 15.3 hr. The geometrical models we use assume different CME front shapes (fixed-?, harmonic mean, self-similar expansion) and constant CME speed and direction. We find no significant superiority in the predictive capability of any of the three methods. The absolute difference between predicted and observed ICME arrival times is 8.1 6.3 hr (rms value of 10.9 hr). Speeds are consistent to within 284 288 km s{sup 1}. Empirical corrections to the predictions enhance their performance for the arrival times to 6.1 5.0 hr (rms value of 7.9 hr), and for the speeds to 53 50 km s{sup 1}. These results are important for Solar Orbiter and a space weather mission positioned away from the Sun-Earth line.

  9. Search for dark photons from neutral meson decays in p+p and d+Au collisions at √sNN = 200 GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adare, A.; Afanasiev, S.; Aidala, C.; Ajitanand, N. N.; Akiba, Y.; Akimoto, R.; Al-Bataineh, H.; Al-Ta'ani, H.; Alexander, J.; Alfred, M.; et al

    2015-03-10

    In this study, the standard model (SM) of particle physics is spectacularly successful, yet the measured value of the muon anomalous magnetic moment (g-2)μ deviates from SM calculations by 3.6σ. Several theoretical models attribute this to the existence of a “dark photon,” an additional U(1) gauge boson, which is weakly coupled to ordinary photons. The PHENIX experiment at the Relativistic Heavy Ion Collider has searched for a dark photon, U, in π⁰, η → γe⁺e⁻ decays and obtained upper limits of O(2×10⁻⁶) on U-γ mixing at 90% CL for the mass range 30 < mU < 90 MeV/c². Combined withmore » other experimental limits, the remaining region in the U-γ mixing parameter space that can explain the (g-2)μ deviation from its SM value is nearly completely excluded at the 90% confidence level, with only a small region of 29 < mU < 32 MeV/c² remaining.« less

  10. B \\to Mu Mu And B \\to Tau Nu Decays (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Org: SLAC National Accelerator Laboratory (SLAC) Sponsoring Org: US DOE Office of Science (DOE SC) Country of Publication: United States Language: English Subject: Experiment-HE...

  11. Measurement of K0S and K*0 in p+p, d+Au, and Cu+Cu collisions at sqrt SNN = 200 GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adare, A.; Aidala, C.

    2014-11-01

    The PHENIX experiment at the Relativistic Heavy Ion Collider has performed a systematic study of K0S and K*0 meson production at midrapidity in p+p, d+Au, and Cu+Cu collisions at sqrt SNN = 200 GeV. The K0S and K*0 mesons are reconstructed via their K0S and π0(→γγ)π0 (→γγ) and K*0 → K ±#25;π± decay modes, respectively. The measured transverse-momentum spectra are used to determine the nuclear modification factor of K0S and K*0 mesons in d+Au and Cu+Cu collisions at different centralities. In the d+Au collisions, the nuclear modification factor of K0S and K*0 mesons is almost constant as a function ofmore » transverse momentum and is consistent with unity showing that cold-nuclear-matter effects do not play a significant role in the measured kinematic range. In Cu+Cu collisions, within the uncertainties no nuclear modification is registered in peripheral collisions. In central collisions, both mesons show suppression relative to the expectations from the p+p yield scaled by the number of binary nucleon-nucleon collisions in the Cu+Cu system. In the pT range 2–5 GeV/c, the strange mesons ( K0S, K*0) similarly to the #30;Φ meson with hidden strangeness, show an intermediate suppression between the more suppressed light quark mesons (π0) and the nonsuppressed baryons (p, p-bar). At higher transverse momentum, pT > 5 GeV/c, production of all particles is similarly suppressed by a factor of ≈2. (auth)« less

  12. The currentvoltage and capacitancevoltage characteristics at high temperatures of Au Schottky contact to n-type GaAs

    SciTech Connect (OSTI)

    zerli, Halil; Karteri, ?brahim; Karata?, ?kr; Altindal, ?emsettin

    2014-05-01

    Highlights: The electronic parameters of the diode under temperature were investigated. The barrier heights have a Gaussian distribution. Au/n-GaAs diode exhibits a rectification behavior. - Abstract: We have investigated the temperature-dependent currentvoltage (IV) and capacitancevoltage (CV) characteristics of Au/n-GaAs Schottky barrier diodes (SBDs) in the temperature range of 280415 K. The barrier height for the Au/n-type GaAs SBDs from the IV and CV characteristics have varied from 0.901 eV to 0.963 eV (IV) and 1.234 eV to 0.967 eV (CV), and the ideality factor (n) from 1.45 to 1.69 in the temperature range 280415 K. The conventional Richardson plots are found to be linear in the temperature range measured. Both the ln(I{sub 0}/T{sup 2}) versus (kT){sup ?1} and ln(I{sub 0}/T{sup 2}) versus (nkT){sup ?1} plots gives a straight line corresponding to activation energies 0.773 eV and 0.870 eV, respectively. A ?{sub b0} versus 1/T plot was drawn to obtain evidence of a Gaussian distribution of the BHs, and values of ?{sup }{sub b0} = 1.071 eV and ?{sub 0} = 0.094 V for the mean BH and zero-bias standard deviation have been obtained from this plot.

  13. Measurement of K0S and K*0 in p+p, d+Au, and Cu+Cu collisions at sqrt SNN = 200 GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adare, A.; Aidala, C.

    2014-11-01

    The PHENIX experiment at the Relativistic Heavy Ion Collider has performed a systematic study of K0S and K*0 meson production at midrapidity in p+p, d+Au, and Cu+Cu collisions at sqrt SNN = 200 GeV. The K0S and K*0 mesons are reconstructed via their K0S and π0(→γγ)π0 (→γγ) and K*0 → K ±#25;π± decay modes, respectively. The measured transverse-momentum spectra are used to determine the nuclear modification factor of K0S and K*0 mesons in d+Au and Cu+Cu collisions at different centralities. In the d+Au collisions, the nuclear modification factor of K0S and K*0 mesons is almost constant as a function ofmore »transverse momentum and is consistent with unity showing that cold-nuclear-matter effects do not play a significant role in the measured kinematic range. In Cu+Cu collisions, within the uncertainties no nuclear modification is registered in peripheral collisions. In central collisions, both mesons show suppression relative to the expectations from the p+p yield scaled by the number of binary nucleon-nucleon collisions in the Cu+Cu system. In the pT range 2–5 GeV/c, the strange mesons ( K0S, K*0) similarly to the #30;Φ meson with hidden strangeness, show an intermediate suppression between the more suppressed light quark mesons (π0) and the nonsuppressed baryons (p, p-bar). At higher transverse momentum, pT > 5 GeV/c, production of all particles is similarly suppressed by a factor of ≈2. (auth)« less

  14. C{sub 6}H{sub 6}/Au(111): Interface dipoles, band alignment, charging energy, and van der Waals interaction

    SciTech Connect (OSTI)

    Abad, E.; Martinez, J. I.; Flores, F.; Ortega, J.; Dappe, Y. J.

    2011-01-28

    We analyze the benzene/Au(111) interface taking into account charging energy effects to properly describe the electronic structure of the interface and van der Waals interactions to obtain the adsorption energy and geometry. We also analyze the interface dipoles and discuss the barrier formation as a function of the metal work-function. We interpret our DFT calculations within the induced density of interface states (IDIS) model. Our results compare well with experimental and other theoretical results, showing that the dipole formation of these interfaces is due to the charge transfer between the metal and benzene, as described in the IDIS model.

  15. d-alpha correlation functions and collective motion in Xe+Au collisions at E/A=50 MeV

    SciTech Connect (OSTI)

    Verde, G; Danielewicz, P; Lynch, W; Chan, C; Gelbke, C; Kwong, L; Liu, T; Liu, X; Seymour, D; Tan, W; Tsang, M; Wagner, A; Xu, H; Brown, D; Davin, B; Larochelle, Y; de Souza, R; Charity, R; Sobotka, L

    2006-07-27

    The interplay of the effects of geometry and collective motion on d-{alpha} correlation functions is investigated for central Xe+Au collisions at E/A=50 MeV. The data cannot be explained with out collective motion, which could be partly along the beam axis. A semi-quantitative description of the data can be obtained using a Monte -Carlo model, where thermal emission is superimposed on collective motion. Both the emission volume and the competition between the thermal and collective motion influence significantly the shape of the correlation function, motivating new strategies for extending intensity interferometry studies to massive particles.

  16. Temperature dependence of contact resistance for Au-Ti-Pd{sub 2}Si-n{sup +}-Si ohmic contacts subjected to microwave irradiation

    SciTech Connect (OSTI)

    Belyaev, A. E.; Boltovets, N. S.; Konakova, R. V. Kudryk, Ya. Ya.; Sachenko, A. V.; Sheremet, V. N.; Vinogradov, A. O.

    2012-03-15

    Based on a theoretical analysis of the temperature dependence of the contact resistance R{sub c} for an Au-Ti-Pd{sub 2}Si-n{sup +}-Si ohmic contact, a current-transfer mechanism explaining the experimentally observed increase in R{sub c} in the temperature range 100-380 K is proposed. It is shown that microwave treatment of such contacts results in a decrease in the spread of R{sub c} over the wafer and a decrease in the value of R{sub c} whilst retaining an increase in R{sub c} in the temperatures range 100-380 K.

  17. Observation of D0 meson nuclear modifications in Au+Au collisions at sNN=200 GeV

    SciTech Connect (OSTI)

    Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alekseev, I.; Alford, J.; Anson, C. D.; Aparin, A.; Arkhipkin, D.; Aschenauer, E. C.; Averichev, G. S.; Banerjee, A.; Beavis, D. R.; Bellwied, R.; Bhasin, A.; Bhati, A. K.; Bhattarai, P.; Bichsel, H.; Bielcik, J.; Bielcikova, J.; Bland, L. C.; Bordyuzhin, I. G.; Borowski, W.; Bouchet, J.; Brandin, A. V.; Brovko, S. G.; Bültmann, S.; Bunzarov, I.; Burton, T. P.; Butterworth, J.; Caines, H.; Calderón de la Barca Sánchez, M.; Cebra, D.; Cendejas, R.; Cervantes, M. C.; Chaloupka, P.; Chang, Z.; Chattopadhyay, S.; Chen, H. F.; Chen, J. H.; Chen, L.; Cheng, J.; Cherney, M.; Chikanian, A.; Christie, W.; Chwastowski, J.; Codrington, M. J. M.; Contin, G.; Cramer, J. G.; Crawford, H. J.; Cui, X.; Das, S.; Davila Leyva, A.; De Silva, L. C.; Debbe, R. R.; Dedovich, T. G.; Deng, J.; Derevschikov, A. A.; Derradi de Souza, R.; Dhamija, S.; di Ruzza, B.; Didenko, L.; Dilks, C.; Ding, F.; Djawotho, P.; Dong, X.; Drachenberg, J. L.; Draper, J. E.; Du, C. M.; Dunkelberger, L. E.; Dunlop, J. C.; Efimov, L. G.; Engelage, J.; Engle, K. S.; Eppley, G.; Eun, L.; Evdokimov, O.; Eyser, O.; Fatemi, R.; Fazio, S.; Fedorisin, J.; Filip, P.; Finch, E.; Fisyak, Y.; Flores, C. E.; Gagliardi, C. A.; Gangadharan, D. R.; Garand, D.; Geurts, F.; Gibson, A.; Girard, M.; Gliske, S.; Greiner, L.; Grosnick, D.; Gunarathne, D. S.; Guo, Y.; Gupta, A.; Gupta, S.; Guryn, W.; Haag, B.; Hamed, A.; Han, L.-X.; Haque, R.; Harris, J. W.; Heppelmann, S.; Hirsch, A.; Hoffmann, G. W.; Hofman, D. J.; Horvat, S.; Huang, B.; Huang, H. Z.; Huang, X.; Huck, P.; Humanic, T. J.; Igo, G.; Jacobs, W. W.; Jang, H.; Judd, E. G.; Kabana, S.; Kalinkin, D.; Kang, K.; Kauder, K.; Ke, H. W.; Keane, D.; Kechechyan, A.; Kesich, A.; Khan, Z. H.; Kikola, D. P.; Kisel, I.; Kisiel, A.; Koetke, D. D.; Kollegger, T.; Konzer, J.; Koralt, I.; Kotchenda, L.; Kraishan, A. F.; Kravtsov, P.; Krueger, K.; Kulakov, I.; Kumar, L.; Kycia, R. A.; Lamont, M. A. C.; Landgraf, J. M.; Landry, K. D.; Lauret, J.; Lebedev, A.; Lednicky, R.; Lee, J. H.; LeVine, M. J.; Li, C.; Li, W.; Li, X.; Li, X.; Li, Y.; Li, Z. M.; Lisa, M. A.; Liu, F.; Ljubicic, T.; Llope, W. J.; Lomnitz, M.; Longacre, R. S.; Luo, X.; Ma, G. L.; Ma, Y. G.; Madagodagettige Don, D. M. M. D.; Mahapatra, D. P.; Majka, R.; Margetis, S.; Markert, C.; Masui, H.; Matis, H. S.; McDonald, D.; McShane, T. S.; Minaev, N. G.; Mioduszewski, S.; Mohanty, B.; Mondal, M. M.; Morozov, D. A.; Mustafa, M. K.; Nandi, B. K.; Nasim, Md.; Nayak, T. K.; Nelson, J. M.; Nigmatkulov, G.; Nogach, L. V.; Noh, S. Y.; Novak, J.; Nurushev, S. B.; Odyniec, G.; Ogawa, A.; Oh, K.; Ohlson, A.; Okorokov, V.; Oldag, E. W.; Olvitt, D. L.; Pachr, M.; Page, B. S.; Pal, S. K.; Pan, Y. X.; Pandit, Y.; Panebratsev, Y.; Pawlak, T.; Pawlik, B.; Pei, H.; Perkins, C.; Peryt, W.; Pile, P.; Planinic, M.; Pluta, J.; Poljak, N.; Porter, J.; Poskanzer, A. M.; Pruthi, N. K.; Przybycien, M.; Pujahari, P. R.; Putschke, J.; Qiu, H.; Quintero, A.; Ramachandran, S.; Raniwala, R.; Raniwala, S.; Ray, R. L.; Riley, C. K.; Ritter, H. G.; Roberts, J. B.; Rogachevskiy, O. V.; Romero, J. L.; Ross, J. F.; Roy, A.; Ruan, L.; Rusnak, J.; Rusnakova, O.; Sahoo, N. R.; Sahu, P. K.; Sakrejda, I.; Salur, S.; Sandweiss, J.; Sangaline, E.; Sarkar, A.; Schambach, J.; Scharenberg, R. P.; Schmah, A. M.; Schmidke, W. B.; Schmitz, N.; Seger, J.; Seyboth, P.; Shah, N.; Shahaliev, E.; Shanmuganathan, P. V.; Shao, M.; Sharma, B.; Shen, W. Q.; Shi, S. S.; Shou, Q. Y.; Sichtermann, E. P.; Singaraju, R. N.; Skoby, M. J.; Smirnov, D.; Smirnov, N.; Solanki, D.; Sorensen, P.; Spinka, H. M.; Srivastava, B.; Stanislaus, T. D. S.; Stevens, J. R.; Stock, R.; Strikhanov, M.; Stringfellow, B.; Sumbera, M.; Sun, X.; Sun, X. M.; Sun, Y.; Sun, Z.; Surrow, B.; Svirida, D. N.; Symons, T. J. M.; Szelezniak, M. A.; Takahashi, J.; Tang, A. H.; Tang, Z.; Tarnowsky, T.; Thomas, J. H.; Timmins, A. R.; Tlusty, D.; Tokarev, M.; Trentalange, S.; Tribble, R. E.; Tribedy, P.; Trzeciak, B. A.; Tsai, O. D.; Turnau, J.; Ullrich, T.; Underwood, D. G.; Van Buren, G.; van Nieuwenhuizen, G.; Vandenbroucke, M.; Vanfossen, J. A.; Varma, R.; Vasconcelos, G. M. S.; Vasiliev, A. N.; Vertesi, R.; Videbæk, F.; Viyogi, Y. P.; Vokal, S.; Vossen, A.; Wada, M.; Wang, F.; Wang, G.; Wang, H.; Wang, J. S.; Wang, X. L.; Wang, Y.; Wang, Y.; Webb, G.; Webb, J. C.; Westfall, G. D.; Wieman, H.; Wissink, S. W.; Witt, R.; Wu, Y. F.; Xiao, Z.; Xie, W.; Xin, K.; Xu, H.; Xu, J.; Xu, N.; Xu, Q. H.; Xu, Y.; Xu, Z.; Yan, W.; Yang, C.; Yang, Y.; Yang, Y.; Ye, Z.; Yepes, P.; Yi, L.; Yip, K.; Yoo, I.-K.; Yu, N.; Zawisza, Y.; Zbroszczyk, H.; Zha, W.; Zhang, J. B.; Zhang, J. L.; Zhang, S.; Zhang, X. P.; Zhang, Y.; Zhang, Z. P.; Zhao, F.; Zhao, J.; Zhong, C.; Zhu, X.; Zhu, Y. H.; Zoulkarneeva, Y.; Zyzak, M.

    2014-09-30

    We report the first measurement of charmed-hadron (D0) production via the hadronic decay channel (D0→K-+) in Au+Au collisions at √sNN=200 GeV with the STAR experiment. The charm production cross section per nucleon-nucleon collision at midrapidity scales with the number of binary collisions, Nbin, from p+p to central Au+Au collisions. The D0 meson yields in central Au+Aucollisions are strongly suppressed compared to those in p+p scaled by Nbin, for transverse momenta pT>3 GeV/c, demonstrating significant energy loss of charm quarks in the hot and dense medium. An enhancement at intermediate pT is also observed. Model calculations including strong charm-medium interactions and coalescence hadronization describe our measurements.

