Powered by Deep Web Technologies
Note: This page contains sample records for the topic "ia mo ar" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


1

Table 2 -Lime use and practices on Corn, major producing states, 2001 CO GA IL IN IA KS KY MI MN MO NE NY NC ND OH PA SD TX WI Area  

E-Print Network [OSTI]

Table 2 - Lime use and practices on Corn, major producing states, 2001 CO GA IL IN IA KS KY MI MN.7 Table 2 - Lime use and practices on Corn, major producing states, 2000 CO IL IN IA KS KY MI MN MO NE NY use and practices on Corn, major producing states, 1999 CO IL IN IA KS KY MI MN MO NE NC OH SD TX WI

Kammen, Daniel M.

2

Dust around Type Ia supernovae  

E-Print Network [OSTI]

Dust around Type Ia supernovae Lifan Wang 1,2 LawrenceIa. Subject headings: Supernovae: General, Dust, Extinctionline) bands for Type Ia supernovae. (a), upper panel, shows

Wang, Lifan

2005-01-01T23:59:59.000Z

3

New approaches for modeling type Ia supernovae  

E-Print Network [OSTI]

runaway in Type Ia supernovae: How to run away? oIgnition in Type Ia Supernovae. II. A Three- dimensionalnumber modeling of type Ia supernovae. I. hydrodynamics.

Zingale, Michael; Almgren, Ann S.; Bell, John B.; Day, Marcus S.; Rendleman, Charles A.; Woosley, Stan

2007-01-01T23:59:59.000Z

4

IA Blog Archive  

Office of Environmental Management (EM)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "of Energy Power.pdf11-161-LNG | Department ofHTS Cable ProjectsHistoryia/802871 IA Blog Archive en DOE and

5

IA News Archive  

Office of Environmental Management (EM)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "of Energy Power.pdf11-161-LNG | Department ofHTS Cable ProjectsHistoryia/802871 IA Blog Archive en DOE and66

6

New approaches for modeling type Ia supernovae  

E-Print Network [OSTI]

ich and J. Stein. On the thermonuclear runaway in Type IaSmall-Scale Stability of Thermonuclear Flames o in Type IaS. E. Woosley. The thermonuclear explosion of chandrasekhar

Zingale, Michael; Almgren, Ann S.; Bell, John B.; Day, Marcus S.; Rendleman, Charles A.; Woosley, Stan

2007-01-01T23:59:59.000Z

7

MO. REV. MO. MAGNETIC CLEANLINESS GUIDELINES  

E-Print Network [OSTI]

in the ALSEP Systems Engineering Magnetic Cleanliness File. #12;NO. REV. NO. ATM-865 MAGNETIC CLEANLINESS Engineering Magnetic Cleanliness File. #12;MO. REV. MO. ATM-865 MAGNETIC CLEANLINESS GUIDELINES PAGE 1 Of 3 DATE 4/6/70 The purpose

Rathbun, Julie A.

8

Ja argang 14 naJa ar / 2007  

E-Print Network [OSTI]

Ja argang 14 naJa ar / 2007 ixMATR In gesprek met marIa van der Hoeven posItIef oordeel over IndustrIal desIgn alumnIdag over duurzame energIe Magnetisme op atomaire schaal k w a r t a a l b l a d v

Franssen, Michael

9

String Landscape and Supernovae Ia  

E-Print Network [OSTI]

We present a model for the triggering of Supernovae Ia (SN Ia) by a phase transition to exact supersymmetry (susy) in the core of a white dwarf star. The model, which accomodates the data on SN Ia and avoids the problems of the standard astrophysical accretion based picture, is based on string landscape ideas and assumes that the decay of the false broken susy vacuum is enhanced at high density. In a slowly expanding susy bubble, the conversion of pairs of fermions to pairs of degenerate scalars releases a significant amount of energy which induces fusion in the surrounding normal matter shell. After cooling, the absence of degeneracy pressure causes the susy bubble to collapse to a black hole of about 0.1 solar mass or to some other stable susy object.

L. Clavelli

2011-10-09T23:59:59.000Z

10

Turbulence-Flame Interactions in Type Ia Supernovae  

E-Print Network [OSTI]

Interactions in Type Ia Supernovae A. J. Aspden 1 , J. B.involved in type Ia supernovae (SN Ia) requires the use of ?generated by RT in type Ia supernovae should obey Bolgiano-

Aspden, Andrew J; Lawrence Berkeley National Laboratory, 1 Cyclotron Road, MS 50A-1148, Berkeley, CA 94720 (Authors 1, 2 & 3); Department of Astronomy and Astrophysics, University of California at Santa Cruz, Santa Cruz, CA 95064 (Author 4); Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY 11794 (Author 5)

2008-01-01T23:59:59.000Z

11

Ideal bandpasses for type Ia supernova cosmology  

E-Print Network [OSTI]

diversity of type Ia Supernovae, in preparation. Kim, A.error in measurements of supernovae depends on a periodicABSTRACT To use type Ia supernovae as standard candles for

Davis, Tamara M.; Schmidt, Brian P.; Kim, Alex G.

2005-01-01T23:59:59.000Z

12

Simple Molybdenum(IV) Olefin Complexes of the Type Mo(NR)(X)(Y)(olefin)  

E-Print Network [OSTI]

Exposure of heptane solutions of Mo(NAr)(CHCMe2Ph)(Me2Pyr)(OAr) (1a; Ar = 2,6-diisopropylphenyl), Mo(NAr)(CHCMe3)(Me2Pyr)[OCMe(CF3)2] (1b), and Mo(NAr)(CHCMe2Ph)(Me2Pyr)(OSiPh3) (1c) to one atmosphere of ethylene for 12 h ...

Marinescu, Smaranda C.

13

Rates and progenitors of type Ia supernovae  

E-Print Network [OSTI]

Supernovae . . . . . . . . . . . . . . . . . . . .Supernovae Found 5.1 Introduction . . . . . . . . . . . .1.2 Non-Type Ia Supernovae . . . . . . . . . . . . . . . 1.3

Wood-Vasey, William Michael

2004-01-01T23:59:59.000Z

14

Type Ia Supernova Carbon Footprints  

E-Print Network [OSTI]

We present convincing evidence of unburned carbon at photospheric velocities in new observations of 5 Type Ia supernovae (SNe Ia) obtained by the Nearby Supernova Factory. These SNe are identified by examining 346 spectra from 124 SNe obtained before +2.5 d relative to maximum. Detections are based on the presence of relatively strong C II 6580 absorption "notches" in multiple spectra of each SN, aided by automated fitting with the SYNAPPS code. Four of the 5 SNe in question are otherwise spectroscopically unremarkable, with ions and ejection velocities typical of SNe Ia, but spectra of the fifth exhibits high-velocity (v > 20,000 km/s) Si II and Ca II features. On the other hand, the light curve properties are preferentially grouped, strongly suggesting a connection between carbon-positivity and broad band light curve/color behavior: Three of the 5 have relatively narrow light curves but also blue colors, and a fourth may be a dust-reddened member of this family. Accounting for signal-to-noise and phase, we ...

Thomas, R C; Aragon, C; Antilogus, P; Bailey, S; Baltay, C; Bongard, S; Buton, C; Canto, A; Childress, M; Chotard, N; Copin, Y; Fakhouri, H K; Gangler, E; Hsiao, E Y; Kerschhaggl, M; Kowalski, M; Loken, S; Nugent, P; Paech, K; Pain, R; Pecontal, E; Pereira, R; Perlmutter, S; Rabinowitz, D; Rigault, M; Rubin, D; Runge, K; Scalzo, R; Smadja, G; Tao, C; Weaver, B A; Wu, C; Brown, P J; Milne, P A

2011-01-01T23:59:59.000Z

15

Low Mach Number Modeling of Type Ia Supernovae. II. Energy Evolution  

E-Print Network [OSTI]

Number Modeling of Type Ia Supernovae. II. Energy EvolutionIa. Subject headings: supernovae: general — white dwarfs —the ignition of Type Ia supernovae (SNe Ia) is critical to

Almgren, Ann S.; Bell, John B.; Rendleman, Charles A.; Zingale, Mike

2006-01-01T23:59:59.000Z

16

Turbulent Combustion in Type Ia Supernova Models  

E-Print Network [OSTI]

We review the astrophysical modeling of type Ia supernova explosions and describe numerical methods to implement numerical simulations of these events. Some results of such simulations are discussed.

F. K. Roepke; W. Hillebrandt

2006-09-15T23:59:59.000Z

17

Theoretical cosmic Type Ia supernova rates  

E-Print Network [OSTI]

The aim of this work is the computation of the cosmic Type Ia supernova rates at very high redshifts (z>2). We adopt various progenitor models in order to predict the number of explosions in different scenarios for galaxy formation and to check whether it is possible to select the best delay time distribution model, on the basis of the available observations of Type Ia supernovae. We also computed the Type Ia supernova rate in typical elliptical galaxies of different initial luminous masses and the total amount of iron produced by Type Ia supernovae in each case. It emerges that: it is not easy to select the best delay time distribution scenario from the observational data and this is because the cosmic star formation rate dominates over the distribution function of the delay times; the monolithic collapse scenario predicts an increasing trend of the SN Ia rate at high redshifts whereas the predicted rate in the hierarchical scheme drops dramatically at high redshift; for the elliptical galaxies we note that the predicted maximum of the Type Ia supernova rate depends on the initial galactic mass. The maximum occurs earlier (at about 0.3 Gyr) in the most massive ellipticals, as a consequence of downsizing in star formation. We find that different delay time distributions predict different relations between the Type Ia supernova rate per unit mass at the present time and the color of the parent galaxies and that bluer ellipticals present higher supernova Type Ia rates at the present time.

R. Valiante; F. Matteucci; S. Recchi; F. Calura

2009-03-16T23:59:59.000Z

18

He Wehewehe no ka Papahana Kkel Laeo`o no ka `lelo a Mo`okalalelo Hawai`i a he H`ike Pehea e Ho`opihapiha ai i ka Pepa Noi Komo  

E-Print Network [OSTI]

`i a ho`omhuahua a`e i k kkou `ike no ka `lelo a mo`okalaleo Hawai`i i mau aku n ke ola. Ua ho`okumu `ia Hawai`i o n kulanui me n kula ki`eki`e. Aia ka `i`o, ka `onipa`a a me ka mhuahua `ana a`e o ia mau`e `ia aku n noi e k ana i n koina a pau i ke Kmike `Ae Komo o ka Mokuna Ha`awina Hawai`i. E ho`ouna `ia

Wiegner, Tracy N.

19

THE LOCAL HOSTS OF TYPE Ia SUPERNOVAE  

SciTech Connect (OSTI)

We use multi-wavelength, matched aperture, integrated photometry from the Galaxy Evolution Explorer (GALEX), the Sloan Digital Sky Survey, and the RC3 to estimate the physical properties of 166 nearby galaxies hosting 168 well-observed Type Ia supernovae (SNe Ia). The ultraviolet (UV) imaging of local SN Ia hosts from GALEX allows a direct comparison with higher-redshift hosts measured at optical wavelengths that correspond to the rest-frame UV. Our data corroborate well-known features that have been seen in other SN Ia samples. Specifically, hosts with active star formation produce brighter and slower SNe Ia on average, and hosts with luminosity-weighted ages older than 1 Gyr produce on average more faint, fast, and fewer bright, slow SNe Ia than younger hosts. New results include that in our sample, the faintest and fastest SNe Ia occur only in galaxies exceeding a stellar mass threshold of approx10{sup 10} M{sub sun}, leading us to conclude that their progenitors must arise in populations that are older and/or more metal rich than the general SN Ia population. A low host extinction subsample hints at a residual trend in peak luminosity with host age, after correcting for light-curve shape, giving the appearance that older hosts produce less-extincted SNe Ia on average. This has implications for cosmological fitting of SNe Ia, and suggests that host age could be useful as a parameter in the fitting. Converting host mass to metallicity and computing {sup 56}Ni mass from the supernova light curves, we find that our local sample is consistent with a model that predicts a shallow trend between stellar metallicity and the {sup 56}Ni mass that powers the explosion, but we cannot rule out the absence of a trend. We measure a correlation between {sup 56}Ni mass and host age in the local universe that is shallower and not as significant as that seen at higher redshifts. The details of the age-{sup 56}Ni mass correlations at low and higher redshift imply a luminosity-weighted age threshold of approx3 Gyr for SN Ia hosts, above which they are less likely to produce SNe Ia with {sup 56}Ni masses above approx0.5 M{sub sun}.

Neill, James D.; Martin, D. Christopher; Barlow, Tom A.; Foster, Karl; Friedman, Peter G.; Morrissey, Patrick; Wyder, Ted K. [California Institute of Technology, 1200 E. California Blvd., Pasadena, CA 91125 (United States); Sullivan, Mark [University of Oxford, Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH (United Kingdom); Howell, D. Andrew [Las Cumbres Observatory Global Telescope Network, 6740 Cortona Dr., Suite 102, Goleta, CA 93117 (United States); Conley, Alex [Department of Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto, ONM5S3H8 (Canada); Seibert, Mark; Madore, Barry F. [The Observatories of the Carnegie Institute of Washington, 813 Santa Barbara Street, Pasadena, CA, 91101 (United States); Neff, Susan G. [Laboratory for Astronomy and Solar Physics, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Schiminovich, David [Department of Astronomy, Columbia University, New York, NY 10027 (United States); Bianchi, Luciana [Center for Astrophysical Sciences, Johns Hopkins University, 3400 N. Charles St., Baltimore, MD 21218 (United States); Donas, Jose; Milliard, Bruno [Laboratoire d'Astrophysique de Marseille, BP 8, Traverse du Siphon, 13376 Marseille Cedex 12 (France); Heckman, Timothy M. [Department of Physics and Astronomy, Johns Hopkins University, Homewood Campus, Baltimore, MD 21218 (United States); Lee, Young-Wook [Center for Space Astrophysics, Yonsei University, Seoul 120-749 (Korea, Republic of); Rich, R. Michael [Department of Physics and Astronomy, University of California, Los Angeles, CA 90095 (United States)

2009-12-20T23:59:59.000Z

20

Supersoft Sources as SN Ia Progenitors  

E-Print Network [OSTI]

of the existence of supersoft X­ray sources. It is argued that SNe Ia are thermonuclear explosions of accreting C is that they represent thermonuclear disruptions of mass accreting white dwarfs (WDs). Thus, the basic ingredient

Greiner, Jochen

Note: This page contains sample records for the topic "ia mo ar" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

ETODOS NUM ERICOS EN INGENIER IA  

E-Print Network [OSTI]

CONSERVATIVOS ENERG #19; IA-MOMENTO Jos#19;e M. Goicolea Ruig#19;omez y Juan Carlos Garc#19;#16;a Orden EscuelaM #19; ETODOS NUM #19; ERICOS EN INGENIER #19; IA R. Abascal, J. Dom#19;#16;nguez y G. Bugeda (Eds.upm.es Palabras clave: Din#19;amica no lineal, mecanismos, sistemas multicuerpo exibles, energ#19;#16;a- momento

Romero, Ignacio

22

Type Ia Supernova Intrinsic Magnitude Dispersion and the Fitting of Cosmological Parameters  

E-Print Network [OSTI]

Applied to Type Ia supernovae, my strategy provides adata sets. Subject headings: Supernovae: Data Analysis andhomogeneous nature of Type Ia supernovae (SNe Ia) makes them

Kim, Alex G

2011-01-01T23:59:59.000Z

23

Verifying the Cosmological Utility of Type Ia Supernovae: Implications of a Dispersion in the Ultraviolet Spectra  

E-Print Network [OSTI]

Utility of Type Ia Supernovae: Implications of a Dispersionheadings: surveys – supernovae: general – cosmologicalparameters Introduction Supernovae of Type Ia (SNe Ia) are

2008-01-01T23:59:59.000Z

24

He H`ike no ka Ho`opihapiha `ia o ka Pepa Noi Komo no ka Papahana Ho`omkaukau Kumu `iwi `o Kahuawaiola  

E-Print Network [OSTI]

45 a `oi ma ka pae 300 a ma luna a`e paha a e k ana n koina `lelo a mo`omeheu Hawai`i e helu `ia nei`omeheu Hawai`i. 7. ka puka `ana ma ho`okahi o n papa penei: HWST 205, 471, 472, 473, 474; a i `ole ka `ae a ka `ekolu kau kona l`ihi i kkulu `ia no ka ho`omkaukau `ana i n kumu Mauli Ola Hawai`i no ka ho`ona`auao ma

Wiegner, Tracy N.

25

Nebular spectra and abundance tomography of the type Ia supernova SN 2011fe: a normal SN Ia with a stable Fe core  

E-Print Network [OSTI]

A series of optical and one near-infrared nebular spectra covering the first year of the Type Ia supernova SN 2011fe are presented and modelled. The density profile that proved best for the early optical/ultraviolet spectra, "rho-11fe", was extended to lower velocities to include the regions that emit at nebular epochs. Model rho-11fe is intermediate between the fast deflagration model W7 and a low-energy delayed-detonation. Good fits to the nebular spectra are obtained if the innermost ejecta are dominated by neutron-rich, stable Fe-group species, which contribute to cooling but not to heating. The correct thermal balance can thus be reached for the strongest [FeII] and [FeIII] lines to be reproduced with the observed ratio. The 56Ni mass thus obtained is 0.47 +/- 0.05 Mo. The bulk of 56Ni has an outermost velocity of ~8500 km/s. The mass of stable iron is 0.23 +/- 0.03 Mo. Stable Ni has low abundance, ~10^{-2} Mo. This is sufficient to reproduce an observed emission line near 7400 A. A sub-Chandrasekhar exp...

Mazzali, P A; Filippenko, A V; Garnavich, P M; Clubb, K I; Maguire, K; Pan, Y -C; Shappee, R; Silverman, J M; Benetti, S; Hachinger, S; Nomoto, K; Pian, E

2015-01-01T23:59:59.000Z

26

Closest Type Ia Supernova in Decades Solves a Cosmic Mystery  

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

PTF 11kly as it appeared in the nearby M101 galaxy. (Images: Peter Nugent) Type Ia supernovae (SN Ia's) are the extraordinarily bright and remarkably similar "standard candles"...

27

The influence of working gas pressure on interlayer mixing in magnetron-deposited Mo/Si multilayers  

SciTech Connect (OSTI)

Impact of Ar gas pressure (1-4 mTorr) on the growth of amorphous interlayers in Mo/Si multilayers deposited by magnetron sputtering was investigated by small-angle x-ray scattering ({lambda} = 0.154 nm) and methods of cross-sectional transmission electron microscopy. Some reduction of thickness of the amorphous inter-layers with Ar pressure increase was found, while composition of the layers was enriched with molybdenum. The interface modification resulted in raise of EUV reflectance of the Mo/Si multilayers.

Pershyn, Yuriy; Gullikson, Erik; Artyukov, Igor; Kondratenko, Valeriy; Sevryukova, Victoriya; Voronov, Dmitriy; Zubarev, Evgeniy; Vinogradov, Alexander

2011-08-08T23:59:59.000Z

28

Probing Cosmological Isotropy With Type IA Supernovae  

E-Print Network [OSTI]

We investigate the validity of the Cosmological Principle by mapping the cosmological parameters $H_0$ and $q_0$ through the celestial sphere. In our analysis, performed in a low-redshift regime to follow a model-independent approach, we use two compilations of type Ia Supernovae (SNe Ia), namely the Union2.1 and the JLA datasets. Firstly, we show that the angular distributions for both SNe Ia datasets are statistically anisotropic at high confidence level ($p$-value $<$ 0.0001), in particular the JLA sample. Then we find that the cosmic expansion and acceleration are mainly of dipolar type, with maximal anisotropic expansion [acceleration] pointing towards $(l,b) \\simeq (326^{\\circ},12^{\\circ})$ [$(l,b) \\simeq (174^{\\circ},27^{\\circ})$], and $(l,b) \\simeq (58^{\\circ},-60^{\\circ})$ [$(l,b) \\simeq (225^{\\circ},51^{\\circ})$] for the Union2.1 and JLA data, respectively. Secondly, we use a geometrical method to test the hypothesis that the non-uniformly distributed SNe Ia events could introduce anisotropic imp...

Bengaly, C A P; Alcaniz, J S

2015-01-01T23:59:59.000Z

29

China Today IAS 2123.001  

E-Print Network [OSTI]

China Today IAS 2123.001 Kevin Carrico Tuesdays & Thursdays 10:30 am -11:45 am Approved for Non-Western culture credit Everyone knows that China today is a "rising superpower," but the real story of China's modern history is considerably more complex. This course looks beyond the headlines to rediscover China

Oklahoma, University of

30

Comparison of Recent SnIa datasets  

E-Print Network [OSTI]

We rank the six latest Type Ia supernova (SnIa) datasets (Constitution (C), Union (U), ESSENCE (Davis) (E), Gold06 (G), SNLS 1yr (S) and SDSS-II (D)) in the context of the Chevalier-Polarski-Linder (CPL) parametrization $w(a)=w_0+w_1 (1-a)$, according to their Figure of Merit (FoM), their consistency with the cosmological constant ($\\Lambda$CDM), their consistency with standard rulers (Cosmic Microwave Background (CMB) and Baryon Acoustic Oscillations (BAO)) and their mutual consistency. We find a significant improvement of the FoM (defined as the inverse area of the 95.4% parameter contour) with the number of SnIa of these datasets ((C) highest FoM, (U), (G), (D), (E), (S) lowest FoM). Standard rulers (CMB+BAO) have a better FoM by about a factor of 3, compared to the highest FoM SnIa dataset (C). We also find that the ranking sequence based on consistency with $\\Lambda$CDM is identical with the corresponding ranking based on consistency with standard rulers ((S) most consistent, (D), (C), (E), (U), (G) least consistent). The ranking sequence of the datasets however changes when we consider the consistency with an expansion history corresponding to evolving dark energy $(w_0,w_1)=(-1.4,2)$ crossing the phantom divide line $w=-1$ (it is practically reversed to (G), (U), (E), (S), (D), (C)). The SALT2 and MLCS2k2 fitters are also compared and some peculiar features of the SDSS-II dataset when standardized with the MLCS2k2 fitter are pointed out. Finally, we construct a statistic to estimate the internal consistency of a collection of SnIa datasets. We find that even though there is good consistency among most samples taken from the above datasets, this consistency decreases significantly when the Gold06 (G) dataset is included in the sample.