  18. Quantitative Phase Composition of TiO2-Coated Nanoporous-Au Monoliths by X-ray Absorption Spectroscopy and Correlations to Catalytic

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Bagge-Hansen, Michael; Wichmann, Andre; Wittstock, Arne; Lee, Jonathan R. I.; Ye, Jianchao; Willey, Trevor M.; Kuntz, Joshua D.; van Buuren, Tony; Biener, Juergen; Baumer, Marcus; et al

    2014-02-03

    Porous titania/metal composite materials have many potential applications in the fields of green catalysis, energy harvesting, and storage in which both the overall morphology of the nanoporous host material and the crystallographic phase of the titania (TiO 2) guest determine the material’s performance. New insights into the structure–function relationships of these materials were obtained by near-edge X-ray absorption fine structure (NEXAFS) spectroscopy that, for example, provides quantitative crystallographic phase composition from ultrathin, nanostructured titania films, including sensitivity to amorphous components. We demonstrate that crystallographic phase, morphology, and catalytic activity of TiO 2-functionalized nanoporous gold (np-Au) can be controlled by amore » simple annealing procedure (T < 1300 K). The material was prepared by atomic layer deposition of ~2 nm thick TiO2 on millimeter-sized samples of np-Au (40–50 nm mean ligament size) and catalytically investigated with respect to aerobic CO oxidation. Moreover, the annealing-induced changes in catalytic activity are correlated with concurrent morphology and phase changes as provided by cross-sectional scanning electron microscopy, transmission electron microscopy, and near-edge X-ray absorption fine structure (NEXAFS) spectroscopy.« less

  19. Determination of redox reaction rates and orders by in-situ liquid cell electron microscopy of Pd and Au solution growth

    SciTech Connect (OSTI)

    Sutter, Eli A.; Sutter, Peter W.

    2014-11-19

    In-situ liquid cell transmission and scanning transmission electron microscopy (TEM/STEM) experiments are important as they provide direct insight into processes in liquids, such as solution growth of nanoparticles among others. In liquid cell TEM/STEM redox reaction experiments the hydrated electrons e?aq created by the electron beam are responsible for the reduction of metal-ion complexes. Here we investigate the rate equation of redox reactions involving reduction by e?aq generated by the electron beam during in-situ liquid TEM/STEM. Specifically we consider the growth of Pd on Au seeds in aqueous solutions containing Pd-chloro complexes. From the quantification of the rate of Pd deposition at different electron beam currents and as a function of distance from a stationary, nanometer-sized exciting beam, we determine that the reaction is first order with respect to the concentration of hydrated electrons, [e?aq]. By comparing Pd- and Au-deposition, we further demonstrate that measurements of the local deposition rate on nanoparticles in the solution via real-time imaging can be used to measure not only [e?aq] but also the rate of reduction of a metal-ion complex to zero-valent metal atoms in solution.

  20. Effects of electron recirculation on a hard x-ray source observed during the interaction of a high intensity laser pulse with thin Au targets

    SciTech Connect (OSTI)

    Compant La Fontaine, A.; Courtois, C.; Lefebvre, E.; Bourgade, J. L.; Landoas, O.; Thorp, K.; Stoeckl, C.

    2013-12-15

    The interaction of a high intensity laser pulse on the preplasma of a high-Z solid target produced by the pulse's pedestal generates high-energy electrons. These electrons subsequently penetrate inside the solid target and produce bremsstrahlung photons, generating an x-ray source which can be used for photonuclear studies or to radiograph high area density objects. The source characteristics are compared for targets with thin (20 μm) and thick (100 μm) Au foils on the Omega EP laser at Laboratory for Laser Energetics. Simulations using the particle-in-cell code CALDER show that for a 20 μm thickness Au target, electrons perform multiple round-trips in the target under the effect of the laser ponderomotive potential and the target electrostatic potential. These relativistic electrons have random transverse displacements, with respect to the target normal, attributed to electrostatic fluctuation fields. As a result, the x-ray spot size is increased by a factor 2 for thin target compared to thick targets, in agreement with experimental results. In addition, the computed doses agree with the measured ones provided that electron recirculation in the thin target is taken into account. A dose increase by a factor 1.7 is then computed by allowing for recirculation. In the 100 μm target case, on the other hand, this effect is found to be negligible.

  1. Sintered Cr/Pt and Ni/Au ohmic contacts to B12P2

    SciTech Connect (OSTI)

    Frye, Clint D.; Kucheyev, Sergei O.; Edgar, James H.; Voss, Lars F.; Conway, Adam M.; Shao, Qinghui; Nikolic, Rebecca J.

    2015-04-09

    With this study, icosahedral boron phosphide (B12P2) is a wide-bandgap semiconductor possessing interesting properties such as high hardness, chemical inertness, and the reported ability to self-heal from irradiation by high energy electrons. Here, the authors developed Cr/Pt and Ni/Au ohmic contacts to epitaxially grown B12P2 for materials characterization and electronic device development. Cr/Pt contacts became ohmic after annealing at 700 °C for 30 s with a specific contact resistance of 2×10–4 Ω cm2, as measured by the linear transfer length method. Ni/Au contacts were ohmic prior to any annealing, and their minimum specific contact resistance was ~l–4 × 10–4 Ω cm2 after annealing over the temperature range of 500–800 °C. Rutherford backscattering spectrometry revealed a strong reaction and intermixing between Cr/Pt and B12P2 at 700 °C and a reaction layer between Ni and B12P2 thinner than ~25 nm at 500 °C.

  2. Cross section for bb¯ production via dielectrons in d + Au collisions at sNN=200 GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adare, A.; Aidala, C.; Ajitanand, N. N.; Akiba, Y.; Al-Bataineh, H.; Alexander, J.; Angerami, A.; Aoki, K.; Apadula, N.; Aramaki, Y.; et al

    2015-01-26

    We report a measurement of e⁺e⁻ pairs from semileptonic heavy-flavor decays in d+Au collisions at √sNN = 200 GeV. Thus, exploring the mass and transverse-momentum dependence of the yield, the bottom decay contribution can be isolated from charm, and quantified by comparison to PYTHIA and MC@NLO simulations. The resulting bb-production cross section is σdAubb=1.37±0.28(stat)±0.46(syst) mb, which is equivalent to a nucleon-nucleon cross section of σNNbb =3.4 ± 0.8(stat)±1.1(syst) µb.

  3. Search for Charged Strange Quark Matter Produced in 11.5{ital A} GeV/{ital c} Au+Pb Collisions

    SciTech Connect (OSTI)

    De Cataldo, G.; Giglietto, N.; Raino, A.; Spinelli, P.; Huang, H.Z.; Hill, J.C.; Hoversten, R.A.; Libby, B.; Wohn, F.K.; Rabin, M.S.; Haridas, P.; Pless, I.A.; Van Buren, G.; Armstrong, T.A.; Lewis, R.A.; Reid, J.D.; Smith, G.A.; Toothacker, W.S.; Davies, R.; Hirsch, A.S.; Porile, N.T.; Rimai, A.; Scharenberg, R.P.; Srivastava, B.K.; Tincknell, M.L.; Lainis, T.; Greene, S.V.; Bennett, S.J.; Cormier, T.M.; Dee, P.; Fachini, P.; Kim, B.; Li, Q.; Munhoz, M.G.; Pruneau, C.A.; Wilson, W.K.; Zhao, K.; Barish, K.N.; Bennett, M.J.; Chikanian, A.; Coe, S.D.; Diebold, G.E.; Finch, L.E.; George, N.K.; Kumar, B.S.; Lajoie, J.G.; Majka, R.D.; Nagle, J.L.; Pope, J.K.; Rotondo, F.S.; Sandweiss, J.; Slaughter, A.J.; Wolin, E.J.; Xu, Z.

    1997-11-01

    We present results of a search for strange quark matter (strangelets) in 11.5A GeV /c Au+Pb collisions from the 1994 and 1995 runs of experiment E864 at Brookhaven{close_quote}s Alternating Gradient Synchrotron. We observe no strangelet candidates and set a 90{percent} confidence level upper limit of approximately 3{times}10{sup {minus}8} per 10{percent} central interaction for the production of {vert_bar}Z{vert_bar}=1 and {vert_bar}Z{vert_bar}=2 strangelets over a large mass range and with metastable lifetimes of about 50ns or more. These results place constraints primarily on quark-gluon plasma based production models for strangelets. {copyright} {ital 1997} {ital The American Physical Society}

  4. POST-CLOSURE INSPECTION REPORT FOR CORRECTIVE ACTION UNIT 333: U-3auS DISPOSAL SITE, NEVADA TEST SITE, NEVADA FOR THE PERIOD JULY 2005-JUNE 2006

    SciTech Connect (OSTI)

    2006-08-01

    Corrective Action Unit (CAU) 333, U-3auS Disposal Site, is a closed construction landfill located in Area 3 of the Nevada Test Site (NTS). The closure of this site was approved by the Nevada Division of Environmental Protection (NDEP) in a letter to the U.S. Department of Energy, National Nuclear Security Administration Nevada Operations Office (NNSA/NV) dated June 27, 2001. Post-closure requirements are described in a letter from NNSA/NV to NDEP dated October 9, 2001, and were approved by the NDEP in a letter dated November 5, 2001. This report covers the period July 2005 through June 2006 and consists of copies of the inspection checklist and field notes, repair records (if any), photographs, and recommendations and conclusions.

  5. Spin and orbital magnetism of coinage metal trimers (Cu{sub 3}, Ag{sub 3}, Au{sub 3}): A relativistic density functional theory study

    SciTech Connect (OSTI)

    Afshar, Mahdi; Sargolzaei, Mohsen

    2013-11-15

    We have demonstrated electronic structure and magnetic properties of Cu{sub 3}, Ag{sub 3} and Au{sub 3} trimers using a full potential local orbital method in the framework of relativistic density functional theory. We have also shown that the non-relativistic generalized gradient approximation for the exchange-correlation energy functional gives reliable magnetic properties in coinage metal trimers compared to experiment. In addition we have indicated that the spin-orbit coupling changes the structure and magnetic properties of gold trimer while the structure and magnetic properties of copper and silver trimers are marginally affected. A significant orbital moment of 0.21?{sub B} was found for most stable geometry of the gold trimer whereas orbital magnetism is almost quenched in the copper and silver trimers.

  6. Growth of GaN@InGaN Core-Shell and Au-GaN Hybrid Nanostructures for Energy Applications

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kuykendall, Tevye; Aloni, Shaul; Jen-La Plante, Ilan; Mokari, Taleb

    2009-01-01

    We demonstrated a method to control the bandgap energy of GaN nanowires by forming GaN@InGaN core-shell hybrid structures using metal organic chemical vapor deposition (MOCVD). Furthermore, we show the growth of Au nanoparticles on the surface of GaN nanowires in solution at room temperature. The work shown here is a first step toward engineering properties that are crucial for the rational design and synthesis of a new class of photocatalytic materials. The hybrid structures were characterized by various techniques, including photoluminescence (PL), energy dispersive x-ray spectroscopy (EDS), transmission and scanning electron microscopy (TEM and SEM), and x-ray diffraction (XRD).

  7. Effect of final state interactions on particle production in d+Au collisions at energies available at the BNL Relativistic Heavy Ion Collider

    SciTech Connect (OSTI)

    Zhang, X.; Xu, Z.; Chen, J.; Ren, Z.; Xu, N.; Zheng, Q.; and Zhu, X.

    2011-09-15

    We show that particle species dependence of enhanced hadron production at intermediate transverse momentum (p{sub T}) for d+Au collisions at RHIC can be understood in terms of the hadronization from string fragmentation and the subsequent hadronic rescatterings in the final state. A multiphase transport model (AMPT) with two different hadronization mechanisms, string fragmentation or parton coalescence, is used in our study. When the hadrons are formed from string fragmentation, the subsequent hadronic rescatterings will result in particle mass dependence of the nuclear modification factor R{sub CP}, which is consistent with the present experimental data. On the other hand, in the framework of parton coalescence, the mass dependence disappears and the strangeness plays an important role in hadron production.

  8. GROUND-BASED INFRARED DETECTIONS OF CO IN THE CENTAUR-COMET 29P/SCHWASSMANN-WACHMANN 1 AT 6.26 AU FROM THE SUN

    SciTech Connect (OSTI)

    Paganini, Lucas; Mumma, Michael J.; DiSanti, Michael A.; Villanueva, Geronimo L.; Bonev, Boncho P.; Boehnhardt, Hermann; Lippi, Manuela; Kaeufl, Hans U.; Blake, Geoffrey A.

    2013-04-01

    We observed Comet 29P/Schwassmann-Wachmann 1 (hereafter, 29P) in 2012 February and May with CRIRES/VLT and NIRSPEC/Keck-II, when the comet was at 6.26 AU from the Sun and about 5.50 AU from Earth. With CRIRES, we detected five CO emission lines on several nights in each epoch, confirming the ubiquitous content and release of carbon monoxide from the nucleus. This is the first simultaneous detection of multiple lines from any (neutral) gaseous species in comet 29P at infrared wavelengths. It is also the first extraction of a rotational temperature based on the intensities of simultaneously measured spectral lines in 29P, and the retrieved rotational temperature is the lowest obtained in our infrared survey to date. We present the retrieved production rates ({approx}3 Multiplication-Sign 10{sup 28} molecules s{sup -1}) and remarkably low ({approx}5 K) rotational temperatures for CO, and compare them with results from previous observations at radio wavelengths. Along with CO, we pursued detections of other volatiles, namely H{sub 2}O, C{sub 2}H{sub 6}, C{sub 2}H{sub 2}, CH{sub 4}, HCN, NH{sub 3}, and CH{sub 3}OH. Although they were not detected, we present sensitive upper limits. These results establish a new record for detections by infrared spectroscopy of parent volatiles in comets at large heliocentric distances. Until now considered to be a somewhat impossible task with IR ground-based facilities, these discoveries demonstrate new opportunities for targeting volatile species in distant comets.

  9. Influence of stellar multiplicity on planet formation. II. Planets are less common in multiple-star systems with separations smaller than 1500 AU

    SciTech Connect (OSTI)

    Wang, Ji; Fischer, Debra A.; Xie, Ji-Wei; Ciardi, David R.

    2014-08-20

    Almost half of the stellar systems in the solar neighborhood are made up of multiple stars. In multiple-star systems, planet formation is under the dynamical influence of stellar companions, and the planet occurrence rate is expected to be different from that of single stars. There have been numerous studies on the planet occurrence rate of single star systems. However, to fully understand planet formation, the planet occurrence rate in multiple-star systems needs to be addressed. In this work, we infer the planet occurrence rate in multiple-star systems by measuring the stellar multiplicity rate for planet host stars. For a subsample of 56 Kepler planet host stars, we use adaptive optics (AO) imaging and the radial velocity (RV) technique to search for stellar companions. The combination of these two techniques results in high search completeness for stellar companions. We detect 59 visual stellar companions to 25 planet host stars with AO data. Three stellar companions are within 2'' and 27 within 6''. We also detect two possible stellar companions (KOI 5 and KOI 69) showing long-term RV acceleration. After correcting for a bias against planet detection in multiple-star systems due to flux contamination, we find that planet formation is suppressed in multiple-star systems with separations smaller than 1500 AU. Specifically, we find that compared to single star systems, planets in multiple-star systems occur 4.5 3.2, 2.6 1.0, and 1.7 0.5 times less frequently when a stellar companion is present at a distance of 10, 100, and 1000 AU, respectively. This conclusion applies only to circumstellar planets; the planet occurrence rate for circumbinary planets requires further investigation.

  10. THE CHEMICAL COMPOSITION OF CO-RICH COMET C/2009 P1 (GARRADD) AT R{sub h} = 2.4 and 2.0 AU BEFORE PERIHELION

    SciTech Connect (OSTI)

    Paganini, L.; Mumma, M. J.; Villanueva, G. L.; DiSanti, M. A.; Bonev, B. P.; Lippi, M.; Boehnhardt, H.

    2012-03-20

    We quantified 10 parent volatiles in comet C/2009 P1 (Garradd) before perihelion, through high-dispersion infrared spectra acquired with CRIRES at ESO's Very Large Telescope on UT 2011 August 7 (R{sub h} = 2.4 AU) and September 17-21 (R{sub h} = 2.0 AU). On August 7, water was searched for but not detected at an upper limit (3{sigma}) of 2.1 Multiplication-Sign 10{sup 28} s{sup -1}, while ethane was detected with a production rate of 6.1 Multiplication-Sign 10{sup 26} s{sup -1}. On September 17-21, the mean production rate for water was 8.4 Multiplication-Sign 10{sup 28} s{sup -1}, and five trace species (CO, C{sub 2}H{sub 6}, CH{sub 4}, HCN, and CH, OH) were securely detected, and (3{sigma}) upper limits were retrieved for NH{sub 3}, C{sub 2}H{sub 2}, OCS, and HDO. Given the relatively large heliocentric distance, we explored the effect of water not being fully sublimated within our field of view and identified the 'missing' water fraction needed to reconcile the retrieved abundance ratios with the mean values found for 'organics-normal' comets. The individual spatial profiles of parent volatiles and the continuum displayed rather asymmetric outgassing. Indications of H{sub 2}O and CO gas being released in different directions suggest chemically distinct active vents and/or the possible existence of polar and apolar ice aggregates in the nucleus. The high fractional abundance of CO identifies comet C/2009 P1 as a CO-rich comet.

  11. Phosphine-stabilised Au{sub 9} clusters interacting with titania and silica surfaces: The first evidence for the density of states signature of the support-immobilised cluster

    SciTech Connect (OSTI)

    Andersson, Gunther G. E-mail: vladimir.golovko@canterbury.ac.nz Al Qahtani, Hassan S.; Golovko, Vladimir B. E-mail: vladimir.golovko@canterbury.ac.nz; Alvino, Jason F.; Bennett, Trystan; Wrede, Oliver; Mejia, Sol M.; Metha, Gregory F. E-mail: vladimir.golovko@canterbury.ac.nz; Adnan, Rohul; Gunby, Nathaniel; Anderson, David P.

    2014-07-07

    Chemically made, atomically precise phosphine-stabilized clusters Au{sub 9}(PPh{sub 3}){sub 8}(NO{sub 3}){sub 3} were deposited on titania and silica from solutions at various concentrations and the samples heated under vacuum to remove the ligands. Metastable induced electron spectroscopy was used to determine the density of states at the surface, and X-ray photoelectron spectroscopy for analysing the composition of the surface. It was found for the Au{sub 9} cluster deposited on titania that the ligands react with the titania substrate. Based on analysis using the singular value decomposition algorithm, the series of MIE spectra can be described as a linear combination of 3 base spectra that are assigned to the spectra of the substrate, the phosphine ligands on the substrate, and the Au clusters anchored to titania after removal of the ligands. On silica, the Au clusters show significant agglomeration after heat treatment and no interaction of the ligands with the substrate can be identified.

  12. Decay of the 9/2{sup -} isomer in {sup 181}Tl and mass determination of low-lying states in {sup 181}Tl, {sup 177}Au, and {sup 173}Ir

    SciTech Connect (OSTI)

    Andreyev, A. N.; Antalic, S.; Saro, S.; Ackermann, D.; Comas, V. F.; Heinz, S.; Heredia, J. A.; Hessberger, F. P.; Khuyagbaatar, J.; Kojouharov, I.; Kindler, B.; Lommel, B.; Mann, R.; Cocolios, T. E.; Elseviers, J.; Huyse, M.; Van Duppen, P. Van; Venhart, M.; Franchoo, S.; Hofmann, S.

    2009-08-15

    A detailed spectroscopic study of the neutron-deficient isotope {sup 181}Tl and the daughter of its {alpha} decay, {sup 177}Au, has been performed in the complete fusion reaction {sup 40}Ca+{sup 144}Sm{yields}{sup 184}Pb* at the velocity filter SHIP (GSI). The mass excess, excitation energy, and decay scheme of the isomeric 1.40(3) ms, 9/2{sup -} intruder state in {sup 181}Tl have been established for the first time. These results solve a long-standing puzzle of the unrealistically large reduced {alpha}-decay width of this isomer. Based on this, the previously unknown masses of the long-lived isomeric states in {sup 177}Au and {sup 173}Ir have been derived. In turn, it now allows the excitation energies of previously identified bands in {sup 177}Au and {sup 173}Ir to be deduced and compared with theoretical predictions. First measurements of {alpha}-decay branching ratios for {sup 181}Tl{sup m} and {sup 177}Au{sup m,g} are also reported.

  13. Charged-to-neutral correlation at forward rapidity in Au+Au collisions at sNN=200 GeV

    SciTech Connect (OSTI)

    Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alekseev, I.; Alford, J.; Anson, C. D.; Aparin, A.; Arkhipkin, D.; Aschenauer, E. C.; Averichev, G. S.; Banerjee, A.; Beavis, D. R.; Bellwied, R.; Bhasin, A.; Bhati, A. K.; Bhattarai, P.; Bichsel, H.; Bielcik, J.; Bielcikova, J.; Bland, L. C.; Bordyuzhin, I. G.; Borowski, W.; Bouchet, J.; Brandin, A. V.; Brovko, S. G.; Bltmann, S.; Bunzarov, I.; Burton, T. P.; Butterworth, J.; Caines, H.; Caldern de la Barca Snchez, M.; Campbell, J. M.; Cebra, D.; Cendejas, R.; Cervantes, M. C.; Chaloupka, P.; Chang, Z.; Chattopadhyay, S.; Chen, H. F.; Chen, J. H.; Chen, L.; Cheng, J.; Cherney, M.; Chikanian, A.; Christie, W.; Chwastowski, J.; Codrington, M. J. M.; Contin, G.; Cramer, J. G.; Crawford, H. J.; Cui, X.; Das, S.; Davila Leyva, A.; De Silva, L. C.; Debbe, R. R.; Dedovich, T. G.; Deng, J.; Derevschikov, A. A.; Derradi de Souza, R.; di Ruzza, B.; Didenko, L.; Dilks, C.; Ding, F.; Djawotho, P.; Dong, X.; Drachenberg, J. L.; Draper, J. E.; Du, C. M.; Dunkelberger, L. E.; Dunlop, J. C.; Efimov, L. G.; Engelage, J.; Engle, K. S.; Eppley, G.; Eun, L.; Evdokimov, O.; Eyser, O.; Fatemi, R.; Fazio, S.; Fedorisin, J.; Filip, P.; Fisyak, Y.; Flores, C. E.; Gagliardi, C. A.; Gangadharan, D. R.; Garand, D.; Geurts, F.; Gibson, A.; Girard, M.; Gliske, S.; Greiner, L.; Grosnick, D.; Gunarathne, D. S.; Guo, Y.; Gupta, A.; Gupta, S.; Guryn, W.; Haag, B.; Hamed, A.; Han, L-X.; Haque, R.; Harris, J. W.; Heppelmann, S.; Hirsch, A.; Hoffmann, G. W.; Hofman, D. J.; Horvat, S.; Huang, B.; Huang, H. Z.; Huang, X.; Huck, P.; Humanic, T. J.; Igo, G.; Jacobs, W. W.; Jang, H.; Judd, E. G.; Kabana, S.; Kalinkin, D.; Kang, K.; Kauder, K.; Ke, H. W.; Keane, D.; Kechechyan, A.; Kesich, A.; Khan, Z. H.; Kikola, D. P.; Kisel, I.; Kisiel, A.; Koetke, D. D.; Kollegger, T.; Konzer, J.; Koralt, I.; Kosarzewski, L. K.; Kotchenda, L.; Kraishan, A. F.; Kravtsov, P.; Krueger, K.; Kulakov, I.; Kumar, L.; Kycia, R. A.; Lamont, M. A. C.; Landgraf, J. M.; Landry, K. D.; Lauret, J.; Lebedev, A.; Lednicky, R.; Lee, J. H.; Li, C.; Li, W.; Li, X.; Li, X.; Li, Y.; Li, Z. M.; Lisa, M. A.; Liu, F.; Ljubicic, T.; Llope, W. J.; Lomnitz, M.; Longacre, R. S.; Luo, X.; Ma, G. L.; Ma, Y. G.; Mahapatra, D. P.; Majka, R.; Margetis, S.; Markert, C.; Masui, H.; Matis, H. S.; McDonald, D.; McShane, T. S.; Minaev, N. G.; Mioduszewski, S.; Mohanty, B.; Mondal, M. M.; Morozov, D. A.; Mustafa, M. K.; Nandi, B. K.; Nasim, Md.; Nayak, T. K.; Nelson, J. M.; Nigmatkulov, G.; Nogach, L. V.; Noh, S. Y.; Novak, J.; Nurushev, S. B.; Odyniec, G.; Ogawa, A.; Oh, K.; Ohlson, A.; Okorokov, V.; Oldag, E. W.; Olvitt, D. L.; Page, B. S.; Pan, Y. X.; Pandit, Y.; Panebratsev, Y.; Pawlak, T.; Pawlik, B.; Pei, H.; Perkins, C.; Pile, P.; Planinic, M.; Pluta, J.; Poljak, N.; Poniatowska, K.; Porter, J.; Poskanzer, A. M.; Pruthi, N. K.; Przybycien, M.; Putschke, J.; Qiu, H.; Quintero, A.; Ramachandran, S.; Raniwala, R.; Raniwala, S.; Ray, R. L.; Riley, C. K.; Ritter, H. G.; Roberts, J. B.; Rogachevskiy, O. V.; Romero, J. L.; Ross, J. F.; Roy, A.; Ruan, L.; Rusnak, J.; Rusnakova, O.; Sahoo, N. R.; Sahu, P. K.; Sakrejda, I.; Salur, S.; Sandacz, A.; Sandweiss, J.; Sangaline, E.; Sarkar, A.; Schambach, J.; Scharenberg, R. P.; Schmah, A. M.; Schmidke, W. B.; Schmitz, N.; Seger, J.; Seyboth, P.; Shah, N.; Shahaliev, E.; Shanmuganathan, P. V.; Shao, M.; Sharma, B.; Shen, W. Q.; Shi, S. S.; Shou, Q. Y.; Sichtermann, E. P.; Simko, M.; Skoby, M. J.; Smirnov, D.; Smirnov, N.; Solanki, D.; Sorensen, P.; Spinka, H. M.; Srivastava, B.; Stanislaus, T. D. S.; Stevens, J. R.; Stock, R.; Strikhanov, M.; Stringfellow, B.; Sumbera, M.; Sun, X.; Sun, X. M.; Sun, Y.; Sun, Z.; Surrow, B.; Svirida, D. N.; Symons, T. J. M.; Szelezniak, M. A.; Takahashi, J.; Tang, A. H.; Tang, Z.; Tarnowsky, T.; Thomas, J. H.; Timmins, A. R.; Tlusty, D.; Tokarev, M.; Trentalange, S.; Tribble, R. E.; Tribedy, P.; Trzeciak, B. A.; Tsai, O. D.; Turnau, J.; Ullrich, T.; Underwood, D. G.; Van Buren, G.; van Nieuwenhuizen, G.; Vandenbroucke, M.; Vanfossen, J. A.; Varma, R.; Vasconcelos, G. M. S.; Vasiliev, A. N.; Vertesi, R.; Videbk, F.; Viyogi, Y. P.; Vokal, S.; Vossen, A.; Wada, M.; Wang, F.; Wang, G.; Wang, H.; Wang, J. S.; Wang, X. L.; Wang, Y.; Wang, Y.; Webb, G.; Webb, J. C.; Westfall, G. D.; Wieman, H.; Wissink, S. W.; Witt, R.; Wu, Y. F.; Xiao, Z.; Xie, W.; Xin, K.; Xu, H.; Xu, J.; Xu, N.; Xu, Q. H.; Xu, Y.; Xu, Z.; Yan, W.; Yang, C.; Yang, Y.; Yang, Y.; Ye, Z.; Yepes, P.; Yi, L.; Yip, K.; Yoo, I-K.; Yu, N.; Zbroszczyk, H.; Zha, W.; Zhang, J. B.; Zhang, J. L.; Zhang, S.; Zhang, X. P.; Zhang, Y.; Zhang, Z. P.; Zhao, F.; Zhao, J.; Zhong, C.; Zhu, X.; Zhu, Y. H.; Zoulkarneeva, Y.; Zyzak, M.

    2015-03-20

    Event-by-event fluctuations of the ratio of inclusive charged to photon multiplicities at forward rapidity in Au+Au collision at ?sNN=200 GeV have been studied. Dominant contribution to such fluctuations is expected to come from correlated production of charged and neutral pions. We search for evidences of dynamical fluctuations of different physical origins. Observables constructed out of moments of multiplicities are used as measures of fluctuations. Mixed events and model calculations are used as baselines. Results are compared to the dynamical net-charge fluctuations measured in the same acceptance. A non-zero statistically significant signal of dynamical fluctuations is observed in excess to the model prediction when charged particles and photons are measured in the same acceptance. Thus, we find that, unlike dynamical net-charge fluctuation, charge-neutral fluctuation is not dominated by correlation due to particle decay. Results are compared to the expectations based on the generic production mechanism of pions due to isospin symmetry, for which no significant (< 1%) deviation is observed.

  14. Centrality dependence of low-momentum direct-photon production in Au+Au collisions at sNN=200 GeV

    SciTech Connect (OSTI)

    Adare, A.; Afanasiev, S.; Aidala, C.; Ajitanand, N. N.; Akiba, Y.; Akimoto, R.; Al-Bataineh, H.; Al-Ta'ani, H.; Alexander, J.; Angerami, A.; Aoki, K.; Apadula, N.; Aramaki, Y.; Asano, H.; Aschenauer, E. C.; Atomssa, E. T.; Averbeck, R.; Awes, T. C.; Azmoun, B.; Babintsev, V.; Bai, M.; Baksay, G.; Baksay, L.; Bannier, B.; Barish, K. N.; Bassalleck, B.; Basye, A. T.; Bathe, S.; Baublis, V.; Baumann, C.; Baumgart, S.; Bazilevsky, A.; Belikov, S.; Belmont, R.; Bennett, R.; Berdnikov, A.; Berdnikov, Y.; Bickley, A. A.; Bing, X.; Blau, D. S.; Bok, J. S.; Boyle, K.; Brooks, M. L.; Buesching, H.; Bumazhnov, V.; Bunce, G.; Butsyk, S.; Camacho, C. M.; Campbell, S.; Castera, P.; Chen, C. -H.; Chi, C. Y.; Chiu, M.; Choi, I. J.; Choi, J. B.; Choi, S.; Choudhury, R. K.; Christiansen, P.; Chujo, T.; Chung, P.; Chvala, O.; Cianciolo, V.; Citron, Z.; Cole, B. A.; Connors, M.; Constantin, P.; Csanád, M.; Csörgő, T.; Dahms, T.; Dairaku, S.; Danchev, I.; Das, K.; Datta, A.; Daugherity, M. S.; David, G.; Denisov, A.; Deshpande, A.; Desmond, E. J.; Dharmawardane, K. V.; Dietzsch, O.; Ding, L.; Dion, A.; Donadelli, M.; Drapier, O.; Drees, A.; Drees, K. A.; Durham, J. M.; Durum, A.; Dutta, D.; D'Orazio, L.; Edwards, S.; Efremenko, Y. V.; Ellinghaus, F.; Engelmore, T.; Enokizono, A.; En'yo, H.; Esumi, S.; Eyser, K. O.; Fadem, B.; Fields, D. E.; Finger, M.; Finger, M.; Fleuret, F.; Fokin, S. L.; Fraenkel, Z.; Frantz, J. E.; Franz, A.; Frawley, A. D.; Fujiwara, K.; Fukao, Y.; Fusayasu, T.; Gainey, K.; Gal, C.; Garishvili, A.; Garishvili, I.; Glenn, A.; Gong, H.; Gong, X.; Gonin, M.; Goto, Y.; Granier de Cassagnac, R.; Grau, N.; Greene, S. V.; Grosse Perdekamp, M.; Gunji, T.; Guo, L.; Gustafsson, H. -Å.; Hachiya, T.; Haggerty, J. S.; Hahn, K. I.; Hamagaki, H.; Hamblen, J.; Han, R.; Hanks, J.; Hartouni, E. P.; Hashimoto, K.; Haslum, E.; Hayano, R.; He, X.; Heffner, M.; Hemmick, T. K.; Hester, T.; Hill, J. C.; Hohlmann, M.; Hollis, R. S.; Holzmann, W.; Homma, K.; Hong, B.; Horaguchi, T.; Hori, Y.; Hornback, D.; Huang, S.; Ichihara, T.; Ichimiya, R.; Ide, J.; Iinuma, H.; Ikeda, Y.; Imai, K.; Imrek, J.; Inaba, M.; Iordanova, A.; Isenhower, D.; Ishihara, M.; Isobe, T.; Issah, M.; Isupov, A.; Ivanischev, D.; Ivanishchev, D.; Jacak, B. V.; Javani, M.; Jia, J.; Jiang, X.; Jin, J.; Johnson, B. M.; Joo, K. S.; Jouan, D.; Jumper, D. S.; Kajihara, F.; Kametani, S.; Kamihara, N.; Kamin, J.; Kaneti, S.; Kang, B. H.; Kang, J. H.; Kang, J. S.; Kapustinsky, J.; Karatsu, K.; Kasai, M.; Kawall, D.; Kawashima, M.; Kazantsev, A. V.; Kempel, T.; Khanzadeev, A.; Kijima, K. M.; Kim, B. I.; Kim, C.; Kim, D. H.; Kim, D. J.; Kim, E.; Kim, E. -J.; Kim, H. J.; Kim, K. -B.; Kim, S. H.; Kim, Y. -J.; Kim, Y. K.; Kinney, E.; Kiriluk, K.; Kiss, Á.; Kistenev, E.; Klatsky, J.; Kleinjan, D.; Kline, P.; Kochenda, L.; Komatsu, Y.; Komkov, B.; Konno, M.; Koster, J.; Kotchetkov, D.; Kotov, D.; Kozlov, A.; Král, A.; Kravitz, A.; Krizek, F.; Kunde, G. J.; Kurita, K.; Kurosawa, M.; Kwon, Y.; Kyle, G. S.; Lacey, R.; Lai, Y. S.; Lajoie, J. G.; Lebedev, A.; Lee, B.; Lee, D. M.; Lee, J.; Lee, K.; Lee, K. B.; Lee, K. S.; Lee, S. H.; Lee, S. R.; Leitch, M. J.; Leite, M. A. L.; Leitgab, M.; Leitner, E.; Lenzi, B.; Lewis, B.; Li, X.; Liebing, P.; Lim, S. H.; Linden Levy, L. A.; Liška, T.; Litvinenko, A.; Liu, H.; Liu, M. X.; Love, B.; Luechtenborg, R.; Lynch, D.; Maguire, C. F.; Makdisi, Y. I.; Makek, M.; Malakhov, A.; Malik, M. D.; Manion, A.; Manko, V. I.; Mannel, E.; Mao, Y.; Masui, H.; Masumoto, S.; Matathias, F.; McCumber, M.; McGaughey, P. L.; McGlinchey, D.; McKinney, C.; Means, N.; Mendoza, M.; Meredith, B.; Miake, Y.; Mibe, T.; Mignerey, A. C.; Mikeš, P.; Miki, K.; Milov, A.; Mishra, D. K.; Mishra, M.; Mitchell, J. T.; Miyachi, Y.; Miyasaka, S.; Mohanty, A. K.; Moon, H. J.; Morino, Y.; Morreale, A.; Morrison, D. P.; Motschwiller, S.; Moukhanova, T. V.; Murakami, T.; Murata, J.; Nagae, T.; Nagamiya, S.; Nagle, J. L.; Naglis, M.; Nagy, M. I.; Nakagawa, I.; Nakamiya, Y.; Nakamura, K. R.; Nakamura, T.; Nakano, K.; Nattrass, C.; Nederlof, A.; Newby, J.; Nguyen, M.; Nihashi, M.; Nouicer, R.; Novitzky, N.; Nyanin, A. S.; O'Brien, E.; Oda, S. X.; Ogilvie, C. A.; Oka, M.; Okada, K.; Onuki, Y.; Oskarsson, A.; Ouchida, M.; Ozawa, K.; Pak, R.; Pantuev, V.; Papavassiliou, V.; Park, B. H.; Park, I. H.; Park, J.; Park, S. K.; Park, W. J.; Pate, S. F.; Patel, L.; Pei, H.; Peng, J. -C.; Pereira, H.; Peresedov, V.; Peressounko, D. Yu.; Petti, R.; Pinkenburg, C.; Pisani, R. P.; Proissl, M.; Purschke, M. L.; Purwar, A. K.; Qu, H.; Rak, J.; Rakotozafindrabe, A.; Ravinovich, I.; Read, K. F.; Reygers, K.; Reynolds, D.; Riabov, V.; Riabov, Y.; Richardson, E.; Riveli, N.; Roach, D.; Roche, G.; Rolnick, S. D.; Rosati, M.; Rosen, C. A.; Rosendahl, S. S. E.; Rosnet, P.; Rukoyatkin, P.; Ružička, P.; Sahlmueller, B.; Saito, N.; Sakaguchi, T.; Sakashita, K.; Samsonov, V.; Sano, M.; Sano, S.; Sarsour, M.; Sato, T.; Sawada, S.; Sedgwick, K.; Seele, J.; Seidl, R.; Semenov, A. Yu.; Sen, A.; Seto, R.; Sharma, D.; Shein, I.; Shibata, T. -A.; Shigaki, K.; Shimomura, M.; Shoji, K.; Shukla, P.; Sickles, A.; Silva, C. L.; Silvermyr, D.; Silvestre, C.; Sim, K. S.; Singh, B. K.; Singh, C. P.; Singh, V.; Slunečka, M.; Soltz, R. A.; Sondheim, W. E.; Sorensen, S. P.; Soumya, M.; Sourikova, I. V.; Sparks, N. A.; Stankus, P. W.; Stenlund, E.; Stepanov, M.; Ster, A.; Stoll, S. P.; Sugitate, T.; Sukhanov, A.; Sun, J.; Sziklai, J.; Takagui, E. M.; Takahara, A.; Taketani, A.; Tanabe, R.; Tanaka, Y.; Taneja, S.; Tanida, K.; Tannenbaum, M. J.; Tarafdar, S.; Taranenko, A.; Tarján, P.; Tennant, E.; Themann, H.; Thomas, T. L.; Todoroki, T.; Togawa, M.; Toia, A.; Tomášek, L.; Tomášek, M.; Torii, H.; Towell, R. S.; Tserruya, I.; Tsuchimoto, Y.; Tsuji, T.; Vale, C.; Valle, H.; van Hecke, H. W.; Vargyas, M.; Vazquez-Zambrano, E.; Veicht, A.; Velkovska, J.; Vértesi, R.; Vinogradov, A. A.; Virius, M.; Vossen, A.; Vrba, V.; Vznuzdaev, E.; Wang, X. R.; Watanabe, D.; Watanabe, K.; Watanabe, Y.; Watanabe, Y. S.; Wei, F.; Wei, R.; Wessels, J.; Whitaker, S.; White, S. N.; Winter, D.; Wolin, S.; Wood, J. P.; Woody, C. L.; Wright, R. M.; Wysocki, M.; Xie, W.; Yamaguchi, Y. L.; Yamaura, K.; Yang, R.; Yanovich, A.; Ying, J.; Yokkaichi, S.; You, Z.; Young, G. R.; Younus, I.; Yushmanov, I. E.; Zajc, W. A.; Zelenski, A.; Zhang, C.; Zhou, S.; Zolin, L.