J. C. Bueno Sanchez; S. Nesseris; L. Perivolaropoulos

2009-10-01T23:59:59.000Z

31

SHOCK BREAKOUT FROM TYPE Ia SUPERNOVA  

SciTech Connect (OSTI)

The mode of explosive burning in Type Ia supernovae (SNe Ia) remains an outstanding problem. It is generally thought to begin as a subsonic deflagration, but this may transition into a supersonic detonation (the delayed detonation transition, DDT). We argue that this transition leads to a breakout shock, which would provide the first unambiguous evidence that DDTs occur. Its main features are a hard X-ray flash (approx20 keV) lasting approx10{sup -2} s with a total radiated energy of approx10{sup 40} erg, followed by a cooling tail. This creates a distinct feature in the visual light curve, which is separate from the nickel decay. This cooling tail has a maximum absolute visual magnitude of M{sub V} approx -9 to -10 at approx1 day, which depends most sensitively on the white dwarf radius at the time of the DDT. As the thermal diffusion wave moves in, the composition of these surface layers may be imprinted as spectral features, which would help to discern between SN Ia progenitor models. Since this feature should accompany every SNe Ia, future deep surveys (e.g., m = 24) will see it out to a distance of approx80 Mpc, giving a maximum rate of approx60 yr{sup -1}. Archival data sets can also be used to study the early rise dictated by the shock heating (at approx20 days before maximum B-band light). A similar and slightly brighter event may also accompany core bounce during the accretion-induced collapse to a neutron star, but with a lower occurrence rate.

Piro, Anthony L.; Chang, Philip; Weinberg, Nevin N., E-mail: tpiro@astro.berkeley.ed, E-mail: pchang@astro.berkeley.ed, E-mail: nweinberg@astro.berkeley.ed [Astronomy Department and Theoretical Astrophysics Center, University of California, Berkeley, CA 94720 (United States)

2010-01-01T23:59:59.000Z

32

Type Ia Supernova Hubble Residuals and Host-Galaxy Properties  

E-Print Network [OSTI]

magnitudes of type Ia supernovae from multi-band lightsuch an analysis on the supernovae of the Nearby Supernovaheadings: distance scale, supernovae: general 1 Physics

Kim, A. G.

2014-01-01T23:59:59.000Z

33

K-corrections and spectral templates of Type Ia supernovae  

E-Print Network [OSTI]

templates of Type Ia supernovae E. Y. Hsiao 1 , A. Conleyobservations of low-redshift supernovae are less a?ected byobservations, stars: supernovae Department of Physics and

Hsiao, E. Y.

2008-01-01T23:59:59.000Z

34

Constraining Cosmic Evolution of Type Ia Supernovae  

SciTech Connect (OSTI)

We present the first large-scale effort of creating composite spectra of high-redshift type Ia supernovae (SNe Ia) and comparing them to low-redshift counterparts. Through the ESSENCE project, we have obtained 107 spectra of 88 high-redshift SNe Ia with excellent light-curve information. In addition, we have obtained 397 spectra of low-redshift SNe through a multiple-decade effort at Lick and Keck Observatories, and we have used 45 ultraviolet spectra obtained by HST/IUE. The low-redshift spectra act as a control sample when comparing to the ESSENCE spectra. In all instances, the ESSENCE and Lick composite spectra appear very similar. The addition of galaxy light to the Lick composite spectra allows a nearly perfect match of the overall spectral-energy distribution with the ESSENCE composite spectra, indicating that the high-redshift SNe are more contaminated with host-galaxy light than their low-redshift counterparts. This is caused by observing objects at all redshifts with similar slit widths, which corresponds to different projected distances. After correcting for the galaxy-light contamination, subtle differences in the spectra remain. We have estimated the systematic errors when using current spectral templates for K-corrections to be {approx}0.02 mag. The variance in the composite spectra give an estimate of the intrinsic variance in low-redshift maximum-light SN spectra of {approx}3% in the optical and growing toward the ultraviolet. The difference between the maximum-light low and high-redshift spectra constrain SN evolution between our samples to be < 10% in the rest-frame optical.

Foley, Ryan J.; Filippenko, Alexei V.; Aguilera, C.; Becker, A.C.; Blondin, S.; Challis, P.; Clocchiatti, A.; Covarrubias, R.; Davis, T.M.; Garnavich, P.M.; Jha, S.; Kirshner, R.P.; Krisciunas, K.; Leibundgut, B.; Li, W.; Matheson, T.; Miceli, A.; Miknaitis, G.; Pignata, G.; Rest, A.; Riess, A.G.; /UC, Berkeley, Astron. Dept. /Cerro-Tololo InterAmerican Obs. /Washington U., Seattle, Astron. Dept. /Harvard-Smithsonian Ctr. Astrophys. /Chile U., Catolica /Bohr Inst. /Notre Dame U. /KIPAC, Menlo Park /Texas A-M /European Southern Observ. /NOAO, Tucson /Fermilab /Chile U., Santiago /Harvard U., Phys. Dept. /Baltimore, Space Telescope Sci. /Johns Hopkins U. /Res. Sch. Astron. Astrophys., Weston Creek /Stockholm U. /Hawaii U. /Illinois U., Urbana, Astron. Dept.

2008-02-13T23:59:59.000Z

35

Category:Mason, IA | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of InspectorConcentrating SolarElectricEnergyCTBarreis aCallahanWind FarmAdd a newISGANMagnetotelluricsIA"

36

Rolling Hills (IA) | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 No revisionEnvReviewNonInvasiveExplorationUT-g Grant ofRichardton Abbey Wind Farm It isRockwall,SectorIA) Jump to:

37

Steamboat IA Geothermal Facility | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 No revisionEnvReviewNonInvasiveExplorationUT-g GrantAtlas (PACA RegionSpringviewNameGeothermal Facility JumpIA

38

Mo-Si-B Alloy Development  

SciTech Connect (OSTI)

Mo-Si-B silicides consisting of the phases {alpha}-Mo (Mo solid solution), Mo{sub 3}Si, and Mo{sub 5}SiB{sub 2} have melting points on the order of 2000 C and have potential as ultra-high temperature structural materials. Mo-Si-B alloys can be processed such that the {alpha}-Mo is present in the form of isolated particles in a silicide matrix, or as a continuous matrix ''cementing'' individual silicide particles together. The latter microstructure is similar to that of WC-Co hard metals. This paper focuses on the relationship between the topology as well as scale of the microstructure of Mo-Mo{sub 3}Si-Mo{sub 5}SiB{sub 2} alloys, and their creep strength and fracture toughness. For example, the creep strength of Mo-Si-B alloys is improved by reducing the {alpha}-Mo volume fraction and by making the {alpha}-Mo phase discontinuous. The fracture toughness is improved by increasing the {alpha}-Mo volume fraction and by making the {alpha}-Mo phase continuous. Room temperature stress intensity factors as high as 21 MPa m{sup 1/2} were obtained. The room temperature fracture toughness of Mo-Si-B alloys can also be improved by microalloying with Zr. The room temperature ductility of Mo itself can be improved by adding MgAl{sub 2}O{sub 4} spinel particles suggesting yet another way to improve the ductile phase toughening of Mo-Si-B alloys.

Schneibel, J.H.; Kruzie, J.J.; Ritchie, R.O.

2003-04-24T23:59:59.000Z

39

Plasma Redshift, Time Dilation, and Supernovas Ia  

E-Print Network [OSTI]

The measurements of the absolute magnitudes and redshifts of supernovas Ia show that conventional physics, which includes plasma redshift, fully explains the observed magnitude-redshift relation of the supernovas. The only parameter that is required is the Hubble constant, which in principle can be measured independently. The contemporary theory of the expansion of the universe (Big Bang) requires in addition to the Hubble constant several adjustable parameters, such as an initial explosion, the dark matter parameter, and a time adjustable dark energy parameter for explaining the supernova Ia data. The contemporary Big Bang theory also requires time dilation of distant events as an inherent premise. The contention is usually that the light curves of distant supernovas show or even prove the time dilation. In the present article, we challenge this assertion. We document and show that the previously reported data in fact indicate that there is no time dilation. The data reported by Riess et al. in the Astrophysical Journal in June 2004 confirm the plasma redshift, the absence of time dilation, dark matter, and dark energy.

Ari Brynjolfsson

2004-07-20T23:59:59.000Z

40

Three-dimensional numerical simulations of Rayleigh-Taylor unstable flames in type Ia supernovae  

E-Print Network [OSTI]

Unstable Flames in Type Ia Supernovae M. Zingale 1 , S. E.Subject headings: supernovae: general — white dwarfs —ame in Type Ia supernovae (SNe Ia) is well recognized (M¨

Zingale, M.; Woosley, S.E.; Rendleman, C.A.; Day, M.S.; Bell, J.B.

2005-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "ia mo ar" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Improving Type Ia Supernova Standard Candle Cosmology Measurements Using Observations of Early-Type Host Galaxies  

E-Print Network [OSTI]

Host Galaxies of Type Ia Supernovae Introduction SN Ia Hosts109 C HAPTER 1 Cosmology, Type Ia Supernovae and HostGalaxies Observations of supernovae have played a role in

Meyers, Joshua Evan

2012-01-01T23:59:59.000Z

42

Diversity of Type Ia Supernovae Imprinted in Chemical Abundances  

E-Print Network [OSTI]

A time delay of Type Ia supernova (SN Ia) explosions hinders the imprint of their nucleosynthesis on stellar abundances. However, some occasional cases give birth to stars that avoid enrichment of their chemical compositions by massive stars and thereby exhibit a SN Ia-like elemental feature including a very low [Mg/Fe] (~-1). We highlight the elemental feature of Fe-group elements for two low-Mg/Fe objects detected in nearby galaxies, and propose the presence of a class of SNe Ia that yield the low abundance ratios of [Cr,Mn,Ni/Fe]. Our novel models of chemical evolution reveal that our proposed class of SNe Ia (slow SNe Ia) is associated with ones exploding on a long timescale after their stellar birth, and gives a significant impact on the chemical enrichment in the Large Magellanic Cloud (LMC). In the Galaxy, on the other hand, this effect is unseen due to the overwhelming enrichment by the major class of SNe Ia that explode promptly (prompt SNe Ia) and eject a large amount of Fe-group elements. This nice...

Tsujimoto, Takuji

2012-01-01T23:59:59.000Z

43

Intermediate-band Photometry of Type Ia Supernovae  

E-Print Network [OSTI]

We present optical light curves of five Type Ia supernovae (2002er, 2002fk, 2003cg, 2003du, 2003fk). The photometric observations were performed in a set of intermediate-band filters. SNe 2002er, 2003du appear to be normal SN Ia events with similar light curve shapes, while SN 2003kf shows the behavior of a brighter SN Ia with slower decline rate after maximum. The light curves of SN 2003cg is unusual; they show a fast rise and dramatic decline near maximum and do not display secondary peak at longer wavelengths during 15-30 days after maximum light. This suggests that SN 2003cg is likely to be an intrinsically subluminous, 91bg-like SN Ia. Exploration of SN Ia feature lines through intermediate-band photometry is briefly discussed.

Wang, X; Zhang, T; Li, Z; Wang, Xiaofeng; Zhou, Xu; Zhang, Tianmeng; Li, Zongwei

2004-01-01T23:59:59.000Z

44

Direct numerical simulations of type Ia supernovae flames I: The landau-darrieus instability  

E-Print Network [OSTI]

Simulations of Type Ia Supernovae Flames I: The Landau-Subject headings: supernovae: general — white dwarfs —could occur in Type Ia supernovae (Niemeyer & Woosley 1997),

Bell, J.B.; Day, M.S.; Rendleman, C.A.; Woosley, S.E.; Zingale, M.