    2015-06-05

    The PHENIX experiment at RHIC has measured the centrality dependence of the direct photon yield from Au+Au collisions at √sNN = 200 GeV down to pT = 0.4 GeV/c. Photons are detected via photon conversions to e⁺e⁻ pairs and an improved technique is applied that minimizes the systematic uncertainties that usually limit direct photon measurements, in particular at low pT . We find an excess of direct photons above the Ncoll-scaled yield measured in p+p collisions. This excess yield is well described by an exponential distribution with an inverse slope of about 240 MeV/c in the pT range from 0.6–2.0 GeV/c. In this study, while the shape of the pT distribution is independent of centrality within the experimental uncertainties, the yield increases rapidly with increasing centrality, scaling approximately with N α part, where α = 1.38±0.03(stat)±0.07(syst).

  15. Multishell Au/Ag/SiO2 nanorods with tunable optical properties as single particle orientation and rotational tracking probes

    SciTech Connect (OSTI)

    Chen, Kuangcai; Lin, Chia -Cheng; Vela, Javier; Fang, Ning

    2015-04-07

    In this study, three-layer coreshell plasmonic nanorods (Au/Ag/SiO2NRs), consisting of a gold nanorod core, a thin silver shell, and a thin silica layer, were synthesized and used as optical imaging probes under a differential interference contrast microscope for single particle orientation and rotational tracking. The localized surface plasmon resonance modes were enhanced upon the addition of the silver shell, and the anisotropic optical properties of gold nanorods were maintained. The silica coating enables surface functionalization with silane coupling agents and provides enhanced stability and biocompatibility. Taking advantage of the longitudinal LSPR enhancement, the orientation and rotational information of the hybrid nanorods on synthetic lipid bilayers and on live cell membranes were obtained with millisecond temporal resolution using a scientific complementary metal-oxide-semiconductor camera. The results demonstrate that the as-synthesized hybrid nanorods are promising imaging probes with improved sensitivity and good biocompatibility for single plasmonic particle tracking experiments in biological systems.

  16. Investigation of the deposition and thermal behavior of striped phases of unsymmetric disulfide self-assembled monolayers on Au(111): The case of 11-hydroxyundecyl decyl disulfide

    SciTech Connect (OSTI)

    Albayrak, Erol; Karabuga, Semistan; Bracco, Gianangelo; Dan??man, M. Fatih

    2015-01-07

    Self-assembled monolayers (SAMs) of unsymmetric disulfides on Au(111) are used to form mixed SAMs that can be utilized in many applications. Here, we have studied 11-hydroxyundecyl decyl disulfide (CH{sub 3}(CH{sub 2}){sub 9}SS(CH{sub 2}){sub 11}OH, HDD) SAMs produced by supersonic molecular beam deposition and characterized by He diffraction. The film growth was monitored at different temperatures up to a coverage which corresponds to a full lying down phase and the diffraction analysis shows that below 250 K the phase is different from the phase measured above 300 K. During the annealing of the film, two phase transitions were observed, at 250 K and 350 K. The overall data suggest that the former is related to an irreversible phase separation of HDD above 250 K to decanethiolate (S(CH{sub 2}){sub 9}CH{sub 3}, DTT) and hydroxyundecylthiolate (S(CH{sub 2}){sub 11}OH, MUDT), while the latter to a reversible melting of the film. Above 450 K, the specular intensity shows an increase related to film desorption and different chemisorbed states were observed with energies in the same range as observed for decanethiol (HS(CH{sub 2}){sub 9}CH{sub 3}, DT) and mercaptoundecanol (HS(CH{sub 2}){sub 11}OH, MUD) SAMs.

  17. SUN-TO-EARTH CHARACTERISTICS OF TWO CORONAL MASS EJECTIONS INTERACTING NEAR 1 AU: FORMATION OF A COMPLEX EJECTA AND GENERATION OF A TWO-STEP GEOMAGNETIC STORM

    SciTech Connect (OSTI)

    Liu, Ying D.; Yang, Zhongwei; Wang, Rui; Luhmann, Janet G.; Richardson, John D.; Lugaz, Noé

    2014-10-01

    On 2012 September 30-October 1 the Earth underwent a two-step geomagnetic storm. We examine the Sun-to-Earth characteristics of the coronal mass ejections (CMEs) responsible for the geomagnetic storm with combined heliospheric imaging and in situ observations. The first CME, which occurred on 2012 September 25, is a slow event and shows an acceleration followed by a nearly invariant speed in the whole Sun-Earth space. The second event, launched from the Sun on 2012 September 27, exhibits a quick acceleration, then a rapid deceleration, and finally a nearly constant speed, a typical Sun-to-Earth propagation profile for fast CMEs. These two CMEs interacted near 1 AU as predicted by the heliospheric imaging observations and formed a complex ejecta observed at Wind, with a shock inside that enhanced the pre-existing southward magnetic field. Reconstruction of the complex ejecta with the in situ data indicates an overall left-handed flux-rope-like configuration with an embedded concave-outward shock front, a maximum magnetic field strength deviating from the flux rope axis, and convex-outward field lines ahead of the shock. While the reconstruction results are consistent with the picture of CME-CME interactions, a magnetic cloud-like structure without clear signs of CME interactions is anticipated when the merging process is finished.

  18. INTERVALS OF RADIAL INTERPLANETARY MAGNETIC FIELDS AT 1 AU, THEIR ASSOCIATION WITH RAREFACTION REGIONS, AND THEIR APPARENT MAGNETIC FOOT POINTS AT THE SUN

    SciTech Connect (OSTI)

    Orlove, Steven T.; Smith, Charles W.; Vasquez, Bernard J.; Schwadron, Nathan A.; Skoug, Ruth M.; Zurbuchen, Thomas H.; Zhao Liang E-mail: Charles.Smith@unh.edu E-mail: N.Schwadron@unh.edu E-mail: thomasz@umich.edu

    2013-09-01

    We have examined 226 intervals of nearly radial interplanetary magnetic field orientations at 1 AU lasting in excess of 6 hr. They are found within rarefaction regions as are the previously reported high-latitude observations. We show that these rarefactions typically do not involve high-speed wind such as that seen by Ulysses at high latitudes during solar minimum. We have examined both the wind speeds and the thermal ion composition before, during and after the rarefaction in an effort to establish the source of the flow that leads to the formation of the rarefaction. We find that the bulk of the measurements, both fast- and slow-wind intervals, possess both wind speeds and thermal ion compositions that suggest they come from typical low-latitude sources that are nominally considered slow-wind sources. In other words, we find relatively little evidence of polar coronal hole sources even when we examine the faster wind ahead of the rarefaction regions. While this is in contrast to high-latitude observations, we argue that this is to be expected of low-latitude observations where polar coronal hole sources are less prevalent. As with the previous high-latitude observations, we contend that the best explanation for these periods of radial magnetic field is interchange reconnection between two sources of different wind speed.

  19. Absolute radiant power measurement for the Au M lines of laser-plasma using a calibrated broadband soft X-ray spectrometer with flat-spectral response

    SciTech Connect (OSTI)

    Troussel, Ph.; Villette, B.; Oudot, G.; Tassin, V.; Bridou, F.; Delmotte, F.; Krumrey, M.

    2014-01-15

    CEA implemented an absolutely calibrated broadband soft X-ray spectrometer called DMX on the Omega laser facility at the Laboratory for Laser Energetics (LLE) in 1999 to measure radiant power and spectral distribution of the radiation of the Au plasma. The DMX spectrometer is composed of 20 channels covering the spectral range from 50 eV to 20 keV. The channels for energies below 1.5 keV combine a mirror and a filter with a coaxial photo-emissive detector. For the channels above 5 keV the photoemissive detector is replaced by a conductive detector. The intermediate energy channels (1.5 keV < photon energy < 5 keV) use only a filter and a coaxial detector. A further improvement of DMX consists in flat-response X-ray channels for a precise absolute measurement of the photon flux in the photon energy range from 0.1 keV to 6 keV. Such channels are equipped with a filter, a Multilayer Mirror (MLM), and a coaxial detector. We present as an example the development of channel for the gold M emission lines in the photon energy range from 2 keV to 4 keV which has been successfully used on the OMEGA laser facility. The results of the radiant power measurements with the new MLM channel and with the usual channel composed of a thin titanium filter and a coaxial detector (without mirror) are compared. All elements of the channel have been calibrated in the laboratory of the Physikalisch-Technische Bundesanstalt, Germany's National Metrology Institute, at the synchrotron radiation facility BESSY II in Berlin using dedicated well established and validated methods.

  20. SISGR-MuSR Investigations of Magnetic Semiconductors for Spintronics...

    Office of Scientific and Technical Information (OSTI)

    Research Org: Texas Tech University Sponsoring Org: USDOE Country of Publication: United States Language: English Word Cloud More Like This Full Text preview image File size N...

  1. SISGR-MuSR Investigations of Magnetic Semiconductors for Spintronics...

    Office of Scientific and Technical Information (OSTI)

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  2. Measurements of dielectron production in Au + Au collisions at sNN=200 GeV from the STAR experiment

    SciTech Connect (OSTI)

    Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alekseev, I.; Alford, J.; Aparin, A.; Arkhipkin, D.; Aschenauer, E. C.; Averichev, G. S.; Banerjee, A.; Bellwied, R.; Bhasin, A.; Bhati, A. K.; Bhattarai, P.; Bielcik, J.; Bielcikova, J.; Bland, L. C.; Bordyuzhin, I. G.; Bouchet, J.; Brandin, A. V.; Bunzarov, I.; Burton, T. P.; Butterworth, J.; Caines, H.; Calderón de la Barca Sánchez, M.; Campbell, J. M.; Cebra, D.; Cervantes, M. C.; Chakaberia, I.; Chaloupka, P.; Chang, Z.; Chattopadhyay, S.; Chen, J. H.; Chen, X.; Cheng, J.; Cherney, M.; Christie, W.; Contin, G.; Crawford, H. J.; Das, S.; De Silva, L. C.; Debbe, R. R.; Dedovich, T. G.; Deng, J.; Derevschikov, A. A.; di Ruzza, B.; Didenko, L.; Dilks, C.; Dong, X.; Drachenberg, J. L.; Draper, J. E.; Du, C. M.; Dunkelberger, L. E.; Dunlop, J. C.; Efimov, L. G.; Engelage, J.; Eppley, G.; Esha, R.; Evdokimov, O.; Eyser, O.; Fatemi, R.; Fazio, S.; Federic, P.; Fedorisin, J.; Feng, Z.; Filip, P.; Fisyak, Y.; Flores, C. E.; Fulek, L.; Gagliardi, C. A.; Garand, D.; Geurts, F.; Gibson, A.; Girard, M.; Greiner, L.; Grosnick, D.; Gunarathne, D. S.; Guo, Y.; Gupta, S.; Gupta, A.; Guryn, W.; Hamad, A.; Hamed, A.; Haque, R.; Harris, J. W.; He, L.; Heppelmann, S.; Heppelmann, S.; Hirsch, A.; Hoffmann, G. W.; Hofman, D. J.; Horvat, S.; Huang, B.; Huang, X.; Huang, H. Z.; Huck, P.; Humanic, T. J.; Igo, G.; Jacobs, W. W.; Jang, H.; Jiang, K.; Judd, E. G.; Jung, K.; Kabana, S.; Kalinkin, D.; Kang, K.; Kauder, K.; Ke, H. W.; Keane, D.; Kechechyan, A.; Khan, Z. H.; Kikola, D. P.; Kisel, I.; Kisiel, A.; Kochenda, L.; Koetke, D. D.; Kollegger, T.; Kosarzewski, L. K.; Kraishan, A. F.; Kravtsov, P.; Krueger, K.; Kulakov, I.; Kumar, L.; Kycia, R. A.; Lamont, M. A. C.; Landgraf, J. M.; Landry, K. D.; Lauret, J.; Lebedev, A.; Lednicky, R.; Lee, J. H.; Li, X.; Li, C.; Li, W.; Li, Z. M.; Li, Y.; Li, X.; Lisa, M. A.; Liu, F.; Ljubicic, T.; Llope, W. J.; Lomnitz, M.; Longacre, R. S.; Luo, X.; Ma, Y. G.; Ma, G. L.; Ma, L.; Ma, R.; Magdy, N.; Majka, R.; Manion, A.; Margetis, S.; Markert, C.; Masui, H.; Matis, H. S.; McDonald, D.; Meehan, K.; Minaev, N. G.; Mioduszewski, S.; Mohanty, B.; Mondal, M. M.; Morozov, D.; Mustafa, M. K.; Nandi, B. K.; Nasim, Md.; Nayak, T. K.; Nigmatkulov, G.; Nogach, L. V.; Noh, S. Y.; Novak, J.; Nurushev, S. B.; Odyniec, G.; Ogawa, A.; Oh, K.; Okorokov, V.; Olvitt, D.; Page, B. S.; Pak, R.; Pan, Y. X.; Pandit, Y.; Panebratsev, Y.; Pawlik, B.; Pei, H.; Perkins, C.; Peterson, A.; Pile, P.; Planinic, M.; Pluta, J.; Poljak, N.; Poniatowska, K.; Porter, J.; Posik, M.; Poskanzer, A. M.; Pruthi, N. K.; Putschke, J.; Qiu, H.; Quintero, A.; Ramachandran, S.; Raniwala, R.; Raniwala, S.; Ray, R. L.; Ritter, H. G.; Roberts, J. B.; Rogachevskiy, O. V.; Romero, J. L.; Roy, A.; Ruan, L.; Rusnak, J.; Rusnakova, O.; Sahoo, N. R.; Sahu, P. K.; Sakrejda, I.; Salur, S.; Sandweiss, J.; Sarkar, A.; Schambach, J.; Scharenberg, R. P.; Schmah, A. M.; Schmidke, W. B.; Schmitz, N.; Seger, J.; Seyboth, P.; Shah, N.; Shahaliev, E.; Shanmuganathan, P. V.; Shao, M.; Sharma, M. K.; Sharma, B.; Shen, W. Q.; Shi, S. S.; Shou, Q. Y.; Sichtermann, E. P.; Sikora, R.; Simko, M.; Skoby, M. J.; Smirnov, D.; Smirnov, N.; Song, L.; Sorensen, P.; Spinka, H. M.; Srivastava, B.; Stanislaus, T. D. S.; Stepanov, M.; Stock, R.; Strikhanov, M.; Stringfellow, B.; Sumbera, M.; Summa, B.; Sun, X.; Sun, Z.; Sun, X. M.; Sun, Y.; Surrow, B.; Svirida, N.; Szelezniak, M. A.; Tang, A. H.; Tang, Z.; Tarnowsky, T.; Tawfik, A. N.; Thomas, J. H.; Timmins, A. R.; Tlusty, D.; Tokarev, M.; Trentalange, S.; Tribble, R. E.; Tribedy, P.; Tripathy, S. K.; Trzeciak, B. A.; Tsai, O. D.; Ullrich, T.; Underwood, D. G.; Upsal, I.; Van Buren, G.; van Nieuwenhuizen, G.; Vandenbroucke, M.; Varma, R.; Vasiliev, A. N.; Vertesi, R.; Videbæk, F.; Viyogi, Y. P.; Vokal, S.; Voloshin, S. A.; Vossen, A.; Wang, G.; Wang, Y.; Wang, F.; Wang, Y.; Wang, H.; Wang, J. S.; Webb, J. C.; Webb, G.; Wen, L.; Westfall, G. D.; Wieman, H.; Wissink, S. W.; Witt, R.; Wu, Y. F.; Xiao, Z. G.; Xie, W.; Xin, K.; Xu, Q. H.; Xu, Z.; Xu, H.; Xu, N.; Xu, Y. F.; Yang, Q.; Yang, Y.; Yang, S.; Yang, Y.; Yang, C.; Ye, Z.; Yepes, P.; Yi, L.; Yip, K.; Yoo, I. -K.; Yu, N.; Zbroszczyk, H.; Zha, W.; Zhang, X. P.; Zhang, J.; Zhang, Y.; Zhang, J.; Zhang, J. B.; Zhang, S.; Zhang, Z.; Zhao, J.; Zhong, C.; Zhou, L.; Zhu, X.; Zoulkarneeva, Y.; Zyzak, M.

    2015-08-24

    We report on measurements of dielectron (e⁺e⁻) production in Au+Au collisions at a center-of-mass energy of 200 GeV per nucleon-nucleon pair using the STAR detector at RHIC. Systematic measurements of the dielectron yield as a function of transverse momentum (pT) and collision centrality show an enhancement compared to a cocktail simulation of hadronic sources in the low invariant-mass region (Mee < 1GeV/c2). This enhancement cannot be reproduced by the ρ-meson vacuum spectral function. In minimum-bias collisions, in the invariant-mass range of 0.30 – 0.76GeV/c², integrated over the full pT acceptance, the enhancement factor is 1.76±0.06(stat.)±0.26(sys.)±0.29(cocktail). The enhancement factor exhibits weak centrality and pT dependence in STAR's accessible kinematic regions, while the excess yield in this invariant-mass region as a function of the number of participating nucleons follows a power-law shape with a power of 1.44±0.10. Models that assume an in-medium broadening of the ρ-meson spectral function consistently describe the observed excess in these measurements. In addition, we report on measurements of ω- and Φ-meson production through their e⁺e⁻ decay channel. These measurements show good agreement with Tsallis blast-wave model predictions, as well as, in the case of the Φ meson, results through its K⁺K⁻ decay channel. In the intermediate invariant-mass region (1.1 < Mee < 3GeV/c²), we investigate the spectral shapes from different collision centralities. Physics implications for possible in-medium modification of charmed hadron production and other physics sources are discussed.