2003-01-01T23:59:59.000Z

45

DIVERSITY OF TYPE Ia SUPERNOVAE IMPRINTED IN CHEMICAL ABUNDANCES  

SciTech Connect (OSTI)

A time delay of Type Ia supernova (SN Ia) explosions hinders the imprint of their nucleosynthesis on stellar abundances. However, some occasional cases give birth to stars that avoid enrichment of their chemical compositions by massive stars and thereby exhibit an SN-Ia-like elemental feature including a very low [Mg/Fe] ( Almost-Equal-To - 1). We highlight the elemental feature of Fe-group elements for two low-Mg/Fe objects detected in nearby galaxies, and propose the presence of a class of SNe Ia that yield the low abundance ratios of [Cr, Mn, Ni/Fe]. Our novel models of chemical evolution reveal that our proposed class of SNe Ia (slow SNe Ia) is associated with ones exploding on a long timescale after their stellar birth and give a significant impact on the chemical enrichment in the Large Magellanic Cloud (LMC). In the Galaxy, on the other hand, this effect is unseen due to the overwhelming enrichment by the major class of SNe Ia that explode promptly (prompt SNe Ia) and eject a large amount of Fe-group elements. This nicely explains the different [Cr, Mn, Ni/Fe] features between the two galaxies as well as the puzzling feature seen in the LMC stars exhibiting very low Ca but normal Mg abundances. Furthermore, the corresponding channel of slow SN Ia is exemplified by performing detailed nucleosynthesis calculations in the scheme of SNe Ia resulting from a 0.8 + 0.6 M{sub Sun} white dwarf merger.

Tsujimoto, Takuji [National Astronomical Observatory of Japan, Mitaka-shi, Tokyo 181-8588 (Japan); Shigeyama, Toshikazu, E-mail: taku.tsujimoto@nao.ac.jp [Research Center for the Early Universe, Graduate School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)

2012-12-01T23:59:59.000Z

46

Electrodeposition of high Mo content Ni-Mo alloys under forced convection  

SciTech Connect (OSTI)

Bright, compact, adherent, metallic Ni-Mo alloys, containing over 48 wt % Mo have been electrodeposited from an aqueous solution. The Mo content, which is the highest achieved so far in induced codeposition of Ni-Mo, was determined by X-ray fluorescence spectroscopy. The absence of oxygen was verified by Auger electron spectroscopy. Electrodeposition experiments were performed on rotating cylinder electrodes and demonstrate that the Mo content of the alloy is strongly influenced by convective transport.

Podlaha, E.J.; Matlosz, M.; Landolt, D. (Ecole Polytechnique Federale de Lausanne, Lausanee (Switzerland). Dept. des materiaux)

1993-10-01T23:59:59.000Z

47

The Photometric Properties of Nearby Type Ia Supernovae  

E-Print Network [OSTI]

The Rise-Time Distribution of Nearby Type Ia Supernovae 3.1Highlight: The Physics of Supernovae, ed. W. Hillebrandt &1.1 Supernovae . . . . . . . . . . . . . . 1.1.1

Ganeshalingam, Mohan

2012-01-01T23:59:59.000Z

48

Single-Degenerate Type Ia Supernovae Are Preferentially Overluminous  

E-Print Network [OSTI]

Recent observational and theoretical progress has favored merging and helium-accreting sub-Chandrasekhar mass white dwarfs in the double-degenerate and the double-detonation channels, respectively, as the most promising progenitors of normal Type Ia supernovae (SNe Ia). Thus the fate of rapidly-accreting Chandrasekhar mass white dwarfs in the single-degenerate channel remains more mysterious then ever. In this paper, we clarify the nature of ignition in Chandrasekhar-mass single-degenerate SNe Ia by analytically deriving the existence of a characteristic length scale which establishes a transition from central ignitions to buoyancy-driven ignitions. Using this criterion, combined with data from three-dimensional simulations of convection and ignition, we demonstrate that the overwhelming majority of ignition events within Chandrasekhar-mass white dwarfs in the single-degenerate channel are buoyancy-driven, and consequently lack a vigorous deflagration phase. We thus infer that single-degenerate SNe Ia are gen...

Fisher, Robert

2015-01-01T23:59:59.000Z

49

CIRCUMSTELLAR ABSORPTION IN DOUBLE DETONATION TYPE Ia SUPERNOVAE  

SciTech Connect (OSTI)

Upon formation, degenerate He core white dwarfs are surrounded by a radiative H-rich layer primarily supported by ideal gas pressure. In this Letter, we examine the effect of this H-rich layer on mass transfer in He+C/O double white dwarf binaries that will eventually merge and possibly yield a Type Ia supernova (SN Ia) in the double detonation scenario. Because its thermal profile and equation of state differ from the underlying He core, the H-rich layer is transferred stably onto the C/O white dwarf prior to the He core's tidal disruption. We find that this material is ejected from the binary system and sweeps up the surrounding interstellar medium hundreds to thousands of years before the SN Ia. The close match between the resulting circumstellar medium profiles and values inferred from recent observations of circumstellar absorption in SNe Ia gives further credence to the resurgent double detonation scenario.

Shen, Ken J. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Guillochon, James [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Foley, Ryan J., E-mail: kenshen@astro.berkeley.edu [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

2013-06-20T23:59:59.000Z

50

TYPE Ia SUPERNOVAE STRONGLY INTERACTING WITH THEIR CIRCUMSTELLAR MEDIUM  

SciTech Connect (OSTI)

Owing to their utility for measurements of cosmic acceleration, Type Ia supernovae (SNe Ia) are perhaps the best-studied class of SNe, yet the progenitor systems of these explosions largely remain a mystery. A rare subclass of SNe Ia shows evidence of strong interaction with their circumstellar medium (CSM), and in particular, a hydrogen-rich CSM; we refer to them as SNe Ia-CSM. In the first systematic search for such systems, we have identified 16 SNe Ia-CSM, and here we present new spectra of 13 of them. Six SNe Ia-CSM have been well studied previously, three were previously known but are analyzed in depth for the first time here, and seven are new discoveries from the Palomar Transient Factory. The spectra of all SNe Ia-CSM are dominated by H{alpha} emission (with widths of {approx}2000 km s{sup -1}) and exhibit large H{alpha}/H{beta} intensity ratios (perhaps due to collisional excitation of hydrogen via the SN ejecta overtaking slower-moving CSM shells); moreover, they have an almost complete lack of He I emission. They also show possible evidence of dust formation through a decrease in the red wing of H{alpha} 75-100 days past maximum brightness, and nearly all SNe Ia-CSM exhibit strong Na I D absorption from the host galaxy. The absolute magnitudes (uncorrected for host-galaxy extinction) of SNe Ia-CSM are found to be -21.3 mag {<=} M{sub R} {<=} -19 mag, and they also seem to show ultraviolet emission at early times and strong infrared emission at late times (but no detected radio or X-ray emission). Finally, the host galaxies of SNe Ia-CSM are all late-type spirals similar to the Milky Way, or dwarf irregulars like the Large Magellanic Cloud, which implies that these objects come from a relatively young stellar population. This work represents the most detailed analysis of the SN Ia-CSM class to date.

Silverman, Jeffrey M. [Department of Astronomy, University of Texas, Austin, TX 78712-0259 (United States); Nugent, Peter E. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Gal-Yam, Avishay; Arcavi, Iair; Ben-Ami, Sagi [Benoziyo Center for Astrophysics, Weizmann Institute of Science, Rehovot 76100 (Israel); Sullivan, Mark [School of Physics and Astronomy, University of Southampton, Southampton SO17 1BJ (United Kingdom); Howell, D. Andrew; Graham, Melissa L. [Las Cumbres Observatory Global Telescope Network, Goleta, CA 93117 (United States); Filippenko, Alexei V.; Bloom, Joshua S.; Cenko, S. Bradley; Clubb, Kelsey I. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Cao, Yi; Horesh, Assaf; Kulkarni, Shrinivas R. [Cahill Center for Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States); Chornock, Ryan; Foley, Ryan J. [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States); Coil, Alison L. [Department of Physics, University of California, San Diego, La Jolla, CA 92093 (United States); Griffith, Christopher V. [Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802 (United States); Kasliwal, Mansi M., E-mail: jsilverman@astro.as.utexas.edu [Observatories of the Carnegie Institution of Science, Pasadena, CA 91101 (United States); and others

2013-07-01T23:59:59.000Z

51

EARLY EMISSION FROM TYPE Ia SUPERNOVAE  

SciTech Connect (OSTI)

A unique feature of deflagration-to-detonation (DDT) white dwarf explosion models of supernovae of type Ia is the presence of a strong shock wave propagating through the outer envelope. We consider the early emission expected in such models, which is produced by the expanding shock-heated outer part of the ejecta and precedes the emission driven by radioactive decay. We expand on earlier analyses by considering the modification of the pre-detonation density profile by the weak shocks generated during the deflagration phase, the time evolution of the opacity, and the deviation of the post-shock equation of state from that obtained for radiation pressure domination. A simple analytic model is presented and shown to provide an acceptable approximation to the results of one-dimensional numerical DDT simulations. Our analysis predicts a {approx}10{sup 3} s long UV/optical flash with a luminosity of {approx}1 to {approx}3 Multiplication-Sign 10{sup 39} erg s{sup -1}. Lower luminosity corresponds to faster (turbulent) deflagration velocity. The luminosity of the UV flash is predicted to be strongly suppressed at t > t{sub drop} {approx} 1 hr due to the deviation from pure radiation domination.

Rabinak, Itay; Waxman, Eli [Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot 76100 (Israel); Livne, Eli, E-mail: itay.rabinak@weizmann.ac.il [Racah Institute of Physics, Hebrew University, Jerusalem (Israel)

2012-09-20T23:59:59.000Z

52

Ar-40/Ar-39 Age Constraints for the Jaramillo Normal Subchron...  

Open Energy Info (EERE)

oxygen isotope, climate record calibration of the astronomical timescale proposed by Johnson (1982) and Shackleton et al. (1990). Ar-40Ar-39 ages of a normally magnetized...

53

Simulations of Turbulent Thermonuclear Burning in Type Ia Supernovae  

E-Print Network [OSTI]

Type Ia supernovae have recently received considerable attention because it appears that they can be used as "standard candles" to measure cosmic distances out to billions of light years away from us. Observations of type Ia supernovae seem to indicate that we are living in a universe that started to accelerate its expansion when it was about half its present age. These conclusions rest primarily on phenomenological models which, however, lack proper theoretical understanding, mainly because the explosion process, initiated by thermonuclear fusion of carbon and oxygen into heavier elements, is difficult to simulate even on supercomputers. Here, we investigate a new way of modeling turbulent thermonuclear deflagration fronts in white dwarfs undergoing a type Ia supernova explosion. Our approach is based on a level set method which treats the front as a mathematical discontinuity and allows for full coupling between the front geometry and the flow field. New results of the method applied to the problem of type Ia supernovae are obtained. It is shown that in 2-D with high spatial resolution and a physically motivated subgrid scale model for the nuclear flames numerically "converged" results can be obtained, but for most initial conditions the stars do not explode. In contrast, simulations in 3-D, do give the desired explosions and many of their properties, such as the explosion energies, lightcurves and nucleosynthesis products, are in very good agreement with observed type Ia supernovae.

W. Hillebrandt; M. Reinecke; W. Schmidt; F. K. Roepke; C. Travaglio; J. C. Niemeyer

2004-05-11T23:59:59.000Z

54

Diagnosing multiplicative error by lensing magnification of type Ia supernovae  

E-Print Network [OSTI]

Weak lensing causes spatially coherent fluctuations in flux of type Ia supernovae (SNe Ia). This lensing magnification allows for weak lensing measurement independent of cosmic shear. It is free of shape measurement errors associated with cosmic shear and can therefore be used to diagnose and calibrate multiplicative error. Although this lensing magnification is difficult to measure accurately in auto correlation, its cross correlation with cosmic shear and galaxy distribution in overlapping area can be measured to significantly higher accuracy. Therefore these cross correlations can put useful constraint on multiplicative error, and the obtained constraint is free of cosmic variance in weak lensing field. We present two methods implementing this idea and estimate their performances. We find that, with $\\sim 1$ million SNe Ia that can be achieved by the proposed D2k survey with the LSST telescope (Zhan et al. 2008), multiplicative error of $\\sim 0.5\\%$ for source galaxies at $z_s\\sim 1$ can be detected and la...

Zhang, Pengjie

2015-01-01T23:59:59.000Z

55

K-corrections and extinction corrections for Type Ia supernovae  

SciTech Connect (OSTI)

The measurement of the cosmological parameters from Type Ia supernovae hinges on our ability to compare nearby and distant supernovae accurately. Here we present an advance on a method for performing generalized K-corrections for Type Ia supernovae which allows us to compare these objects from the UV to near-IR over the redshift range 0 < z < 2. We discuss the errors currently associated with this method and how future data can improve upon it significantly. We also examine the effects of reddening on the K-corrections and the light curves of Type Ia supernovae. Finally, we provide a few examples of how these techniques affect our current understanding of a sample of both nearby and distant supernovae.

Nugent, Peter; Kim, Alex; Perlmutter, Saul

2002-05-21T23:59:59.000Z

56

SPECTROSCOPY OF TYPE Ia SUPERNOVAE BY THE CARNEGIE SUPERNOVA PROJECT  

SciTech Connect (OSTI)

This is the first release of optical spectroscopic data of low-redshift Type Ia supernovae (SNe Ia) by the Carnegie Supernova Project including 604 previously unpublished spectra of 93 SNe Ia. The observations cover a range of phases from 12 days before to over 150 days after the time of B-band maximum light. With the addition of 228 near-maximum spectra from the literature, we study the diversity among SNe Ia in a quantitative manner. For that purpose, spectroscopic parameters are employed such as expansion velocities from spectral line blueshifts and pseudo-equivalent widths (pW). The values of those parameters at maximum light are obtained for 78 objects, thus providing a characterization of SNe Ia that may help to improve our understanding of the properties of the exploding systems and the thermonuclear flame propagation. Two objects, namely, SNe 2005M and 2006is, stand out from the sample by showing peculiar Si II and S II velocities but otherwise standard velocities for the rest of the ions. We further study the correlations between spectroscopic and photometric parameters such as light-curve decline rate and color. In agreement with previous studies, we find that the pW of Si II absorption features are very good indicators of light-curve decline rate. Furthermore, we demonstrate that parameters such as pW2 (Si II 4130) and pW6 (Si II 5972) provide precise calibrations of the peak B-band luminosity with dispersions of Almost-Equal-To 0.15 mag. In the search for a secondary parameter in the calibration of peak luminosity for SNe Ia, we find a Almost-Equal-To 2{sigma}-3{sigma} correlation between B-band Hubble residuals and the velocity at maximum light of S II and Si II lines.

Folatelli, Gaston [Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU, WPI), Todai Institutes for Advanced Study, the University of Tokyo, 277-8583 Kashiwa (Japan); Morrell, Nidia; Phillips, Mark M.; Hsiao, Eric; Campillay, Abdo; Contreras, Carlos; Castellon, Sergio; Roth, Miguel [Las Campanas Observatory, Carnegie Observatories, Casilla 601, La Serena (Chile); Hamuy, Mario; Anderson, Joseph P. [Departamento de Astronomia, Universidad de Chile, Casilla 36-D, Santiago (Chile); Krzeminski, Wojtek [N. Copernicus Astronomical Center, ul. Bartycka 18, 00-716 Warszawa (Poland); Stritzinger, Maximilian [Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C (Denmark); Burns, Christopher R.; Freedman, Wendy L.; Madore, Barry F.; Murphy, David; Persson, S. E. [Observatories of the Carnegie Institution of Washington, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Prieto, Jose L. [Department of Astrophysical Sciences, Princeton University, 4 Ivy Ln., Princeton, NJ 08544 (United States); Suntzeff, Nicholas B.; Krisciunas, Kevin, E-mail: gaston.folatelli@ipmu.jp [George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy, Department of Physics and Astronomy, Texas A and M University, College Station, TX 77843 (United States); and others

2013-08-10T23:59:59.000Z

57

Very-high-order harmonic generation from Ar atoms and Ar+ ions in superintense pulsed laser  

E-Print Network [OSTI]

Very-high-order harmonic generation from Ar atoms and Ar+ ions in superintense pulsed laser fields-high-order harmonic generation HHG from Ar atoms and Ar+ ions by means of the self-interaction-free time-order harmonic generation HHG is one of the most rapidly developing topics in the field of laser-atom molecule

Chu, Shih-I

58

UV Spectroscopy of Type Ia Supernovae at Low- and High-Redshift  

E-Print Network [OSTI]

Spectroscopy of Type Ia Supernovae at Low- and High-RedshiftUV properties of Type Ia Supernovae. The low-redshift studyULDA Access Guide No. 6: Supernovae, The Netherlands: ESA

Nugent, Peter

2005-01-01T23:59:59.000Z

59

Feasibility of Measuring the Cosmological Constant [LAMBDA] and Mass Density [Omega] using Type Ia Supernovae  

E-Print Network [OSTI]

at z = 1. uncertainty for supernovae at z = 1. mR Adding theMass Density .Q Using Type Ia Supernovae A. Goobar and S.Density Q Using Type Ia Supernovae Ariel Goobar l and Saul

Goobar, A.

2008-01-01T23:59:59.000Z

60

Spectral Observations and Analyses of Low-Redshift Type Ia Supernovae  

E-Print Network [OSTI]

1.3.2 Thermonuclear Supernovae . . . . . . . . 1.4 Why WriteIa are the result of thermonuclear explosions of C/O whiteIa are the result of thermonuclear explosions of C/O white

Silverman, Jeffrey Michael

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "ia mo ar" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Nearby Supernova Factory Observations of SN 2006D: On Sporadic Carbon Signatures in Early Type Ia Supernova Spectra  

E-Print Network [OSTI]

with low volume-?lling factor. Subject headings: supernovae:general — supernovae: individual (SN 2006D)Introduction Type Ia supernovae (SNe Ia) make valuable

2006-01-01T23:59:59.000Z

62

Thermophysical Properties of U-10MO Alloy  

SciTech Connect (OSTI)

This report provides an overview of thermophysical properties of unirradiated uranium alloyed with ten weight percent molybdenum (U 10Mo), with particular focus on those material properties needed for modeling of new fuels for HPRRs (High Performance Research Reactors). The report contains both historical data available in the literature on U-10Mo, as well as more recent results conducted by the Global Threat Reduction Initiative fuel development program. The main use of the report is intended as a standard U-10Mo alloy properties reference for reactor models and simulations.

A. M. Phillips; G. S. Mickum; D. E. Burkes

2010-11-01T23:59:59.000Z

63

Innovation Academy Change of Major Form (Out of IA) College of Agricultural and Life Sciences  

E-Print Network [OSTI]

Innovation Academy Change of Major Form (Out of IA) College of Agricultural and Life Sciences Academy Change of Major Form (Out of IA) College of Agricultural and Life Sciences SECTION 3: TO BE COMPLETED BY THE INNOVATION ACADEMY ADVISER IA Adviser's Comments/Conditions (circle

Jawitz, James W.

64

HOSPITALITY AND TOURISM MANAGEMENT MAJOR Virgu1iaTech  

E-Print Network [OSTI]

Hospitality Facilities Planning and Methods I (3) Management (3) #HTM 3484 Socio-Cultural Impacts of Tourism 4414 Food and Beverage Management (Pre: HTM 3414) * #HTM 4464 Human Resources Management in HospHOSPITALITY AND TOURISM MANAGEMENT MAJOR Virgu1iaTech Panplil College of BusIness Department

Virginia Tech

65

Could there be a hole in type Ia supernovae?  

SciTech Connect (OSTI)

In the favored progenitor scenario, Type Ia supernovae (SNe Ia) arise from a white dwarf accreting material from a non-degenerate companion star. Soon after the white dwarf explodes, the ejected supernova material engulfs the companion star; two-dimensional hydrodynamical simulations by Marietta et al. (2001) show that, in the interaction, the companion star carves out a conical hole of opening angle 30-40 degrees in the supernova ejecta. In this paper we use multi-dimensional Monte Carlo radiative transfer calculations to explore the observable consequences of an ejecta-hole asymmetry. We calculate the variation of the spectrum, luminosity, and polarization with viewing angle for the aspherical supernova near maximum light. We find that the supernova looks normal from almost all viewing angles except when one looks almost directly down the hole. In the latter case, one sees into the deeper, hotter layers of ejecta. The supernova is relatively brighter and has a peculiar spectrum characterized by more highly ionized species, weaker absorption features, and lower absorption velocities. The spectrum viewed down the hole is comparable to the class of SN 1991T-like supernovae. We consider how the ejecta-hole asymmetry may explain the current spectropolarimetric observations of SNe Ia, and suggest a few observational signatures of the geometry. Finally, we discuss the variety currently seen in observed SNe Ia and how an ejecta-hole asymmetry may fit in as one of several possible sources of diversity.

Kasen, Daniel; Nugent, Peter; Thomas, R.C.; Wang, Lifan

2004-04-23T23:59:59.000Z

66

Probing the Type Ia environment with Light Echoes  

E-Print Network [OSTI]

In general, Light Echoes (LE) are beautiful, rather academical and therefore unavoidably useless phenomena. In some cases, however, they can give interesting information about the environment surrounding the exploding star. After giving a brief introduction to the subject, I describe its application to the case of Type Ia Supernovae and discuss the implications for progenitors and their location within the host galaxies.

F. Patat

2004-11-19T23:59:59.000Z

67

Signatures of Explosion Models for SN ~Ia & Cosmology  

E-Print Network [OSTI]

We give an overview of the current understanding of Type Ia supernovae relevant for their use as cosmological distance indicators. We present the physical basis to understand their homogeneity of the observed light curves and spectra and the observed correlations. SNe Ia have been well established as distance indicators on the 10 % level. However, the quest for the nature of the dark energy requires improvements in the accuracy to the 2 to 3 % level, we must understand the diversity within the SNe Ia population, and its evolution with redshift. Based on detailed models for the progenitors, explosions, light curves and spectra, we discuss signatures of thermonuclear explosions, and the implications for cosmology. We emphasize the relation between LC properties and spectra because, for local SNe~Ia, the diversity becomes apparent the combination of spectra and LCs whereas, by enlarge, we have to for high-z objects. At some examples, we show how we can actually probe the properties of the progenitor, its environment, and details of the explosion physics.

P. Hoeflich

2004-09-07T23:59:59.000Z

68

Effect of nuclear structure on Type Ia supernova nucleosynthesis  

E-Print Network [OSTI]

The relationship among nuclear structure, the weak processes in nuclei, and astrophysics becomes quite apparent in supernova explosion and nucleosynthesis studies. In this brief article, I report on progress made in the last few years on calculating electron capture and beta-decay rates in iron-group nuclei. I also report on applications of these rates to Type-Ia nucleosynthesis studies.