  3. Au intensity enhancement for RHIC

    SciTech Connect (OSTI)

    S. Y. Zhang; Huang, H.

    2015-12-09

    In this article, possible improvement related to the AGS 6-3-1 bunch merge test is presented. After that, relevant issues for beams with larger longitudinal emittance at RHIC are discussed.

  4. p-Au ramp test

    SciTech Connect (OSTI)

    Montag, C.; Blaskiewicz, M.; Schoefer, V.; Blackler, I.; Shrey, T.

    2014-06-10

    During FY2015 RHIC will be providing proton-gold collisions for the first time. The large difference in Z/A of these species results in challenging conditions at injection. The two injection scenarios under investigation are injection at equal B? which results in different revolution frequencies of the two beams, and injection at equal revolution frequencies, which requires different rigidities of B? of protons and gold.

  5. Bounding the Higgs width at the LHC using full analytic results for $$gg → e^- e^+ \\mu^- \\mu^+$$

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Campbell, John M.; Ellis, R. Keith; Williams, Ciaran

    2014-04-09

    We revisit the hadronic production of the four-lepton final state, e– e+ μ– μ+, through the fusion of initial state gluons. This process is mediated by loops of quarks and we provide first full analytic results for helicity amplitudes that account for both the effects of the quark mass in the loop and off-shell vector bosons. The analytic results have been implemented in the Monte Carlo program MCFM and are both fast, and numerically stable in the region of low Z transverse momentum. We use our results to study the interference between Higgs-mediated and continuum production of four-lepton final states,more » which is necessary in order to obtain accurate theoretical predictions outside the Higgs resonance region. We have confirmed and extended a recent analysis of Caola and Melnikov that proposes to use a measurement of the off-shell region to constrain the total width of the Higgs boson. Using a simple cut-and-count method, existing LHC data should bound the width at the level of 25-45 times the Standard Model expectation. We investigate the power of using a matrix element method to construct a kinematic discriminant to sharpen the constraint. Furthermore, in our analysis the bound on the Higgs width is improved by a factor of about 1.6 using a simple cut on the MEM discriminant, compared to an invariant mass cut μ4l > 300 GeV.« less

  6. Bounding the Higgs width at the LHC using full analytic results for $gg → e^- e^+ \\mu^- \\mu^+$

    SciTech Connect (OSTI)

    Campbell, John M.; Ellis, R. Keith; Williams, Ciaran

    2014-04-09

    We revisit the hadronic production of the four-lepton final state, e e+ μ μ+, through the fusion of initial state gluons. This process is mediated by loops of quarks and we provide first full analytic results for helicity amplitudes that account for both the effects of the quark mass in the loop and off-shell vector bosons. The analytic results have been implemented in the Monte Carlo program MCFM and are both fast, and numerically stable in the region of low Z transverse momentum. We use our results to study the interference between Higgs-mediated and continuum production of four-lepton final states, which is necessary in order to obtain accurate theoretical predictions outside the Higgs resonance region. We have confirmed and extended a recent analysis of Caola and Melnikov that proposes to use a measurement of the off-shell region to constrain the total width of the Higgs boson. Using a simple cut-and-count method, existing LHC data should bound the width at the level of 25-45 times the Standard Model expectation. We investigate the power of using a matrix element method to construct a kinematic discriminant to sharpen the constraint. Furthermore, in our analysis the bound on the Higgs width is improved by a factor of about 1.6 using a simple cut on the MEM discriminant, compared to an invariant mass cut μ4l > 300 GeV.

  7. The evolution of 1 AU equatorial solar wind and its association with the morphology of the heliospheric current sheet from solar cycles 23 to 24

    SciTech Connect (OSTI)

    Zhao, L.; Landi, E.; Zurbuchen, T. H.; Fisk, L. A.; Lepri, S. T.

    2014-09-20

    The solar wind can be categorized into three types based on its 'freeze-in' temperature (T {sub freeze-in}) in the coronal source: low T {sub freeze-in} wind mostly from coronal holes, high T {sub freeze-in} wind mostly from regions outside of coronal holes, including streamers (helmet streamer and pseudostreamer), active regions, etc., and transient interplanetary coronal mass ejections (ICMEs) usually possessing the hottest T {sub freeze-in}. The global distribution of these three types of wind has been investigated by examining the most effective T {sub freeze-in} indicator, the O{sup 7+}/O{sup 6+} ratio, as measured by the Solar Wind Ion Composition Spectrometer on board the Advanced Composition Explorer (ACE) during 1998-2008 by Zhao et al. In this study, we extend the previous investigation to 2011 June, covering the unusual solar minimum between solar cycles 23 and 24 (2007-2010) and the beginning of solar cycle 24. We find that during the entire solar cycle, from the ascending phase of cycle 23 in 1998 to the ascending phase of cycle 24 in 2011, the average fractions of the low O{sup 7+}/O{sup 6+} ratio (LOR) wind, the high O{sup 7+}/O{sup 6+} ratio (HOR) wind, and ICMEs at 1 AU are 50.3%, 39.4%, and 10.3%, respectively; the contributions of the three types of wind evolve with time in very different ways. In addition, we compare the evolution of the HOR wind with two heliospheric current sheet (HCS) parameters, which indicate the latitudinal standard deviation (SD) and the slope (SL) of the HCS on the synoptic Carrington maps at 2.5 solar radii surface. We find that the fraction of HOR wind correlates with SD and SL very well (slightly better with SL than with SD), especially after 2005. This result verifies the link between the production of HOR wind and the morphology of the HCS, implying that at least one of the major sources of the HOR wind must be associated with the HCS.

  8. Microsoft Word - DOE-ID-11-015 Nevada EC.doc

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    high-temperature and high-pressure dynamic water loop equipment for mechanical and corrosion testing. UNR will evaluate mechanical performance of various alloys at extreme...

  9. Geothermal Site Assessment Using the National Geothermal Data...

    Open Energy Info (EERE)

    www.unr.edugeothermalpdffilesPenfieldGRC2010GeothermalSiteAssessme Cost: Free Language: English References: Paper1 "This paper examines the features and functionality of...

  10. Applications Now Being Accepted for National Geothermal Academy...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    The course is a collaborative effort among faculty from the University of Nevada, Reno (UNR), Stanford University, Cornell University, Oregon Institute of Technology (OIT), ...

  11. Nevada Bureau of Mines and Geology | Open Energy Information

    Open Energy Info (EERE)

    Address: University of Nevada178 Place: Nevada Zip: 89557 Website: www.nbmg.unr.eduOil&Gasindex Coordinates: 39.5440601, -119.8136573 Show Map Loading map......

  12. Measurement of K0S and K*0 in p+p, d+Au, and Cu+Cu collisions at sqrt SNN = 200 GeV

    SciTech Connect (OSTI)

    Adare, A.; Aidala, C.

    2014-11-01

    The PHENIX experiment at the Relativistic Heavy Ion Collider has performed a systematic study of K0S and K*0 meson production at midrapidity in p+p, d+Au, and Cu+Cu collisions at sqrt SNN = 200 GeV. The K0S and K*0 mesons are reconstructed via their K0S and ?0(???)?0 (???) and K*0 ? K #25;? decay modes, respectively. The measured transverse-momentum spectra are used to determine the nuclear modification factor of K0S and K*0 mesons in d+Au and Cu+Cu collisions at different centralities. In the d+Au collisions, the nuclear modification factor of K0S and K*0 mesons is almost constant as a function of transverse momentum and is consistent with unity showing that cold-nuclear-matter effects do not play a significant role in the measured kinematic range. In Cu+Cu collisions, within the uncertainties no nuclear modification is registered in peripheral collisions. In central collisions, both mesons show suppression relative to the expectations from the p+p yield scaled by the number of binary nucleon-nucleon collisions in the Cu+Cu system. In the pT range 25 GeV/c, the strange mesons ( K0S, K*0) similarly to the #30;? meson with hidden strangeness, show an intermediate suppression between the more suppressed light quark mesons (?0) and the nonsuppressed baryons (p, p-bar). At higher transverse momentum, pT > 5 GeV/c, production of all particles is similarly suppressed by a factor of ?2. (auth)

  13. Temperature-induced sign change of the magnetic interlayer coupling in Ni/Ni{sub 25}Mn{sub 75}/Ni trilayers on Cu{sub 3}Au(001)

    SciTech Connect (OSTI)

    Shokr, Y. A.; Zhang, B.; Sandig, O.; Kuch, W.; Erkovan, M.; Wu, C.-B.

    2015-05-07

    We investigated the magnetic interlayer coupling between two ferromagnetic (FM) Ni layers through an antiferromagnetic (AFM) Ni{sub 25}Mn{sub 75} layer and the influence of this coupling on the exchange bias phenomenon. The interlayer coupling energy of an epitaxial trilayer of 14 atomic monolayers (ML) Ni/45 ML Ni{sub 25}Mn{sub 75}/16 ML Ni on Cu{sub 3}Au(001) was extracted from minor-loop magnetization measurements using in-situ magneto-optical Kerr effect. The interlayer coupling changes from ferromagnetic to antiferromagnetic when the temperature is increased above 300?K. This sign change is interpreted as the result of the competition between an antiparallel Ruderman-Kittel-Kasuya-Yosida (RKKY)-type interlayer coupling, which dominates at high temperature, and a stronger direct exchange coupling across the AFM layer, which is present only below the Nel temperature of the AFM layer.

  14. Breakup of the projectile in [sup 16]O-induced reactions on [sup 27]Al, [sup 58]Ni, and [sup 197]Au targets around 100 MeV/nucleon

    SciTech Connect (OSTI)

    Badala, A.; Barbera, R.; Palmeri, A.; Pappalardo, G.S. (Istituto Nazionale di Fisica Nucleare, Sezione di Catania, Corso Italia 57, 95129 Catania (Italy)); Riggi, F. (Istituto Nazionale di Fisica Nucleare, Sezione di Catania, Corso Italia 57, 95129 Catania (Italy) Dipartimento di Fisica dell'Universita di Catania, Corso Italia 57, 95129 Catania (Italy))

    1993-08-01

    The spatial correlation among the four He ions coming from the disassembly of the [sup 16]O projectile on [sup 27]Al, [sup 58]Ni, and [sup 197]Au targets has been studied at 94 MeV/nucleon. Charged particles have been detected by a multielement array of plastic scintillators covering the angular domain between 3[degree] and 150[degree]. Standard relativistic kinematics has been used to reconstruct the excitation energy of the primary projectilelike nucleus ([ital E][sub PLN][sup *]). Mean values of this quantity are found independent of the target mass and the comparison with existing similar data taken at lower bombarding energies shows a saturation of [ital E][sub PLN][sup *] around 3 MeV/nucleon. An event-by-event analysis has been performed in order to study the distributions of some global variables such as coplanarity, sphericity, and relative angle, helpful in the understanding of the topological characteristics of the process and in the evaluation of its time scale. Experimental data have also been compared with the results of Monte Carlo simulations based on different reaction mechanisms and it is possible to conclude that sequential emission of the fragments is preferred.

  15. Cross section for bb¯ production via dielectrons in d + Au collisions at sNN=200 GeV

    SciTech Connect (OSTI)

    Adare, A.; Aidala, C.; Ajitanand, N. N.; Akiba, Y.; Al-Bataineh, H.; Alexander, J.; Angerami, A.; Aoki, K.; Apadula, N.; Aramaki, Y.; Atomssa, E. T.; Averbeck, R.; Awes, T. C.; Azmoun, B.; Babintsev, V.; Bai, M.; Baksay, G.; Baksay, L.; Barish, K. N.; Bassalleck, B.; Basye, A. T.; Bathe, S.; Baublis, V.; Baumann, C.; Bazilevsky, A.; Belikov, S.; Belmont, R.; Bennett, R.; Bhom, J. H.; Blau, D. S.; Bok, J. S.; Boyle, K.; Brooks, M. L.; Buesching, H.; Bumazhnov, V.; Bunce, G.; Butsyk, S.; Campbell, S.; Caringi, A.; Chen, C. -H.; Chi, C. Y.; Chiu, M.; Choi, I. J.; Choi, J. B.; Choudhury, R. K.; Christiansen, P.; Chujo, T.; Chung, P.; Chvala, O.; Cianciolo, V.; Citron, Z.; Cole, B. A.; Conesa del Valle, Z.; Connors, M.; Csanád, M.; Csörgő, T.; Dahms, T.; Dairaku, S.; Danchev, I.; Das, K.; Datta, A.; David, G.; Dayananda, M. K.; Denisov, A.; Deshpande, A.; Desmond, E. J.; Dharmawardane, K. V.; Dietzsch, O.; Dion, A.; Donadelli, M.; Drapier, O.; Drees, A.; Drees, K. A.; Durham, J. M.; Durum, A.; Dutta, D.; D'Orazio, L.; Edwards, S.; Efremenko, Y. V.; Ellinghaus, F.; Engelmore, T.; Enokizono, A.; En'yo, H.; Esumi, S.; Fadem, B.; Fields, D. E.; Finger, M.; Finger, M.; Fleuret, F.; Fokin, S. L.; Fraenkel, Z.; Frantz, J. E.; Franz, A.; Frawley, A. D.; Fujiwara, K.; Fukao, Y.; Fusayasu, T.; Garishvili, I.; Glenn, A.; Gong, H.; Gonin, M.; Goto, Y.; Granier de Cassagnac, R.; Grau, N.; Greene, S. V.; Grim, G.; Grosse Perdekamp, M.; Gunji, T.; Gustafsson, H. -Å.; Haggerty, J. S.; Hahn, K. I.; Hamagaki, H.; Hamblen, J.; Han, R.; Hanks, J.; Haslum, E.; Hayano, R.; He, X.; Heffner, M.; Hemmick, T. K.; Hester, T.; Hill, J. C.; Hohlmann, M.; Holzmann, W.; Homma, K.; Hong, B.; Horaguchi, T.; Hornback, D.; Huang, S.; Ichihara, T.; Ichimiya, R.; Ikeda, Y.; Imai, K.; Inaba, M.; Isenhower, D.; Ishihara, M.; Issah, M.; Ivanischev, D.; Iwanaga, Y.; Jacak, B. V.; Jia, J.; Jiang, X.; Jin, J.; Johnson, B. M.; Jones, T.; Joo, K. S.; Jouan, D.; Jumper, D. S.; Kajihara, F.; Kamin, J.; Kang, J. H.; Kapustinsky, J.; Karatsu, K.; Kasai, M.; Kawall, D.; Kawashima, M.; Kazantsev, A. V.; Kempel, T.; Khanzadeev, A.; Kijima, K. M.; Kikuchi, J.; Kim, A.; Kim, B. I.; Kim, D. J.; Kim, E. -J.; Kim, Y. -J.; Kinney, E.; Kiss, Á.; Kistenev, E.; Kleinjan, D.; Kochenda, L.; Komkov, B.; Konno, M.; Koster, J.; Král, A.; Kravitz, A.; Kunde, G. J.; Kurita, K.; Kurosawa, M.; Kwon, Y.; Kyle, G. S.; Lacey, R.; Lai, Y. S.; Lajoie, J. G.; Lebedev, A.; Lee, D. M.; Lee, J.; Lee, K. B.; Lee, K. S.; Leitch, M. J.; Leite, M. A. L.; Li, X.; Lichtenwalner, P.; Liebing, P.; Linden Levy, L. A.; Liška, T.; Liu, H.; Liu, M. X.; Love, B.; Lynch, D.; Maguire, C. F.; Makdisi, Y. I.; Malik, M. D.; Manko, V. I.; Mannel, E.; Mao, Y.; Masui, H.; Matathias, F.; McCumber, M.; McGaughey, P. L.; McGlinchey, D.; Means, N.; Meredith, B.; Miake, Y.; Mibe, T.; Mignerey, A. C.; Miki, K.; Milov, A.; Mitchell, J. T.; Mohanty, A. K.; Moon, H. J.; Morino, Y.; Morreale, A.; Morrison, D. P.; Moukhanova, T. V.; Murakami, T.; Murata, J.; Nagamiya, S.; Nagle, J. L.; Naglis, M.; Nagy, M. I.; Nakagawa, I.; Nakamiya, Y.; Nakamura, K. R.; Nakamura, T.; Nakano, K.; Nam, S.; Newby, J.; Nguyen, M.; Nihashi, M.; Nouicer, R.; Nyanin, A. S.; Oakley, C.; O'Brien, E.; Oda, S. X.; Ogilvie, C. A.; Oka, M.; Okada, K.; Onuki, Y.; Oskarsson, A.; Ouchida, M.; Ozawa, K.; Pak, R.; Pantuev, V.; Papavassiliou, V.; Park, I. H.; Park, S. K.; Park, W. J.; Pate, S. F.; Pei, H.; Peng, J. -C.; Pereira, H.; Peressounko, D. Yu.; Petti, R.; Pinkenburg, C.; Pisani, R. P.; Proissl, M.; Purschke, M. L.; Qu, H.; Rak, J.; Ravinovich, I.; Read, K. F.; Rembeczki, S.; Reygers, K.; Riabov, V.; Riabov, Y.; Richardson, E.; Roach, D.; Roche, G.; Rolnick, S. D.; Rosati, M.; Rosen, C. A.; Rosendahl, S. S. E.; Ružička, P.; Sahlmueller, B.; Saito, N.; Sakaguchi, T.; Sakashita, K.; Samsonov, V.; Sano, S.; Sato, T.; Sawada, S.; Sedgwick, K.; Seele, J.; Seidl, R.; Seto, R.; Sharma, D.; Shein, I.; Shibata, T. -A.; Shigaki, K.; Shimomura, M.; Shoji, K.; Shukla, P.; Sickles, A.; Silva, C. L.; Silvermyr, D.; Silvestre, C.; Sim, K. S.; Singh, B. K.; Singh, C. P.; Singh, V.; Slunečka, M.; Soltz, R. A.; Sondheim, W. E.; Sorensen, S. P.; Sourikova, I. V.; Stankus, P. W.; Stenlund, E.; Stoll, S. P.; Sugitate, T.; Sukhanov, A.; Sziklai, J.; Takagui, E. M.; Taketani, A.; Tanabe, R.; Tanaka, Y.; Taneja, S.; Tanida, K.; Tannenbaum, M. J.; Tarafdar, S.; Taranenko, A.; Themann, H.; Thomas, D.; Thomas, T. L.; Togawa, M.; Toia, A.; Tomášek, L.; Torii, H.; Towell, R. S.; Tserruya, I.; Tsuchimoto, Y.; Vale, C.; Valle, H.; van Hecke, H. W.; Vazquez-Zambrano, E.; Veicht, A.; Velkovska, J.; Vértesi, R.; Virius, M.; Vrba, V.; Vznuzdaev, E.; Wang, X. R.; Watanabe, D.; Watanabe, K.; Watanabe, Y.; Wei, F.; Wei, R.; Wessels, J.; White, S. N.; Winter, D.; Woody, C. L.; Wright, R. M.; Wysocki, M.; Yamaguchi, Y. L.; Yamaura, K.; Yang, R.; Yanovich, A.; Ying, J.; Yokkaichi, S.; You, Z.; Young, G. R.; Younus, I.; Yushmanov, I. E.; Zajc, W. A.; Zhou, S.