D. J. Dean

2000-12-08T23:59:59.000Z

69

Thermonuclear supernova models, and observations of Type Ia supernovae  

E-Print Network [OSTI]

In this paper, we review the present state of theoretical models of thermonuclear supernovae, and compare their predicitions with the constraints derived from observations of Type Ia supernovae. The diversity of explosion mechanisms usually found in one-dimensional simulations is a direct consequence of the impossibility to resolve the flame structure under the assumption of spherical symmetry. Spherically symmetric models have been successful in explaining many of the observational features of Type Ia supernovae, but they rely on two kinds of empirical models: one that describes the behaviour of the flame on the scales unresolved by the code, and another that takes account of the evolution of the flame shape. In contrast, three-dimensional simulations are able to compute the flame shape in a self-consistent way, but they still need a model for the propagation of the flame in the scales unresolved by the code. Furthermore, in three dimensions the number of degrees of freedom of the initial configuration of the white dwarf at runaway is much larger than in one dimension. Recent simulations have shown that the sensitivity of the explosion output to the initial conditions can be extremely large. New paradigms of thermonuclear supernovae have emerged from this situation, as the Pulsating Reverse Detonation. The resolution of all these issues must rely on the predictions of observational properties of the models, and their comparison with current Type Ia supernova data, including X-ray spectra of Type Ia supernova remnants.

E. Bravo; C. Badenes; D. Garcia-Senz

2004-12-07T23:59:59.000Z

70

Cosmic Supernova Rate History and Type Ia Supernova Progenitors  

E-Print Network [OSTI]

Adopting a single degenerate scenario for Type Ia supernova progenitors with the metallicity effect, we make a prediction of the cosmic supernova rate history as a composite of the supernova rates in spiral and elliptical galaxies, and compare with the recent observational data up to z ~ 0.55.

Chiaki Kobayashi; Ken'ichi Nomoto; Takuji Tsujimoto

2001-02-14T23:59:59.000Z

71

Low-Metallicity Inhibition of Type Ia Supernovae and Galactic and Cosmic Chemical Evolution  

E-Print Network [OSTI]

We introduce a metallicity dependence of Type Ia supernova (SN Ia) rate into the Galactic and cosmic chemical evolution models. In our SN Ia progenitor scenario, the accreting white dwarf (WD) blows a strong wind to reach the Chandrasekhar mass limit. If the iron abundance of the progenitors is as low as [Fe/H] 1-2, SNe Ia can be found only in the environments where the timescale of metal enrichment is sufficiently short as in starburst galaxies and ellipticals. The low-metallicity inhibition of SNe Ia can shed new light on the following issues: 1) The limited metallicity range of the SN Ia progenitors would imply that ``evolution effects'' are relatively small for the use of high redshift SNe Ia to determine the cosmological parameters. 2) WDs of halo populations are poor producers of SNe Ia, so that the WD contribution to the halo mass is not constrained from the iron abundance in the halo. 3) The abundance patterns of globular clusters and field stars in the Galactic halo lack of SN Ia signatures in spite of their age difference of several Gyrs, which can be explained by the low-metallicity inhibition of SNe Ia. 4) It could also explain why the SN Ia contamination is not seen in the damped Ly\\alpha systems for over a wide range of redshift.

Chiaki Kobayashi; Takuji Tsujimoto; Ken'ich Nomoto; Izumi Hachisu; Mariko Kato

1998-06-25T23:59:59.000Z

72

An Analysis of Department of Defense Instruction 8500.2 'Information Assurance (IA) Implementation.'  

SciTech Connect (OSTI)

The Department of Defense (DoD) provides its standard for information assurance in its Instruction 8500.2, dated February 6, 2003. This Instruction lists 157 'IA Controls' for nine 'baseline IA levels.' Aside from distinguishing IA Controls that call for elevated levels of 'robustness' and grouping the IA Controls into eight 'subject areas' 8500.2 does not examine the nature of this set of controls, determining, for example, which controls do not vary in robustness, how this set of controls compares with other such sets, or even which controls are required for all nine baseline IA levels. This report analyzes (1) the IA Controls, (2) the subject areas, and (3) the Baseline IA levels. For example, this report notes that there are only 109 core IA Controls (which this report refers to as 'ICGs'), that 43 of these core IA Controls apply without variation to all nine baseline IA levels and that an additional 31 apply with variations. This report maps the IA Controls of 8500.2 to the controls in NIST 800-53 and ITGI's CoBIT. The result of this analysis and mapping, as shown in this report, serves as a companion to 8500.2. (An electronic spreadsheet accompanies this report.)

Campbell, Philip LaRoche

2012-01-01T23:59:59.000Z

73

Type Ia Supernova Spectral Line Ratios as LuminosityIndicators  

SciTech Connect (OSTI)

Type Ia supernovae have played a crucial role in thediscovery of the dark energy, via the measurement of their light curvesand the determination of the peak brightness via fitting templates to theobserved lightcurve shape. Two spectroscopic indicators are also known tobe well correlated with peak luminosity. Since the spectroscopicluminosity indicators are obtained directly from observed spectra, theywill have different systematic errors than do measurements usingphotometry. Additionally, these spectroscopic indicators may be usefulfor studies of effects of evolution or age of the SNe~;Ia progenitorpopulation. We present several new variants of such spectroscopicindicators which are easy to automate and which minimize the effects ofnoise. We show that these spectroscopic indicators can be measured byproposed JDEM missions such as snap and JEDI.

Bongard, Sebastien; Baron, E.; Smadja, G.; Branch, David; Hauschildt, Peter H.

2005-12-07T23:59:59.000Z

74

Learning from the scatter in type Ia supernovae  

SciTech Connect (OSTI)

Type Ia Supernovae are standard candles so their mean apparent magnitude has been exploited to learn about the redshift-distance relationship. Besides intrinsic scatter in this standard candle, additional scatter is caused by gravitational magnification by large scale structure. Here we probe the dependence of this dispersion on cosmological parameters and show that information about the amplitude of clustering, {sigma}{sub 8}, is contained in the scatter. In principle, it will be possible to constrain {sigma}{sub 8} to within 5% with observations of 2000 Type Ia Supernovae. We identify three sources of systematic error - evolution of intrinsic scatter, baryon contributions to lensing, and non-Gaussianity of lensing - which will make this measurement difficult.

Dodelson, Scott [Particle Astrophysics Center, Fermi National Accelerator Laboratory, Batavia, Illinois 60510-0500 (United States); Department of Astronomy and Astrophysics, University of Chicago, Chicago, Illinois 60637-1433 (United States); Vallinotto, Alberto [Particle Astrophysics Center, Fermi National Accelerator Laboratory, Batavia, Illinois 60510-0500 (United States); Department of Physics, The University of Chicago, Chicago, Illinois 60637-1433 (United States)

2006-09-15T23:59:59.000Z

75

Prompt {gamma}-ray spectroscopy of the {sup 104}Mo and {sup 108}Mo fission fragments  

SciTech Connect (OSTI)

The level structures of the neutron-rich {sup 104}Mo and {sup 108}Mo nuclei have been investigated by observing prompt {gamma} rays emitted in the spontaneous fission of {sup 248}Cm with the EUROGAM spectrometer. Levels with spins up to 12{h_bar} have been observed and {gamma} branching obtained. The data can be satisfactorily described when {sup 104,108}Mo are considered as axially symmetric nuclei: in {sup 104}Mo, rotational bands based on the ground state, the one-phonon and the two-phonon {gamma}-vibrational states and a quasiparticle state have been observed, whereas in {sup 108}Mo the information is limited to the yrast band and the one phonon {gamma} band. {copyright} {ital 1996 The American Physical Society.}

Guessous, A.; Schulz, N.; Bentaleb, M.; Lubkiewicz, E. [Centre de Recherches Nucleaires, Institut National de Physique Nucleaire et de Physique des Particules, Centre National de la Recherche Scientifique, Universite Louis Pasteur, 67037 Strasbourg (France)] [Centre de Recherches Nucleaires, Institut National de Physique Nucleaire et de Physique des Particules, Centre National de la Recherche Scientifique, Universite Louis Pasteur, 67037 Strasbourg (France); Durell, J.L.; Pearson, C.J.; Phillips, W.R.; Shannon, J.A.; Urban, W.; Varley, B.J. [Department of Physics, University of Manchester, M13 9PL (United Kingdom)] [Department of Physics, University of Manchester, M13 9PL (United Kingdom); Ahmad, I.; Lister, C.J.; Morss, L.R.; Nash, K.L.; Williams, C.W. [Argonne National Laboratory, Argonne, Illinois 60439 (United States)] [Argonne National Laboratory, Argonne, Illinois 60439 (United States); Khazrouni, S. [Laboratoire de Physique Nucleaire Appliquee, Faculte des Sciences, Kenitra, Maroc (France)] [Laboratoire de Physique Nucleaire Appliquee, Faculte des Sciences, Kenitra, Maroc (France)

1996-03-01T23:59:59.000Z

76

Tunable MoS{sub 2} bandgap in MoS{sub 2}-graphene heterostructures  

SciTech Connect (OSTI)

Using density functional theory calculations with van der Waals corrections, we investigated how the interlayer orientation affects the structure and electronic properties of MoS{sub 2}-graphene bilayer heterostructures. Changing the orientation of graphene with respect to MoS{sub 2} strongly influences the type and the value of the electronic bandgap in MoS{sub 2}, while not significantly altering the binding energy between the layers or the interlayer spacing. We show that the physical origin of this tunable bandgap arises from variations in the S–S interplanar distance (MoS{sub 2} thickness) with the interlayer orientation, variations which are caused by electron transfer away from the Mo–S bonds.

Ebnonnasir, Abbas [Department of Mechanical Engineering and Materials Science Program, Colorado School of Mines, Golden, Colorado 80401 (United States); Department of Materials Science and Engineering, University of California Los Angeles, Los Angeles, California 90095 (United States); Narayanan, Badri; Ciobanu, Cristian V., E-mail: cciobanu@mines.edu, E-mail: kodambaka@ucla.edu [Department of Mechanical Engineering and Materials Science Program, Colorado School of Mines, Golden, Colorado 80401 (United States); Kodambaka, Suneel, E-mail: cciobanu@mines.edu, E-mail: kodambaka@ucla.edu [Department of Materials Science and Engineering, University of California Los Angeles, Los Angeles, California 90095 (United States)

2014-07-21T23:59:59.000Z

77

CARBON DEFLAGRATION IN TYPE Ia SUPERNOVA. I. CENTRALLY IGNITED MODELS  

SciTech Connect (OSTI)

A leading model for Type Ia supernovae (SNe Ia) begins with a white dwarf near the Chandrasekhar mass that ignites a degenerate thermonuclear runaway close to its center and explodes. In a series of papers, we shall explore the consequences of ignition at several locations within such dwarfs. Here we assume central ignition, which has been explored before, but is worth revisiting, if only to validate those previous studies and to further elucidate the relevant physics for future work. A perturbed sphere of hot iron ash with a radius of {approx}100 km is initialized at the middle of the star. The subsequent explosion is followed in several simulations using a thickened flame model in which the flame speed is either fixed-within the range expected from turbulent combustion-or based on the local turbulent intensity. Global results, including the explosion energy and bulk nucleosynthesis (e.g., {sup 56}Ni of 0.48-0.56 M{sub Sun }) turn out to be insensitive to this speed. In all completed runs, the energy released by the nuclear burning is adequate to unbind the star, but not enough to give the energy and brightness of typical SNe Ia. As found previously, the chemical stratification observed in typical events is not reproduced. These models produce a large amount of unburned carbon and oxygen in central low velocity regions, which is inconsistent with spectroscopic observations, and the intermediate mass elements and iron group elements are strongly mixed during the explosion.