    2015-01-26

    We report a measurement of e⁺e⁻ pairs from semileptonic heavy-flavor decays in d+Au collisions at √sNN = 200 GeV. Thus, exploring the mass and transverse-momentum dependence of the yield, the bottom decay contribution can be isolated from charm, and quantified by comparison to PYTHIA and MC@NLO simulations. The resulting bb-production cross section is σdAubb=1.37±0.28(stat)±0.46(syst) mb, which is equivalent to a nucleon-nucleon cross section of σNNbb =3.4 ± 0.8(stat)±1.1(syst) µb.

  16. THE MINERALOGY AND STRUCTURE OF THE INNER DEBRIS DISK OF {beta} PICTORIS

    SciTech Connect (OSTI)

    Li Dan; Telesco, Charles M.; Wright, Christopher M.

    2012-11-10

    We observed the edge-on, planet-bearing disk of {beta} Pictoris using T-ReCS at Gemini to clarify and extend previous observations and conclusions about this unique system. Our spectroscopy and spectral modeling of the 10 {mu}m silicate feature constrain the spatial distributions of three representative dust components (0.1 {mu}m/2.0 {mu}m glassy olivine and crystalline forsterite) across the inner 20 AU of the disk. We confirm that the 2.0 {mu}m glassy olivine is strongly peaked in the disk center and that the 0.1 {mu}m glassy olivine does not show this concentration, but rather is double peaked, with the peaks on either side of the star. However, we do not see the strong difference in brightness between those two peaks reported in a previous study. Although the spatial distribution of the 0.1 {mu}m dust is consistent with the scenario of a dust-replenishing planetesimal belt embedded in the disk, we note an alternative interpretation that can explain the spatial distributions of the 0.1 {mu}m and 2.0 {mu}m grains simultaneously and does not require the planetesimal belt. In addition to the spectroscopy, we also obtained a new 11.7 {mu}m image of the {beta} Pic disk. By comparing this image with that acquired in 2003, we confirm the existence and overall shape of the dusty clump at 52 AU in the SW disk. We speculate that the clump's projected spatial displacement of {approx}2.0 AU, a 3.6{sigma} result, between two epochs separated by seven years is due to the Keplerian motion of the clump at an orbital radius of 54.3{sup +2.0} {sub -1.2} AU.

  17. Observation of the rare $B^0_s\\to\\mu^+\\mu^-$ decay from the combined analysis of CMS and LHCb data

    SciTech Connect (OSTI)

    Khachatryan, Vardan

    2015-05-13

    The standard model of particle physics describes the fundamental particles and their interactions via the strong, electromagnetic and weak forces. It provides precise predictions for measurable quantities that can be tested experimentally. We foudn that the probabilities, or branching fractions, of the strange B meson (B 02 ) and the B0 meson decaying into two oppositely charged muons (μ+ and μ-) are especially interesting because of their sensitivity to theories that extend the standard model. The standard model predicts that the B 02 → μ+ and μ- and (B 0 → μ+ and μ- decays are very rare, with about four of the former occurring for every billion mesons produced, and one of the latter occurring for every ten billion B0 mesons1. A difference in the observed branching fractions with respect to the predictions of the standard model would provide a direction in which the standard model should be extended. Before the Large Hadron Collider (LHC) at CERN2 started operating, no evidence for either decay mode had been found. Upper limits on the branching fractions were an order of magnitude above the standard model predictions. The CMS (Compact Muon Solenoid) and LHCb (Large Hadron Collider beauty) collaborations have performed a joint analysis of the data from proton–proton collisions that they collected in 2011 at a centre-of-mass energy of seven teraelectronvolts and in 2012 at eight teraelectronvolts. Here we report the first observation of the μ+ and μ-decay, with a statistical significance exceeding six standard deviations, and the best measurement so far of its branching fraction. We then obtained evidence for the B 0 → μ+ and μ- decay with a statistical significance of three standard deviations. Both measurements are statistically compatible with standard model predictions and allow stringent constraints to be placed on theories beyond the standard model. The LHC experiments will resume taking data in 2015, recording proton–proton collisions at a centre-of-mass energy of 13 teraelectronvolts, which will approximately double the production rates of B 02 and B0 mesons and lead to further improvements in the precision of these crucial tests of the standard model.

  18. Observation of the rare $$B^0_s\\to\\mu^+\\mu^-$$ decay from the combined analysis of CMS and LHCb data

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Khachatryan, Vardan

    2015-05-13

    The standard model of particle physics describes the fundamental particles and their interactions via the strong, electromagnetic and weak forces. It provides precise predictions for measurable quantities that can be tested experimentally. We foudn that the probabilities, or branching fractions, of the strange B meson (B 02 ) and the B0 meson decaying into two oppositely charged muons (μ+ and μ-) are especially interesting because of their sensitivity to theories that extend the standard model. The standard model predicts that the B 02 → μ+ and μ- and (B 0 → μ+ and μ- decays are very rare, with aboutmore » four of the former occurring for every billion mesons produced, and one of the latter occurring for every ten billion B0 mesons1. A difference in the observed branching fractions with respect to the predictions of the standard model would provide a direction in which the standard model should be extended. Before the Large Hadron Collider (LHC) at CERN2 started operating, no evidence for either decay mode had been found. Upper limits on the branching fractions were an order of magnitude above the standard model predictions. The CMS (Compact Muon Solenoid) and LHCb (Large Hadron Collider beauty) collaborations have performed a joint analysis of the data from proton–proton collisions that they collected in 2011 at a centre-of-mass energy of seven teraelectronvolts and in 2012 at eight teraelectronvolts. Here we report the first observation of the μ+ and μ-decay, with a statistical significance exceeding six standard deviations, and the best measurement so far of its branching fraction. We then obtained evidence for the B 0 → μ+ and μ- decay with a statistical significance of three standard deviations. Both measurements are statistically compatible with standard model predictions and allow stringent constraints to be placed on theories beyond the standard model. The LHC experiments will resume taking data in 2015, recording proton–proton collisions at a centre-of-mass energy of 13 teraelectronvolts, which will approximately double the production rates of B 02 and B0 mesons and lead to further improvements in the precision of these crucial tests of the standard model.« less

  19. An analysis of the pull strength behaviors of fine-pitch, flip chip solder interconnections using a Au-Pt-Pd thick film conductor on Low-Temperature, Co-fired Ceramic (LTCC) substrates.

    SciTech Connect (OSTI)

    Uribe, Fernando R.; Kilgo, Alice C.; Grazier, John Mark; Vianco, Paul Thomas; Zender, Gary L.; Hlava, Paul Frank; Rejent, Jerome Andrew

    2008-09-01

    The assembly of the BDYE detector requires the attachment of sixteen silicon (Si) processor dice (eight on the top side; eight on the bottom side) onto a low-temperature, co-fired ceramic (LTCC) substrate using 63Sn-37Pb (wt.%, Sn-Pb) in a double-reflow soldering process (nitrogen). There are 132 solder joints per die. The bond pads were gold-platinum-palladium (71Au-26Pt-3Pd, wt.%) thick film layers fired onto the LTCC in a post-process sequence. The pull strength and failure modes provided the quality metrics for the Sn-Pb solder joints. Pull strengths were measured in both the as-fabricated condition and after exposure to thermal cycling (-55/125 C; 15 min hold times; 20 cycles). Extremely low pull strengths--referred to as the low pull strength phenomenon--were observed intermittently throughout the product build, resulting in added program costs, schedule delays, and a long-term reliability concern for the detector. There was no statistically significant correlation between the low pull strength phenomenon and (1) the LTCC 'sub-floor' lot; (2) grit blasting the LTCC surfaces prior to the post-process steps; (3) the post-process parameters; (4) the conductor pad height (thickness); (5) the dice soldering assembly sequence; or (5) the dice pull test sequence. Formation of an intermetallic compound (IMC)/LTCC interface caused by thick film consumption during either the soldering process or by solid-state IMC formation was not directly responsible for the low-strength phenomenon. Metallographic cross sections of solder joints from dice that exhibited the low pull strength behavior, revealed the presence of a reaction layer resulting from an interaction between Sn from the molten Sn-Pb and the glassy phase at the TKN/LTCC interface. The thick film porosity did not contribute, explicitly, to the occurrence of reaction layer. Rather, the process of printing the very thin conductor pads was too sensitive to minor thixotropic changes to ink, which resulted in inconsistent proportions of metal and glassy phase particles present during the subsequent firing process. The consequences were subtle, intermittent changes to the thick film microstructure that gave rise to the reaction layer and, thus, the low pull strength phenomenon. A mitigation strategy would be the use of physical vapor deposition (PVD) techniques to create thin film bond pads; this is multi-chip module, deposited (MCM-D) technology.

  20. New compact hohlraum configuration research at the 1.7 MA Z-pinch generator

    SciTech Connect (OSTI)

    Kantsyrev, V. L. Shrestha, I. K.; Esaulov, A. A.; Safronova, A. S.; Shlyaptseva, V. V.; Osborne, G. C.; Astanovitsky, A. L.; Weller, M. E.; Stafford, A.; Schultz, K. A.; Cooper, M. C.; Chuvatin, A. S.; Rudakov, L. I.; Velikovich, A. L.; Cuneo, M. E.; Jones, B.; Vesey, R. A.

    2014-12-15

    A new compact Z-pinch x-ray hohlraum design with parallel-driven x-ray sources was experimentally demonstrated in a full configuration with a central target and tailored shine shields (to provide a symmetric temperature distribution on the target) at the 1.7 MA Zebra generator. This presentation reports on the joint success of two independent lines of research. One of these was the development of new sources – planar wire arrays (PWAs). PWAs turned out to be a prolific radiator. Another success was the drastic improvement in energy efficiency of pulsed-power systems, such as the Load Current Multiplier (LCM). The Zebra/LCM generator almost doubled the plasma load current to 1.7 MA. The two above-mentioned innovative approaches were used in combination to produce a new compact hohlraum design for ICF, as jointly proposed by SNL and UNR. Good agreement between simulated and measured radiation temperature of the central target is shown. Experimental comparison of PWAs with planar foil liners (PFL) - another viable alternative to wire array loads at multi-MA generators show promising data. Results of research at the University of Nevada Reno allowed for the study of hohlraum coupling physics at University-scale generators. The advantages of new hohlraum design applications for multi-MA facilities with W or Au double PWAs or PFL x-ray sources are discussed.

  1. Widespread effects of middle Mississippian deformation in the...

    National Nuclear Security Administration (NNSA)

    ... Footnotes trexler@mines.unr.edu GSA Data Repository item 2003139, detailed regional discussion of stratigraphy in Nevada, is available on the Web at http:www.geosociety.org...

  2. CoverSheet

    Office of Scientific and Technical Information (OSTI)

    to Mssrs. Bob White and Ryan Em- mitt (NSTec) for their tireless support on the seismic array and to the University of Nevada, Reno (UNR) for their support with the seismic...

  3. SSAP Annual_13may2013.indb

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    1.7 MA Zebra at UNR. a) Photograph of Triple Wire Array load. b) Wire Ablation Dynamic Model predictions at 60 nsec (view from the top). Dotted arrowed lines show the direction of...

  4. Identification of Au-S complexes on Au(100) (Journal Article...

    Office of Scientific and Technical Information (OSTI)

    PCCP (Print) Additional Journal Information: Journal Name: Physical Chemistry Chemical Physics. PCCP ... Language: English Subject: 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL ...

  5. Target and orbit feedback simulations of a muSR beam line at BNL

    SciTech Connect (OSTI)

    MacKay, W.; Blaskiewicz, M.; Fischer, W.; Pile, P.

    2015-07-28

    Well-polarized positive surface muons are a tool to measure the magnetic properties of materials since the precession rate of the spin can be determined from the observation of the positron directions when the muons decay. For a dc beam an ideal µSR flux for surface µ+ should be about 40 kHz/mm2. In this report we show how this flux could be achieved in a beam line using the AGS complex at BNL for a source of protons. We also determined that an orbit feedback system with a pair of thin silicon position monitors and kickers would miss the desired flux by at least an order of magnitude, even with perfect time resolution and no multiple scattering.

  6. Feedback-based, muLti-dimensional Interface as a General Human-Computer Tech.

    Energy Science and Technology Software Center (OSTI)

    2002-05-13

    FLIGHT is a 3D human-computer interface and application development software that can be used by both end users and programmers. It is based on advanced feedback and a multi-dimensional nature that more closely resembles real life interactions. The software uses a craft metaphor and allows multimodal feedback for advanced tools and navigation techniques. Overall, FLIGHT is a software that is based on the principle that as the human-computer interface is strengthened through the use ofmore » more intuitive inputs and more effective feedback, the computer itself will be for more valuable. FLIGHT has been used to visualize scientific data sets in 3D graphics at Sandia National Laboratories.« less

  7. Tau neutrinos underground: Signals of {nu}{sub {mu}}{yields}...

    Office of Scientific and Technical Information (OSTI)

    above 10--100 TeV initiated by the extragalactic neutrinos. We show that the tau neutrinos from point sources also have the potential for discovery above a 1 TeV threshold. ...

  8. Effects of quadrupole vibration of the fragments on. mu. - final state probabilities

    SciTech Connect (OSTI)

    Zheng Guo-tong; Wang Yan-sen; Yuan Zu-shu; Qiu Zhi-hong

    1988-01-01

    The muon final-state probabilities after muon-induced fission of /sup 238/U are calculated by using the LCAO (Linear Combination of Atomic Orbital) method. The ordinary viscosity of the fissioning nucleus, the deformations and quadrupole vibrations of the two fragments are taken into account. The calculated results are compared with those obtained by neglecting the quadrupole vibration

  9. Mantid - Data Analysis and Visualization Package for Neutron Scattering and $\\mu SR$ Experiments

    SciTech Connect (OSTI)

    Arnold, Owen; Bilheux, Jean-Christophe; Borreguero Calvo, Jose M; Buts, Alex; Campbell, Stuart I; Doucet, Mathieu; Draper, Nicholas J; Ferraz Leal, Ricardo F; Gigg, Martyn; Lynch, Vickie E; Mikkelson, Dennis J; Mikkelson, Ruth L; Miller, Ross G; Perring, Toby G; Peterson, Peter F; Ren, Shelly; Reuter, Michael A; Savici, Andrei T; Taylor, Jonathan W; Taylor, Russell J; Zhou, Wenduo; Zikovsky, Janik L

    2014-11-01

    The Mantid framework is a software solution developed for the analysis and visualization of neutron scattering and muon spin measurements. The framework is jointly developed by a large team of software engineers and scientists at the ISIS Neutron and Muon Facility and the Oak Ridge National Laboratory. The objective of the development is to improve software quality, both in terms of performance and ease of use, for the the user community of large scale facilities. The functionality and novel design aspects of the framework are described.

  10. Mass spectrum analysis of K- pi+ from the semileptonic decay D+ --> K- pi+ mu+ nu

    SciTech Connect (OSTI)

    Massafferri Rodrigues, Andre

    2004-03-01

    The Higgs mechanism preserves the gauge symmetries of the Standard Model while giving masses to the W, Z bosons. Supersymmetry, which protects the Higgs boson mass scale from quantum corrections, predicts at least 5 Higgs bosons, none of which has been directly observed. This thesis presents a search for neutral Higgs bosons, produced in association with bottom quarks. The production rate is greatly enhanced at large values of the Supersymmetric parameter tan {beta}. High-energy p{bar p} collision data, collected from Run II of the Fermilab Tevatron using the D0 detector, are analyzed. In the absence of a signal, values of tan {beta} > 80-120 are excluded at 95% Confidence Level (C.L.), depending on the (CP-odd) neutral Higgs boson mass (studied from 100 to 150 GeV/c{sup 2}).

  11. Crystal structure of the[mu]-opioid receptor bound to a morphinan...

    Office of Scientific and Technical Information (OSTI)

    Resource Relation: Journal Name: Nature; Journal Volume: 485; Journal Issue: 7398 Research ... Language: ENGLISH Subject: 60 APPLIED LIFE SCIENCES; BIOLOGY; CENTRAL NERVOUS SYSTEM; ...

  12. Noise and zero point drift in 1.7 mu m cutoff detectors forSNAP...

    Office of Scientific and Technical Information (OSTI)

    Spatial andtemporal noise measurements are compared, and a simple method forquantifying the effect of hot pixels and RTS noise on spatial noise isdescribed. Authors: Smith, Roger ; ...

  13. -------------------------------------------------------------------------------- Metamaterial composition comprising frequency-selective-surface resonant element disposed on/in a dielectric flake, methods, and applications

    DOE Patents [OSTI]

    Shelton, David; Boreman, Glenn; D'Archangel, Jeffrey

    2015-11-10

    Infrared metamaterial arrays containing Au elements immersed in a medium of benzocyclobutene (BCB) were fabricated and selectively etched to produce small square flakes with edge dimensions of approximately 20 .mu.m. Two unit-cell designs were fabricated: one employed crossed-dipole elements while the other utilized square-loop elements.