Ma, H.; Woosley, S. E.; Malone, C. M. [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Almgren, A.; Bell, J. [Center for Computational Sciences and Engineering, Lawrence Berkeley National Lab, Berkeley, CA 94720 (United States)

2013-07-01T23:59:59.000Z

78

Theoretical Clues to the Ultraviolet Diversity of Type Ia Supernovae  

E-Print Network [OSTI]

The effect of metallicity on the observed light of Type Ia supernovae (SNe Ia) could lead to systematic errors as the absolute magnitudes of local and distant SNe Ia are compared to measure luminosity distances and determine cosmological parameters. The UV light may be especially sensitive to metallicity, though different modeling methods disagree as to the magnitude, wavelength dependence, and even the sign of the effect. The outer density structure, ^56 Ni, and to a lesser degree asphericity, also impact the UV. We compute synthetic photometry of various metallicity-dependent models and compare to UV/optical photometry from the Swift Ultra-Violet/Optical Telescope. We find that the scatter in the mid-UV to near-UV colors is larger than predicted by changes in metallicity alone and is not consistent with reddening. We demonstrate that a recently employed method to determine relative abundances using UV spectra can be done using UVOT photometry, but we warn that accurate results require an accurate model of t...

Brown, Peter J; Milne, Peter; Roming, Peter W A; Wang, Lifan

2015-01-01T23:59:59.000Z

79

The type Ia supernovae and the Hubble's constant  

E-Print Network [OSTI]

The Hubble's constant is usually surmised to be a constant; but the experiments show a large spread and conflicting estimates. According to the plasma-redshift theory, the Hubble's constant varies with the plasma densities along the line of sight. It varies then slightly with the direction and the distance to a supernova and a galaxy. The relation between the magnitudes of type Ia supernovae and their observed redshifts results in an Hubble's constant with an average value in intergalactic space of 59.44 km per s per Mpc. The standard deviation from this average value is only 0.6 km per s per Mpc, but the standard deviation in a single measurement is about 8.2 km per s per Mpc. These deviations do not include possible absolute calibration errors. The experiments show that the Hubble's constant varies with the intrinsic redshifts of the Milky Way galaxy and the host galaxies for type Ia supernovae, and that it varies with the galactic latitude. These findings support the plasma-redshift theory and contradict the contemporary big-bang theory. Together with the previously reported absence of time dilation in type Ia supernovae measurements, these findings have profound consequences for the standard cosmological theory.

Ari Brynjolfsson

2004-07-20T23:59:59.000Z

80

Chemical accelerator studies of reaction dynamics: Ar^+ + CH4 ? ArH^+ + CH3  

E-Print Network [OSTI]

, the reactions Ar+ + GH4 - ArH+ + CHs Ar+ + CD4 - ArD+ + CDs (2a) (2b) The Journal of Chemical Physics. Vol. 62. No.7. 1 April 1975 were studied over the energy range 0.4-25 eV c. m. Velocity and angular distributions of the ionic products have been...!.) Consequently, the dissociation energy Do(Ar-H+} ~ 3.90 eV, resulting in energies of 6.06 and 6.24 eV for dissociation of ArH+ into Ar+(2PS/2} + Hand Ar+(2pI/2} +H, respectively. With a value of D(H-CHs} =4.406 eV,27 the following reaction enthalpies are ob...

Wyatt, J. R.; Strattan, L. W.; Snyder, S. C.; Hierl, Peter M.

1975-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "ia mo ar" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

ARS Energy Water and Sustainability Program  

Broader source: Energy.gov [DOE]

Presentation covers the ARS Energy Water and Sustainability Program given at the Spring 2010 Federal Utility Partnership Working Group (FUPWG) meeting in Rapid City, South Dakota.

82

AR  

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

created to provide remote handling capabilities for the laboratory in its role as a nuclear testing station. In the early 1990s, the group branched into formal robotics,...

83

Wetting of metals and glasses on Mo  

SciTech Connect (OSTI)

The wetting of low melting point metals and Si-Ca-Al-Ti-O glasses on molybdenum has been investigated. The selected metals (Au, Cu, Ag) form a simple eutectic with Mo. Metal spreading occurs under nonreactive conditions without interdiffusion or ridge formation. The metals exhibit low (non-zero) contact angles on Mo but this requires temperatures higher than 1100 C in reducing atmospheres in order to eliminate a layer of adsorbed impurities on the molybdenum surface. By controlling the oxygen activity in the furnace, glass spreading can take place under reactive or nonreactive conditions. We have found that in the glass/Mo system the contact angle does not decrease under reactive conditions. In all cases, adsorption from the liquid seems to accelerate the diffusivity on the free molybdenum surface.

Saiz, Eduardo; Tomsia, Antoni P.; Saiz, Eduardo; Lopez-Esteban, Sonia; Benhassine, Mehdi; de Coninck, Joel; Rauch, Nicole; Ruehle, Manfred

2008-01-08T23:59:59.000Z

84

Domestic production of medical isotope Mo-99 moves a step closer  

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

Mo-99 Domestic production of medical isotope Mo-99 moves a step closer Irradiated uranium fuel has been recycled and reused for molybdenum-99 (Mo-99) production, with...

85

Oxidation, Reduction, and Condensation of Alcohols over (MO3)3 (M=Mo, W) Nanoclusters  

SciTech Connect (OSTI)

The reactions of deuterated methanol, ethanol, 1-propanol, 1-butanol, 2-propanol, 2-butanol and t-butanol over cyclic (MO3)3 (M = Mo, W) clusters were studied experimentally with temperature programmed desorption (TPD) and theoretically with coupled cluster CCSD(T) theory and density functional theory. The reactions of two alcohols per M3O9 cluster are required to provide agreement with experiment for D2O release, dehydrogenation and dehydration. The reaction begins with the elimination of water by proton transfers and forms an intermediate dialkoxy species which can undergo further reaction. Dehydration proceeds by a ? hydrogen transfer to a terminal M=O. Dehydrogenation takes place via an ? hydrogen transfer to an adjacent MoVI = O atom or a WVI metal center with redox involved for M = Mo and no redox for M = W. The two channels have comparable activation energies. H/D exchange to produce alcohols can take place after olefin is released or via the dialkoxy species depending on the alcohol and the cluster. The Lewis acidity of the metal center with WVI being larger than MoVI results in the increased reactivity of W3O9 over Mo3O9 for dehydrogenation and dehydration.

Fang, Zongtang; Li, Zhenjun; Kelley, Matthew S.; Kay, Bruce D.; Li, Shenggang; Hennigan, Jamie M.; Rousseau, Roger J.; Dohnalek, Zdenek; Dixon, David A.

2014-10-02T23:59:59.000Z

86

Experto Universitario Java Enterprise 2012-2013 Depto. Ciencia de la Computacin e IA  

E-Print Network [OSTI]

Experto Universitario Java Enterprise © 2012-2013 Depto. Ciencia de la Computación e IA Lenguaje Lenguaje Java Avanzado © 2012-2013 Depto. Ciencia de la Computación e IA Lenguaje Java 2 Índice. Ciencia de la Computación e IA Lenguaje Java 3 Java · Java es un lenguaje OO creado por Sun Microsystems

Escolano, Francisco

87

Experto Universitario Java Enterprise 2012-2013 Depto. Ciencia de la Computacin e IA  

E-Print Network [OSTI]

Experto Universitario Java Enterprise © 2012-2013 Depto. Ciencia de la Computación e IA Lenguaje Avanzado © 2012-2013 Depto. Ciencia de la Computación e IA Depuración y logs - 2 · El depurador de Eclipse Enterprise Lenguaje Java Avanzado © 2012-2013 Depto. Ciencia de la Computación e IA Depuración y logs - 3 El

Escolano, Francisco

88

Teor'ia de Grupos y Mec'anica Qu'antica Luis A. Seco  

E-Print Network [OSTI]

determinado por el Hamiltoniano de la energ'ia, un operador que, actuando sobre una funci'on /(x 1 ; : : : ; xTeor'ia de Grupos y Mec'anica Qu'antica Luis A. Seco Universidad de Toronto. Notas del curso; Teor'ia de Grupos y Mec'anica Cu'antica, L. Seco. U.I.M.P. La Coru~na, 27 Junio -- 1 Julio, 1994

Seco, Luis A.

89

Accelerator Production Options for 99MO  

SciTech Connect (OSTI)

Shortages of {sup 99}Mo, the most commonly used diagnostic medical isotope, have caused great concern and have prompted numerous suggestions for alternate production methods. A wide variety of accelerator-based approaches have been suggested. In this paper we survey and compare the various accelerator-based approaches.

Bertsche, Kirk; /SLAC

2010-08-25T23:59:59.000Z

90

Timescale stretch parameterization of Type Ia supernova B-band light curves  

E-Print Network [OSTI]

the light curve of Type Ia supernovae discovered by theof the high-redshift supernovae. This work was supported inobjects. Subject headings: supernovae: general – cosmology:

2001-01-01T23:59:59.000Z

91

Direct numerical simulations of type Ia supernovae flames II: The rayleigh-taylor instability  

E-Print Network [OSTI]

Weaver, T. A. 1994, in Supernovae, Les Houches, Session LIV,Simulations of Type Ia Supernovae Flames II: The Rayleigh-Subject headings: supernovae: general — white dwarfs —

Bell, J.B.; Day, M.S.; Rendleman, C.A.; Woosley, S.E.; Zingale, M.

2004-01-01T23:59:59.000Z

92

THE IMPACT OF METALLICITY ON THE RATE OF TYPE Ia SUPERNOVAE  

SciTech Connect (OSTI)

The metallicity of a star strongly affects both its evolution and the properties of the stellar remnant that results from its demise. It is generally accepted that stars with initial masses below {approx}8 M{sub Sun} leave behind white dwarfs and that some sub-population of these lead to Type Ia supernovae (SNe Ia). However, it is often tacitly assumed that metallicity has no effect on the rate of SNe Ia. We propose that a consequence of the effects of metallicity is to significantly increase the SN Ia rate in lower-metallicity galaxies, in contrast to previous expectations. This is because lower-metallicity stars leave behind higher-mass white dwarfs, which should be easier to bring to explosion. We first model SN Ia rates in relation to galaxy masses and ages alone, finding that the elevation in the rate of SNe Ia in lower-mass galaxies measured by Lick Observatory SN Search is readily explained. However, we then see that models incorporating this effect of metallicity agree just as well. Using the same parameters to estimate the cosmic SN Ia rate, we again find good agreement with data up to z Almost-Equal-To 2. We suggest that this degeneracy warrants more detailed examination of host galaxy metallicities. We discuss additional implications, including for hosts of high-z SNe Ia, the SN Ia delay time distribution, super-Chandrasekhar SNe, and cosmology.

Kistler, Matthew D. [California Institute of Technology, Mail Code 350-17, Pasadena, CA 91125 (United States); Stanek, K. Z.; Kochanek, Christopher S.; Thompson, Todd A. [Center for Cosmology and Astro-Particle Physics, Ohio State University, Columbus, OH 43210 (United States); Prieto, Jose L. [Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101 (United States)

2013-06-20T23:59:59.000Z

93

HOST GALAXY PROPERTIES AND HUBBLE RESIDUALS OF TYPE Ia SUPERNOVAE FROM THE NEARBY SUPERNOVA FACTORY  

SciTech Connect (OSTI)

We examine the relationship between Type Ia supernova (SN Ia) Hubble residuals and the properties of their host galaxies using a sample of 115 SNe Ia from the Nearby Supernova Factory. We use host galaxy stellar masses and specific star formation rates fitted from photometry for all hosts, as well as gas-phase metallicities for a subset of 69 star-forming (non-active galactic nucleus) hosts, to show that the SN Ia Hubble residuals correlate with each of these host properties. With these data we find new evidence for a correlation between SN Ia intrinsic color and host metallicity. When we combine our data with those of other published SN Ia surveys, we find the difference between mean SN Ia brightnesses in low- and high-mass hosts is 0.077 {+-} 0.014 mag. When viewed in narrow (0.2 dex) bins of host stellar mass, the data reveal apparent plateaus of Hubble residuals at high and low host masses with a rapid transition over a short mass range (9.8 {<=} log (M{sub *}/M{sub Sun }) {<=} 10.4). Although metallicity has been a favored interpretation for the origin of the Hubble residual trend with host mass, we illustrate how dust in star-forming galaxies and mean SN Ia progenitor age both evolve along the galaxy mass sequence, thereby presenting equally viable explanations for some or all of the observed SN Ia host bias.

Childress, M.; Aldering, G.; Aragon, C.; Bailey, S.; Fakhouri, H. K.; Hsiao, E. Y.; Kim, A. G.; Loken, S. [Physics Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Antilogus, P.; Bongard, S.; Canto, A.; Cellier-Holzem, F.; Guy, J. [Laboratoire de Physique Nucleaire et des Hautes Energies, Universite Pierre et Marie Curie Paris 6, Universite Paris Diderot Paris 7, CNRS-IN2P3, 4 place Jussieu, F-75252 Paris Cedex 05 (France); Baltay, C. [Department of Physics, Yale University, New Haven, CT 06250-8121 (United States); Buton, C.; Kerschhaggl, M.; Kowalski, M. [Physikalisches Institut, Universitaet Bonn, Nussallee 12, D-53115 Bonn (Germany); Chotard, N.; Copin, Y.; Gangler, E. [Universite de Lyon, F-69622, Lyon (France); Universite de Lyon 1, Villeurbanne (France); CNRS/IN2P3, Institut de Physique Nucleaire de Lyon (France); and others

2013-06-20T23:59:59.000Z

94

Multi-layered Spectral Formation in SNe Ia Around Maximum Light  

E-Print Network [OSTI]

stars: atmospheres — supernovae DISCLAIMER This document wasIntroduction Type Ia supernovæ have been used as “spanning the “normal” supernovæ blue magnitudes. Single Ion

Bongard, Sebastien

2008-01-01T23:59:59.000Z

95

High-Redshift Type Ia Supernova Rates in Galaxy Cluster and Field Environments  

E-Print Network [OSTI]

29 Candidates classified as supernovae . . . . . . . .1.1 Type Ia Supernovae as Standard Candles . . . . . . . .4.2.3 Supernovae . . . . . . . . . . . . . . . . 4.2.4

Barbary, Kyle Harris

2011-01-01T23:59:59.000Z

96

ar da regiao: Topics by E-print Network  

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

above the transition from evaporitic to continental sediments, it implies that the Fortuna evaporites Elsevier B.V. All rights reserved. Keywords: 40 Ar39 Ar; Volcanism;...

97

ar em amostras: Topics by E-print Network  

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

above the transition from evaporitic to continental sediments, it implies that the Fortuna evaporites Elsevier B.V. All rights reserved. Keywords: 40 Ar39 Ar; Volcanism;...

98

abdominalfistel syv ar: Topics by E-print Network  

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

above the transition from evaporitic to continental sediments, it implies that the Fortuna evaporites Elsevier B.V. All rights reserved. Keywords: 40 Ar39 Ar; Volcanism;...

99

ar na entrada: Topics by E-print Network  

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

above the transition from evaporitic to continental sediments, it implies that the Fortuna evaporites Elsevier B.V. All rights reserved. Keywords: 40 Ar39 Ar; Volcanism;...

100

ar expirado na: Topics by E-print Network  

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

above the transition from evaporitic to continental sediments, it implies that the Fortuna evaporites Elsevier B.V. All rights reserved. Keywords: 40 Ar39 Ar; Volcanism;...

Note: This page contains sample records for the topic "ia mo ar" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

ar acu vjum: Topics by E-print Network  

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

above the transition from evaporitic to continental sediments, it implies that the Fortuna evaporites Elsevier B.V. All rights reserved. Keywords: 40 Ar39 Ar; Volcanism;...

102

ar avaliacao da: Topics by E-print Network  

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

above the transition from evaporitic to continental sediments, it implies that the Fortuna evaporites Elsevier B.V. All rights reserved. Keywords: 40 Ar39 Ar; Volcanism;...

103

ar efter kolecystektomi: Topics by E-print Network  

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

above the transition from evaporitic to continental sediments, it implies that the Fortuna evaporites Elsevier B.V. All rights reserved. Keywords: 40 Ar39 Ar; Volcanism;...

104

Turbulence-Flame Interactions in Type Ia Supernovae  

E-Print Network [OSTI]

The large range of time and length scales involved in type Ia supernovae (SN Ia) requires the use of flame models. As a prelude to exploring various options for flame models, we consider, in this paper, high-resolution three-dimensional simulations of the small-scale dynamics of nuclear flames in the supernova environment in which the details of the flame structure are fully resolved. The range of densities examined, 1 to $8 \\times 10^7$ g cm$^{-3}$, spans the transition from the laminar flamelet regime to the distributed burning regime where small scale turbulence disrupts the flame. The use of a low Mach number algorithm facilitates the accurate resolution of the thermal structure of the flame and the inviscid turbulent kinetic energy cascade, while implicitly incorporating kinetic energy dissipation at the grid-scale cutoff. For an assumed background of isotropic Kolmogorov turbulence with an energy characteristic of SN Ia, we find a transition density between 1 and $3 \\times 10^7$ g cm$^{-3}$ where the nature of the burning changes qualitatively. By $1 \\times 10^7$ g cm$^{-3}$, energy diffusion by conduction and radiation is exceeded, on the flame scale, by turbulent advection. As a result, the effective Lewis Number approaches unity. That is, the flame resembles a laminar flame, but is turbulently broadened with an effective diffusion coefficient, $D_T \\sim u' l$, where $u'$ is the turbulent intensity and $l$ is the integral scale. For the larger integral scales characteristic of a real supernova, the flame structure is predicted to become complex and unsteady. Implications for a possible transition to detonation are discussed.

A. J. Aspden; J. B. Bell; M. S. Day; S. E. Woosley; M. Zingale

2008-11-17T23:59:59.000Z

105

SPIN-UP/SPIN-DOWN MODELS FOR TYPE Ia SUPERNOVAE  

SciTech Connect (OSTI)

In the single-degenerate scenario for Type Ia supernovae (SNe Ia), a white dwarf (WD) must gain a significant amount of matter from a companion star. Because the accreted mass carries angular momentum, the WD is likely to achieve fast spin periods, which can increase the critical mass, M{sub crit}, needed for explosion. When M{sub crit} is higher than the maximum mass achieved by the WD, the central regions of the WD must spin down before it can explode. This introduces super-Chandrasekhar single-degenerate explosions, and a delay between the completion of mass gain and the time of the explosion. Matter ejected from the binary during mass transfer therefore has a chance to become diffuse, and the explosion occurs in a medium with a density similar to that of typical regions of the interstellar medium. Also, either by the end of the WD's mass increase or else by the time of explosion, the donor may exhaust its stellar envelope and become a WD. This alters, generally diminishing, explosion signatures related to the donor star. Nevertheless, the spin-up/spin-down model is highly predictive. Prior to explosion, progenitors can be super-M{sub Ch} WDs in either wide binaries with WD companions or cataclysmic variables. These systems can be discovered and studied through wide-field surveys. Post-explosion, the spin-up/spin-down model predicts a population of fast-moving WDs, low-mass stars, and even brown dwarfs. In addition, the spin-up/spin-down model provides a paradigm which may be able to explain both the similarities and the diversity observed among SNe Ia.

Stefano, R. Di [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Voss, R. [Department of Astrophysics/IMAPP, Radboud University Nijmegen, P.O. Box 9010, NL-6500 GL Nijmegen (Netherlands); Claeys, J. S. W. [Sterrekundig Instituut, Universiteit Utrecht, P.O. Box 800000, 3508 TA Utrecht (Netherlands)

2011-09-01T23:59:59.000Z

106

Reflections on Reflexions: I. Light Echoes in Type Ia Supernovae  

E-Print Network [OSTI]

In the last ten years, observational evidences about a possible connection between Type Ia Supernovae (SNe) properties and the environment where they explode have been steadily growing. In this paper I discuss, from a theoretical point of view but with an observer's perspective, the usage of light echoes (LEs) to probe the CSM around SNe of Type Ia since, in principle, they give us a unique opportunity of getting a three-dimensional description of the SN environment. In turn, this can be used to check the often suggested association of some Ia's with dusty/star forming regions, which would point to a young population for the progenitors. After giving a brief introduction to the LE phenomenon in single scattering approximation, I derive analytical and numerical solutions for the optical light and colour curves for a few simple dust geometries. A fully 3D multiple scattering treatment has also been implemented in a Monte Carlo code, which I have used to investigate the effects of multiple scattering. In particular, I have explored in detail the LE colour dependency from time and dust distribution, since this is a promising tool to determine the dust density and derive the effective presence of multiple scattering from the observed properties. Finally, again by means of Monte Carlo simulations, I have studied the effects of multiple scattering on the LE linear polarization, analyzing the dependencies from the dust parameters and geometry. Both the analytical formalism and MC codes described in this paper can be used for any LE for which the light curve of the central source is known.

F. Patat

2004-09-28T23:59:59.000Z

107

Tension in the Recent Type Ia Supernovae Datasets  

E-Print Network [OSTI]

In the present work, we investigate the tension in the recent Type Ia supernovae (SNIa) datasets Constitution and Union. We show that they are in tension not only with the observations of the cosmic microwave background (CMB) anisotropy and the baryon acoustic oscillations (BAO), but also with other SNIa datasets such as Davis and SNLS. Then, we find the main sources responsible for the tension. Further, we make this more robust by employing the method of random truncation. Based on the results of this work, we suggest two truncated versions of the Union and Constitution datasets, namely the UnionT and ConstitutionT SNIa samples, whose behaviors are more regular.

Hao Wei

2010-04-07T23:59:59.000Z

108

Closest Type Ia Supernova in Decades Solves a Cosmic Mystery  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation Proposed New SubstationClean Communities of WesternVailCloistered JuneLabClosest Type Ia

109

Development of CaMoO4 crystal scintillators for double beta decay experiment with 100-Mo  

E-Print Network [OSTI]

Energy resolution, alpha/beta ratio, pulse-shape discrimination for gamma rays and alpha particles, temperature dependence of scintillation properties, and radioactive contamination were studied with CaMoO4 crystal scintillators. A high sensitivity experiment to search for neutrinoless double beta decay of 100-Mo by using CaMoO4 scintillators is discussed.

A. N. Annenkov; O. A. Buzanov; F. A. Danevich; A. Sh. Georgadze; S. K. Kim; H. J. Kim; Y. D. Kim; V. V. Kobychev; V. N. Kornoukhov; M. Korzhik; J. I. Lee; O. Missevitch; V. M. Mokina; S. S. Nagorny; A. S. Nikolaiko; D. V. Poda; R. B. Podviyanuk; D. J. Sedlak; O. G. Shkulkova; J. H. So; I. M. Solsky; V. I. Tretyak; S. S. Yurchenko

2007-07-10T23:59:59.000Z

110

E-Print Network 3.0 - ar gas filled Sample Search Results  

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

and the origin of carbonatites Summary: gas abundance ratios (for example HeAr and CO2 Ar), which change upon degassing owing to solubility... 36 Ar against 40 Ar36 Ar for...

111

Processing, Microstructure, and Properties of Multiphase Mo Silicide Alloys  

SciTech Connect (OSTI)

Multiphase Mo silicide alloys containing T2 (Mo{sub 5}SiB{sub 2}), Mo{sub 3}Si and Mo phases where prepared by both melting and casting (M and C) and powder metallurgical (PM) processes. Glassy phases are observed in PM materials but not in M and C materials. Microstructural studies indicate that the