  14. NEW SPATIALLY RESOLVED MID-INFRARED OBSERVATIONS OF THE TRANSITIONAL DISK TW Hya AND TENTATIVE EVIDENCE FOR A SELF-LUMINOUS COMPANION

    SciTech Connect (OSTI)

    Arnold, Timothy J.; Eisner, J. A.; Monnier, J. D.; Tuthill, Peter E-mail: jeisner@email.arizona.edu E-mail: p.tuthill@physics.usyd.edu.au

    2012-05-10

    We present spatially resolved observations of the canonical transition disk object TW Hya at 8.74 {mu}m, 11.66 {mu}m, and 18.30 {mu}m, obtained with the T-ReCS instrument on the Gemini telescope. These observations are a result of a novel observing mode at Gemini that enables speckle imaging. Using this technique, we image our target with short enough exposure times to achieve diffraction limited images. We use Fourier techniques to reduce our data, which allows high-precision calibration of the instrumental point-spread function. Our observations span two epochs and we present evidence for temporal variability at 11.66 {mu}m in the disk of TW Hya. We show that previous models of TW Hya's disk from the literature are incompatible with our observations and construct a model to explain the discrepancies. We detect marginal asymmetry in our data, most significantly at the shortest wavelengths. To explain our data, we require a model that includes an optically thin inner disk extending from 0.02 to 3.9 AU, an optically thick ring representing the outer disk wall at 3.9 AU and extending to 4.6 AU, and a hotter-than-disk-equilibrium source of emission located at {approx}3.5 AU.

  15. Probing the Unique Size-Dependent Properties of Small Au Clusters, Au Alloy Clusters, and CO Chemisorbed Au Clusters in the Gas Phase

    SciTech Connect (OSTI)

    Zhai, Hua-jin; Li, Xi; Wang, Lai S.

    2007-04-01

    When materials are reduced in size to the nanometer scale, their physical and chemical properties undergo major changes and become size-dependent, forming the foundation for nanoscience and nanotechnology. Gold nanoparticles and small gold clusters have been the focus of intensive research activities lately. The modern goldrush is largely motivated by the recent discoveries that (i) nanogold shows unexpected catalytic properties for a wide spectrum of chemical reactions [1], (ii) nanogold enables selective binding to biomolecules such as DNA and thus can serve as biosensors [2], (iii) gold has important potential applications in nanoelectronics [3,4], and (iv) gold clusters and gold-containing compounds possess unique chemical properties [5]. All these golden discoveries have made gold a surprising and rewarding subject of investigation in nanoscience and cluster science. Indeed, some of our oldest notions regarding gold, such as its inertness, are being changed dramatically by the recent findings in nanogold.

  16. A=19B (1995TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    95TI07) (Not illustrated) 19B has been observed in the bombardment of Be by 12 MeV/A 56Fe ions (1984MU27) and in the fragmentation of 44 MeV/A 40Ar (1988GU1A) and 55 MeV/A 48Ca (1991MU19). See also (1989DE52). The mass excess adopted by (1993AU05) is 59.360 ± 0.400 MeV. Shell model predictions for low-lying levels are discussed in (1992WA22). See also (1989PO1K, 1990LO11

  17. A=20N (1998TI06)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    98TI06) (Not illustrated) 20N is particle stable. Its atomic mass excess is 21.770 ± 0.050 MeV (1995AU04). It has been observed in heavy-ion transfer (1989OR03) and projectile fragmentation reactions (1987GI05, 1988DUZT, 1988MU08, 1990MU06, 1991OR01) and in target fragmentation reactions (1988WO09, 1991RE02, 1993WOZZ). See also the review (1988VI1D). Mass measurements were reported in (1987GI05, 1988WO09, 1989OR03, 1991OR01, 1993WOZZ). Nuclear matter rms radii have been derived from

  18. Routine production of copper-64 using 11.7MeV protons

    SciTech Connect (OSTI)

    Jeffery, C. M.; Smith, S. V.; Asad, A. H.; Chan, S.; Price, R. I.

    2012-12-19

    Reliable production of copper-64 ({sup 64}Cu) was achieved by irradiating enriched nickel-64 ({sup 64}Ni, >94.8%) in an IBA 18/9 cyclotron. Nickel-64 (19.1 {+-} 3.0 mg) was electroplated onto an Au disc (125{mu}m Multiplication-Sign 15mm). Targets were irradiated with 11.7 MeV protons for 2 hours at 40{mu}A. Copper isotopes ({sup 60,61,62,64}Cu) were separated from target nickel and cobalt isotopes ({sup 55,57,61}Co) using a single ion exchange column, eluted with varying concentration of low HCl alcohol solutions. The {sup 64}Ni target material was recovered and reused. The {sup 64}Cu production rate was 1.46{+-}0.3MBq/{mu}A.hr/mg{sup 64}Ni(n = 10) (with a maximum of 2.6GBq of {sup 64}Cu isolated after 2hr irradiation at 40uA. Radionuclidic purity of the {sup 64}Cu was 98.7 {+-} 1.6 % at end of separation. Cu content was < 6mg/L (n = 21). The specific activity of {sup 64}Cu was determined by ICP-MS and by titration with Diamsar to be 28.9{+-}13.0GBq/{mu}mol[0.70{+-}0.35Ci/{mu}mol]/({mu}A.hr/mg{sup 64}Ni)(n = 10) and 13.1{+-}12.0GBq/{mu}mol[0.35{+-}0.32Ci/{mu}mol]/({mu}A.hr/mg{sup 64}Ni)(n 9), respectively; which are in agreement, however, further work is required.

  19. Structural Phase Transition in AuZn Alloys

    SciTech Connect (OSTI)

    Winn,B.L.; Shapiro, S.M.; Lashley, J.C.; Opeil, C.; Ratcliff, W.

    2009-05-03

    AuxZn1-x alloys undergo a shape memory martensitic transformation whose temperature and nature (continuous or discontinuous) is strongly composition dependent. Neutron diffraction experiments were performed on single crystals of x=50 and 52 to explore the structural changes occurring at the transition temperature. A transverse modulation with wavevector q0=(1/3,1/3,0) develops below the transition temperature, with no observable change in lattice parameter. However, the Bragg peak width shows a broadening suggesting an unresolved rhombohedral distortion similar to what has been observed in NiTi-Fe alloys.

  20. Theoretical study of Ag- and Au-filled skutterudites.

    Broader source: Energy.gov [DOE]

    Uses ab initio atomistic DFT modeling as implemented in VASP to determine theoretical values of thermoelectric properties for Ag-filled skutterudites.

  1. Isle au Haut, Maine: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 44.0753601, -68.6333583 Show Map Loading map... "minzoom":false,"mappingservice":"googlemaps3","type"...

  2. AU Functional Area Points of Contact by Office Directors | Department...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    2015 More Documents & Publications Memorandum, Safeguards & Security Policy Panels - February 15, 2008 FAQS Sponsors and Recognized Experts Classification CommuniQu - Year: 2012

  3. Graphene-Au Nanoparticles Composite-Based Electrochemical Aptamer...

    Office of Scientific and Technical Information (OSTI)

    Subject: Inorganic, Organic, Physical, & Analytical Chemistry(37); Nanoscience & Nanotechnology(77) Analytical Chemistry; Inorganic and Physical Chemistry Word Cloud More Like This ...

  4. Graphene-Au Nanoparticles Composite-Based Electrochemical Aptamer

    Office of Scientific and Technical Information (OSTI)

    Not Provided Los Alamos National Laboratory (LANL) Oppenheimer Fellowship United States 2014-03-27 English Conference Conference: 247th ACS National Meeting & Exposition ;...

  5. Memorandum, AU-1 Clarification on the Drug Testing Custody and...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    More Documents & Publications POLICY FLASH 2015-30 Policy Flash - Recent State Initiatives on "Recreational" Marijuana use Federal Register Notice, Amending 10 CFR part 707, ...

  6. Graphene-Au Nanoparticles Composite-Based Electrochemical Aptamer...

    Office of Scientific and Technical Information (OSTI)

    Country of Publication: United States Language: English Subject: Inorganic, Organic, Physical, & Analytical Chemistry(37); Nanoscience & Nanotechnology(77) Analytical Chemistry; ...

  7. Microsoft Word - AU Funtional Area Points of Contact by Office...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Accident Investigations Andy Lawrence Andrew.lawrence@hq.doe.gov (202) 586-6740 Administrative Review (Clearance eligibility determinations) Robert Lingan Robert.lingan@hq.doe.gov ...

  8. Search for the Standard Model Higgs Boson in p anti-p Interactions with the Decay Mode H --> W+W- --> mu+nu mu-anti-nu at the D0 Experiment

    SciTech Connect (OSTI)

    Johnston, Dale Morgan; /Nebraska U.

    2010-04-01

    A search for the standard model Higgs boson in p{bar p} collisions resulting in two muons and large missing transverse energy is presented. The analysis uses 4.2 fb{sup -1} of integrated luminosity at a center-of-mass energy of {radical}s = 1.96 TeV collected between April 2002 and December 2008 with the D0 detector at the Fermilab Tevatron collider. No significant excess above the background estimation is observed and limits are derived on Higgs boson production.

  9. RF optimization and analysis of the 805-MHz cavity for the MuCool program using ACE3P

    SciTech Connect (OSTI)

    Li Zenghai; Ge Lixin; Adolphsen, Chris; Li Derun; Bowring, Daniel [SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025 (United States); Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States)

    2012-12-21

    An 805 MHz pillbox cavity tested at Fermilab's MTA facility showed significant degradation in gradient when operated in a several Tesla solenoidal magnetic field. We have used the advanced ACE3P simulation codes developed at SLAC to study the cavity dark current and multipacting characteristics to gain more insight into the gradient limitations. We also checked whether there is an optimal cavity length that minimizes the dark current impact energy. Finally, we have improved on the cavity design, significantly lowering the fields outside the beam area. These and other results are presented in this paper.

  10. Probing lepton flavour violation via neutrinoless $${\\tau \\longrightarrow 3\\mu }$$ τ → 3 μ decays with the ATLAS detector

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Aad, G.; Abbott, B.; Abdallah, J.; Abdinov, O.; Aben, R.; Abolins, M.; AbouZeid, O. S.; Abramowicz, H.; Abreu, H.; Abreu, R.; et al

    2016-04-26

    This article presents the sensitivity of the ATLAS experiment to the lepton-flavour-violating decays of τ→3μ. A method utilising the production of τ leptons via W→τν decays is used. This method is applied to the sample of 20.3 fb-1 of pp collision data at a centre-of-mass energy of 8 TeV collected by the ATLAS experiment at the LHC in 2012. No event is observed passing the selection criteria, and the observed (expected) upper limit on the τ lepton branching fraction into three muons, Br(τ→3μ), is 3.76×10-7 (3.94×10-7 ) at 90 % confidence level.

  11. Poly[bis(N,N-dimethylformamide-[kappa]O)([mu]4-naphthalene-1,5-disulfonato)magnesium(II)

    SciTech Connect (OSTI)

    Borkowski, Lauren A.; Banerjee, Debasis; Parise, John B.

    2011-08-16

    The structure of the title compound, [Mg(C{sub 10}H{sub 6}O{sub 6}S{sub 2})(C{sub 3}H{sub 7}NO){sub 2}]{sub n}, consists of MgO{sub 6} octahedra ({bar 1} symmetry) connected to naphthalene-1,5-disulfonate ligands ({bar 1} symmetry) in the equatoral plane, forming a two-dimensional network propagating parallel to (010). The coordination sphere of the Mg atom is completed by the O atoms of two N,N-dimethylformamide (DMF) molecules in the axial positions. The title compound represents the first time the naphthalene-1,5-disulfonate anion is bound directly to a Mg{sup 2+} atom. Disorder over two positions was found in the DMF molecule in a 0.518 (8):0.482 (8) ratio.

  12. An engineering-economic analysis of combined heat and power technologies in a (mu)grid application

    SciTech Connect (OSTI)

    Bailey, Owen; Ouaglal, Boubekeur; Bartholomew, Emily; Marnay, Chris; Bourassa, Norman

    2002-03-01

    This report describes an investigation at Ernesto Orlando Lawrence Berkeley National Laboratory (Berkeley Lab) of the potential for coupling combined heat and power (CHP) with on-site electricity generation to provide power and heating, and cooling services to customers. This research into distributed energy resources (DER) builds on the concept of the microgrid (mGrid), a semiautonomous grouping of power-generating sources that are placed and operated by and for the benefit of its members. For this investigation, a hypothetical small shopping mall (''Microgrid Oaks'') was developed and analyzed for the cost effectiveness of installing CHP to provide the mGrid's energy needs. A mGrid consists of groups of customers pooling energy loads and installing a combination of generation resources that meets the particular mGrid's goals. This study assumes the mGrid is seeking to minimize energy costs. mGrids could operate independently of the macrogrid (the wider power network), but they are usually assumed to be connected, through power electronics, to the macrogrid. The mGrid in this study is assumed to be interconnected to the macrogrid, and can purchase some energy and ancillary services from utility providers.

  13. THE EVOLUTION OF SOLAR FLUX FROM 0.1 nm TO 160 {mu}m: QUANTITATIVE ESTIMATES FOR PLANETARY STUDIES

    SciTech Connect (OSTI)

    Claire, Mark W.; Sheets, John; Meadows, Victoria S.; Cohen, Martin; Ribas, Ignasi; Catling, David C.

    2012-09-20

    Understanding changes in the solar flux over geologic time is vital for understanding the evolution of planetary atmospheres because it affects atmospheric escape and chemistry, as well as climate. We describe a numerical parameterization for wavelength-dependent changes to the non-attenuated solar flux appropriate for most times and places in the solar system. We combine data from the Sun and solar analogs to estimate enhanced UV and X-ray fluxes for the young Sun and use standard solar models to estimate changing visible and infrared fluxes. The parameterization, a series of multipliers relative to the modern top of the atmosphere flux at Earth, is valid from 0.1 nm through the infrared, and from 0.6 Gyr through 6.7 Gyr, and is extended from the solar zero-age main sequence to 8.0 Gyr subject to additional uncertainties. The parameterization is applied to a representative modern day flux, providing quantitative estimates of the wavelength dependence of solar flux for paleodates relevant to the evolution of atmospheres in the solar system (or around other G-type stars). We validate the code by Monte Carlo analysis of uncertainties in stellar age and flux, and with comparisons to the solar proxies {kappa}{sup 1} Cet and EK Dra. The model is applied to the computation of photolysis rates on the Archean Earth.

  14. Fixing two-nucleon weak-axial coupling L{sub 1,A} from {mu}{sup -}d capture

    SciTech Connect (OSTI)

    Chen, J.-W.; Inoue, Takashi; Ji Xiangdong; Li Yingchuan

    2005-12-15

    We calculate the muon capture rate on the deuteron to next-to-next-to-leading order in the pionless effective field theory. The result can be used to constrain the two-nucleon isovector axial coupling L{sub 1,A} to {+-}2 fm{sup 3} if the muon capture rate is measured to the 2% level. From this, one can determine the neutrino-deuteron breakup reactions and the pp fusion cross section in the sun to the same level of accuracy.

  15. Brazing open cell reticulated copper foam to stainless steel tubing with vacuum furnace brazed gold/indium alloy plating

    DOE Patents [OSTI]

    Howard, Stanley R.; Korinko, Paul S.

    2008-05-27

    A method of fabricating a heat exchanger includes brush electroplating plated layers for a brazing alloy onto a stainless steel tube in thin layers, over a nickel strike having a 1.3 .mu.m thickness. The resultant Au-18 In composition may be applied as a first layer of indium, 1.47 .mu.m thick, and a second layer of gold, 2.54 .mu.m thick. The order of plating helps control brazing erosion. Excessive amounts of brazing material are avoided by controlling the electroplating process. The reticulated copper foam rings are interference fit to the stainless steel tube, and in contact with the plated layers. The copper foam rings, the plated layers for brazing alloy, and the stainless steel tube are heated and cooled in a vacuum furnace at controlled rates, forming a bond of the copper foam rings to the stainless steel tube that improves heat transfer between the tube and the copper foam.

  16. Synthesis of bimetallic barium titanium alkoxides as precursors for electrical ceramics. Molecular structure of the new barium titanium oxide alkoxide Ba[sub 4]Ti[sub 13]([mu][sub 3]-O)[sub 12]([mu][sub 5]-O)[sub 6]([mu][sub 1]-[eta][sup 1]-OCH[sub 2]CH[sub 2]OCH[sub 3])[sub 12]([mu][sub 1],[mu][sub 3]-[eta][sup 2]-OCH[sub 2]CH[sub 2]OCH[sub 3])[sub 12

    SciTech Connect (OSTI)

    Campion, J.F.; Payne, D.A.; Chae, H.K.; Maurin, J.K.; Wilson, S.R. )

    1991-08-21

    Complex alkoxides are promising precursors for the preparation of fine ceramic powders, thin-layer devices, and fibers. Hydrolysis and condensation of alkoxides result in the formation of oligomeric structures in solution and in the eventual formation of a gel. The formation of heterometallic species can lead to chemical homogeneity at the molecular level. Although there are numerous examples of bimetallic alkoxides in the literature, less is known regarding the structure of partial hydrolysis products. A better understanding of the sol-gel processing of ceramics could result from a study of hydrolysis and polycondensation reactions in complex alkoxides. The investigation described herein has as its objective the study of the synthesis and hydrolysis of heterometallic alkoxide precursors for barium titanate ceramics. For example, BaTiO[sub 3] is used in high dielectric constant capacitor materials, and Ba[sub 4]Ti[sub 13]O[sub 30], in high-frequency resonators.

  17. Comparison of Muon Capture in Light and in Heavy Nuclei

    SciTech Connect (OSTI)

    Measday, David F.; Stocki, Trevor J.

    2007-10-26

    We have recently completed an experimental study at TRIUMF of muon capture in the following elements, N, Al, Si, Ca, Fe, Ni, I, Au, and Bi. We detected the nuclear gamma rays emitted by the product nuclei after muon capture. The energy of the gamma ray identifies the source nuclide, and thus the reaction which has occurred. Our data are of better quality, and more comprehensive than any other data set in the literature. The ({mu}{sup -},{nu}n) reaction is always dominant. In light nuclei, reactions such as ({mu}{sup -},{nu}p) and ({mu}{sup -},{nu}pn) can occur, but not for heavy nuclei. However the reverse is true for reactions such as ({mu}{sup -},{nu}3n) and ({mu}{sup -},{nu}4n), which are very rare in light nuclei, but easily detected in heavy elements. We shall discuss how such information can be useful in calculations of neutrino-nucleus interactions, and of electron-capture in supernovae.

  18. A SPITZER MIPS STUDY OF 2.5-2.0 M{sub Sun} STARS IN SCORPIUS-CENTAURUS

    SciTech Connect (OSTI)

    Chen, Christine H.; Bitner, Martin; Pecaut, Mark; Mamajek, Eric E.; Su, Kate Y. L.

    2012-09-10

    We have obtained Spitzer Space Telescope Multiband Imaging Photometer for Spitzer (MIPS) 24 {mu}m and 70 {mu}m observations of 215 nearby, Hipparcos B- and A-type common proper-motion single and binary systems in the nearest OB association, Scorpius-Centaurus. Combining our MIPS observations with those of other ScoCen stars in the literature, we estimate 24 {mu}m B+A-type disk fractions of 17/67 (25{sup +6}{sub -5}%), 36/131 (27{sup +4}{sub -4}%), and 23/95 (24{sup +5}{sub -4}%) for Upper Scorpius ({approx}11 Myr), Upper Centaurus Lupus ({approx}15 Myr), and Lower Centaurus Crux ({approx}17 Myr), respectively, somewhat smaller disk fractions than previously obtained for F- and G-type members. We confirm previous IRAS excess detections and present new discoveries of 51 protoplanetary and debris disk systems, with fractional infrared luminosities ranging from L{sub IR}/L{sub *} = 10{sup -6} to 10{sup -2} and grain temperatures ranging from T{sub gr} = 40 to 300 K. In addition, we confirm that the 24 {mu}m and 70 {mu}m excesses (or fractional infrared luminosities) around B+A-type stars are smaller than those measured toward F+G-type stars and hypothesize that the observed disk property dependence on stellar mass may be the result of a higher stellar companion fraction around B- and A-type stars at 10-200 AU. Finally, we note that the majority of the ScoCen 24 {mu}m excess sources also possess 12 {mu}m excess, indicating that Earth-like planets may be forming via collisions in the terrestrial planet zone at {approx}10-100 Myr.

  19. Gold(I) chloride adducts of 1,3-bis(di-2-pyridylphosphino)propane: synthesis, structural studies and antitumour activity

    SciTech Connect (OSTI)

    Humphreys, Anthony S.; Filipovska, Aleksandra; Berners-Price, Susan J.; Koutsantonis, George A.; Skelton, Brian W.; White, Allan H.

    2008-06-30

    The novel water soluble bidentate phosphine ligand 1,3-bis(di-2-pyridylphosphino)propane (d2pypp) has been synthesized by a convenient route involving treatment of 2-pyridyllithium with Cl{sub 2}P(CH{sub 2}){sub 3}PCl{sub 2} and isolation in crystalline form as the hydrochloride salt. The synthesis of the precursor Cl{sub 2}P(CH{sub 2}){sub 3}PCl{sub 2} has been optimized by the use of triphosgene as the chlorinating agent. The 2:1 and 1:2 AuCl:d2pypp adducts have been synthesized and characterized by NMR spectroscopy and single crystal X-ray studies, and shown to be of the form (AuCl){sub 2}({mu}-d2pypp-P,P{prime}) and Au(d2pypp-P,P{prime}){sub 2}Cl(-3.75H{sub 2}O), respectively. The latter is more lipophilic than analogous 1:2 adducts of gold(I) chloride with the diphosphine ligands 1,2-bis(di-n-pyridylphosphino)ethane (dnpype) for n = 2, 3 and 4, based on measurement of the n-octanol-water partition coefficient (log P = -0.46). A single crystal structure determination of the 1:2 Au(I) complex of the 3-pyridyl ethane ligand shows it to be of the form [Au(d3pype-P,P{prime}){sub 2}]Cl {center_dot} 5H{sub 2}O. The in vitro cytotoxic activity of [Au(d2pypp){sub 2}]Cl was assessed in human normal and cancer breast cells and selective toxicity to the cancer cells found. The significance of these results to the antitumour properties of chelated 1:2 Au(I) diphosphine complexes is discussed.

  20. Heavy-quark production and elliptic flow in Au+Au collisions at √sNN=62.4 GeV

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Adare, A.

    2015-04-28

    In this study, we present measurements of electrons and positrons from the semileptonic decays of heavy-flavor hadrons at midrapidity (|y|NN = 62.4 GeV. The data were collected in 2010 by the PHENIX experiment that included the new hadron-blind detector. The invariant yield of electrons from heavy-flavor decays is measured as a function of transverse momentum in the range 1 eT more »may be a result of the interplay between initial-state Cronin effects, final-state flow, and energy loss in medium. The v₂ of electrons from heavy-flavor decays is nonzero when averaged between 1.3 eT NN = 62.4 GeV. For 20%–40% centrality collisions, the v₂ at √sNN = 62.4 GeV is smaller than that for heavy-flavor decays at √sNN = 200 GeV. The v₂ of the electrons from heavy-flavor decay at the lower beam energy is also smaller than v₂ for pions. Both results indicate that the heavy-quarks interact with the medium formed in these collisions, but they may not be at the same level of thermalization with the medium as observed at √sNN = 200 GeV.« less

  1. Probing lepton flavour violation via neutrinoless $$$\\varvec{\\tau \\longrightarrow 3\\mu }$$$ τ ⟶ 3 μ decays with the ATLAS detector

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Aad, G.; Abbott, B.; Abdallah, J.; Abdinov, O.; Aben, R.; Abolins, M.; AbouZeid, O. S.; Abramowicz, H.; Abreu, H.; Abreu, R.; et al

    2016-04-26

    This article presents the sensitivity of the ATLAS experiment to the lepton-flavour-violating decays of τ→3μ. A method utilising the production of τ leptons via W→τν decays is used. This method is applied to the sample of 20.3 fb−1 of pp collision data at a centre-of-mass energy of 8 TeV collected by the ATLAS experiment at the LHC in 2012. No event is observed passing the selection criteria, and the observed (expected) upper limit on the τ lepton branching fraction into three muons, Br(τ→3μ), is 3.76×10−7 (3.94×10−7) at 90 % confidence level.

  2. Photomagnetic Switching of the Complex [Nd(dmf)[subscript 4](H[subscript 2]O)[subscript 3]([mu]-CN)Fe(CN)[subscript 5

    SciTech Connect (OSTI)

    Svendsen, Helle; Overgaard, Jacob; Chevallier, Marie; Collet, Eric; Iversen, Bo B.

    2009-10-21

    Single-crystal XRD experiments (see picture) reveal the excited-state structure of the photomagnetic heterobimetallic title complex. The system shows a decrease in all the iron-ligand bond lengths, suggesting that photoexcitation involves a ligand-to-metal charge transfer or a change in the superexchange coupling between the metal centers.

  3. Other Education and Outreach Resources | Critical Materials Institute

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Other Academic Alliances NNSA's Defense Science University Programs has academic alliances with three other universities: Washington State University off site link University of Nevada Las Vegas (UNLV) off site link University of Nevada Reno (UNR) off site link The current awards for other academic alliances are as follows: Title Organization; State Investigator Total Budget* Project Period Science Based Stockpile Stewardship Collaborative Research Development University of Nevada, Las Vegas;

  4. Other Academic Alliances | National Nuclear Security Administration

    National Nuclear Security Administration (NNSA)

    Other Academic Alliances NNSA's Defense Science University Programs has academic alliances with three other universities: Washington State University off site link University of Nevada Las Vegas (UNLV) off site link University of Nevada Reno (UNR) off site link The current awards for other academic alliances are as follows: Title Organization; State Investigator Total Budget* Project Period Science Based Stockpile Stewardship Collaborative Research Development University of Nevada, Las Vegas;

  5. Pantex_Operational_Health_System-_PIA.pdf

    Energy Savers [EERE]

    Packaging and Transportation News Packaging and Transportation News January 14, 2016 Ron Hafner with Lawrence Livermore National Laboratory lectures for a course in San Ramon, Calif. on packaging and transporting radioactive material. EM, University of Nevada, Reno Team on "Packaging University" A burgeoning relationship between EM and the University of Nevada, Reno (UNR) is giving new depth and breadth to a program that trains students and nuclear industry professionals in packing and

  6. DATE

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    4 SECTION A. Project Title: In situ Raman Spectroscopy to Enhance Nuclear Materials Research and Education - University of Nevada Reno SECTION B. Project Description The University of Nevada Reno proposes to purchase and install a Raman Spectrometer on the existing water loop for in situ analysis of materials to be used to characterize the surface chemistry of various alloys, understand the effect of mechanical stress on corrosion behavior of alloys, and improve nuclear education at UNR. SECTION

  7. Materials Data on ThAu2 (SG:191) by Materials Project

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Kristin Persson

    2015-02-09

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  8. Materials Data on Th(SiAu)2 (SG:139) by Materials Project

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Kristin Persson

    2014-11-02

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  9. Materials Data on Th(GeAu)2 (SG:139) by Materials Project

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Kristin Persson

    2014-11-02

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  10. Photoconductive response of a single Au nanorod coupled to LaAlO...

    Office of Scientific and Technical Information (OSTI)

    Authors: Jnawali, Giriraj ; Chen, Lu ; Huang, Mengchen 1 ; Lee, Hyungwoo ; Ryu, Sangwoo ; Podkaminer, Jacob P. ; Eom, Chang-Beom 2 ; Irvin, Patrick ; Levy, Jeremy 1 ; ...

  11. LAKESHORE AVON BR ANT-EDEN ALD EN-LANC ASTER AU BURN W SH ELDON

    U.S. Energy Information Administration (EIA) Indexed Site

    BOE Reserve Class No 2001 reserves 0.1 - 10 MBOE 10.1 - 100 MBOE 100.1 - 1000 MBOE 1000.1 - 10,000 MBOE 10,000.1 - 100,000 MBOE > 100,000 MBOE Appalachian Basin Boundary C a n a d a N Y P A N Y U S A Appalachian Basin, NY Area (Panel 1 of 7) Oil and Gas Fields By 2001 BOE

  12. LAKESHORE AVON BR ANT-EDEN ALD EN-LANC ASTER AU BURN W SH ELDON

    U.S. Energy Information Administration (EIA) Indexed Site

    Liquids Reserve Class No 2001 Liiquids Reserves 0.1 - 10 Mbbl 10.1 - 100 Mbbl 100.1 - 1000 Mbbl 1000.1 - 10,000 Mbbl Appalachian Basin Boundary C a n a d a N Y P A N Y U S A Appalachian Basin, NY Area (Panel 1 of 7) Oil and Gas Fields By 2001 Liquids

  13. Vapor Sensing Using Conjugated Molecule-Linked Au Nanoparticles in a Silica Matrix

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Dirk, Shawn M.; Howell, Stephen W.; Price, B. Katherine; Fan, Hongyou; Washburn, Cody; Wheeler, David R.; Tour, James M.; Whiting, Joshua; Simonson, R. Joseph

    2009-01-01

    Cross-linkedmore » assemblies of nanoparticles are of great value as chemiresistor-type sensors. Herein, we report a simple method to fabricate a chemiresistor-type sensor that minimizes the swelling transduction mechanism while optimizing the change in dielectric response. Sensors prepared with this methodology showed enhanced chemoselectivity for phosphonates which are useful surrogates for chemical weapons. Chemoselective sensors were fabricated using an aqueous solution of gold nanoparticles that were then cross-linked in the presence of the silica precursor, tetraethyl orthosilicate with the α -, ω -dithiolate (which is derived from the in situ deprotection of 1,4-di(Phenylethynyl- 4 ′ , 4 ″ -diacetylthio)-benzene ( 1 ) with wet triethylamine). The cross-linked nanoparticles and silica matrix were drop coated onto interdigitated electrodes having 8  μ m spacing. Samples were exposed to a series of analytes including dimethyl methylphosphonate (DMMP), octane, and toluene. A limit of detection was obtained for each analyte. Sensors assembled in this fashion were more sensitive to dimethyl methylphosphonate than to octane by a factor of 1000.« less

  14. Materials Data on Sb2(AuF6)3 (SG:14) by Materials Project

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Kristin Persson

    2015-02-09

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  15. Materials Data on CeInAu2 (SG:225) by Materials Project

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Kristin Persson

    2015-02-09

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  16. LAKESHORE AVON BR ANT-EDEN ALD EN-LANC ASTER AU BURN W SH ELDON

    U.S. Energy Information Administration (EIA) Indexed Site

    Liquids Reserve Class No 2001 Liiquids Reserves 0.1 - 10 Mbbl 10.1 - 100 Mbbl 100.1 - 1000 Mbbl 1000.1 - 10,000 Mbbl Appalachian Basin Boundary C a n a d a N Y P A N Y U S A ...

  17. LAKESHORE AVON BR ANT-EDEN ALD EN-LANC ASTER AU BURN W SH ELDON

    U.S. Energy Information Administration (EIA) Indexed Site

    BOE Reserve Class No 2001 reserves 0.1 - 10 MBOE 10.1 - 100 MBOE 100.1 - 1000 MBOE 1000.1 - 10,000 MBOE 10,000.1 - 100,000 MBOE > 100,000 MBOE Appalachian Basin Boundary C a n a d ...

  18. Self-organization of S adatoms on Au(111): √3R30° rows at...

    Office of Scientific and Technical Information (OSTI)

    Monte Carlo simulations are performed on lattice-gas models, we derived using a limited cluster expansion based on density functional theory energetics. Furthermore, models which ...

  19. Fragmentation of massive dense cores down to ? 1000 AU: Relation between fragmentation and density structure

    SciTech Connect (OSTI)

    Palau, Aina; Girart, Josep M.; Estalella, Robert; Fuente, Asuncin; Fontani, Francesco; Snchez-Monge, lvaro; Commeron, Benoit; Hennebelle, Patrick; Busquet, Gemma; Bontemps, Sylvain; Zapata, Luis A.; Zhang, Qizhou; Di Francesco, James

    2014-04-10

    In order to shed light on the main physical processes controlling fragmentation of massive dense cores, we present a uniform study of the density structure of 19 massive dense cores, selected to be at similar evolutionary stages, for which their relative fragmentation level was assessed in a previous work. We inferred the density structure of the 19 cores through a simultaneous fit of the radial intensity profiles at 450 and 850 ?m (or 1.2 mm in two cases) and the spectral energy distribution, assuming spherical symmetry and that the density and temperature of the cores decrease with radius following power-laws. Even though the estimated fragmentation level is strictly speaking a lower limit, its relative value is significant and several trends could be explored with our data. We find a weak (inverse) trend of fragmentation level and density power-law index, with steeper density profiles tending to show lower fragmentation, and vice versa. In addition, we find a trend of fragmentation increasing with density within a given radius, which arises from a combination of flat density profile and high central density and is consistent with Jeans fragmentation. We considered the effects of rotational-to-gravitational energy ratio, non-thermal velocity dispersion, and turbulence mode on the density structure of the cores, and found that compressive turbulence seems to yield higher central densities. Finally, a possible explanation for the origin of cores with concentrated density profiles, which are the cores showing no fragmentation, could be related with a strong magnetic field, consistent with the outcome of radiation magnetohydrodynamic simulations.

  20. Materials Data on La(In2Au)2 (SG:62) by Materials Project

    SciTech Connect (OSTI)

    Kristin Persson

    2015-02-09

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  1. Materials Data on Ce(In2Au)2 (SG:62) by Materials Project

    SciTech Connect (OSTI)

    Kristin Persson

    2015-02-09

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  2. Materials Data on In2Au (SG:225) by Materials Project

    SciTech Connect (OSTI)

    Kristin Persson

    2014-11-02

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  3. CO Oxidation Facilitated by Robust Surface States on Au-Covered...

    Office of Scientific and Technical Information (OSTI)

    Journal Name: Physical Review Letters Additional Journal Information: Journal Volume: 107; ... Language: English Word Cloud More Like This Free Publicly Accessible Full Text Accepted ...

  4. Magnetic doping of the golden cage cluster M@Au16¯ (M=Fe,Co...

    Office of Scientific and Technical Information (OSTI)

    Resource Relation: Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 79; Journal Issue: 3 Publisher: American Physical Society (APS) ...

  5. Materials Data on Sn4Au (SG:68) by Materials Project

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Kristin Persson

    2015-01-27

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  6. Materials Data on K3PbAu5 (SG:74) by Materials Project

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Kristin Persson

    2015-02-09

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  7. Materials Data on K(SnAu2)2 (SG:120) by Materials Project

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Kristin Persson

    2015-03-09

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  8. Materials Data on K4GaAu8 (SG:12) by Materials Project

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Kristin Persson

    2015-01-27

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  9. Materials Data on KTeAu (SG:194) by Materials Project

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Kristin Persson

    2015-02-09

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  10. Materials Data on K(InAu2)2 (SG:140) by Materials Project

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Kristin Persson

    2015-01-27

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  11. Spectral response of nanocrystalline ZnO films embedded with Au nanoparticles

    SciTech Connect (OSTI)

    Patra, Anuradha; Manivannan, A.; Kasiviswanathan, S.

    2012-10-28

    Flame sheet modeling is a common approach for the determination of flame transfer functions for prediction and modeling of thermoacoustic combustion instabilities. The dynamics of the flame-sheet model for simple flame geometries can be shown to be equivalent to a basic model of convective disturbances interacting with a steady heat release region. This framework shows that the flame transfer functions predicted by linearized flame-sheet models are the Fourier transform of the steady heat release rate profile for the flamesheet geometry transformed into Lagrangian convective time reference frame. This result is significant relative to existing flame-sheet modeling approaches in allowing the prediction of dynamic behaviors on the basis of steady information only. Multiple perturbations on the flame can be treated simply via superposition of individual perturbations. Analysis of results from these convective disturbance models illuminates the existence of two independent length scales governing the flame transfer function dynamics. Magnitude is governed by the tip-to-tail length of the flame, whereas phase is governed by the heat release rate profile center of mass calculated from the disturbance origin. The convective disturbance approach shows promise in its potential to derive flame transfer function predictions from a steady flame heat release rate profile.

  12. Materials Data on ZnAu3 (SG:64) by Materials Project

    SciTech Connect (OSTI)

    Kristin Persson

    2015-02-09

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  13. Materials Data on BaBiAu (SG:194) by Materials Project

    SciTech Connect (OSTI)

    Kristin Persson

    2015-03-19

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  14. Materials Data on BaSbAu (SG:194) by Materials Project

    SciTech Connect (OSTI)

    Kristin Persson

    2015-03-19

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  15. Materials Data on Ba4Ge20Au3 (SG:223) by Materials Project

    SciTech Connect (OSTI)

    Kristin Persson

    2015-03-08

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  16. Materials Data on CeInAu2 (SG:225) by Materials Project

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Kristin Persson

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  17. Materials Data on Sr(GaAu)2 (SG:129) by Materials Project

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Kristin Persson

    2015-01-21

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  18. Materials Data on SrAu (SG:11) by Materials Project

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Kristin Persson

    2015-03-09

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  19. Materials Data on Sr(GeAu)2 (SG:139) by Materials Project

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Kristin Persson

    2015-03-24

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  20. Materials Data on Sr3Au2 (SG:148) by Materials Project

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Kristin Persson

    2015-02-19

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations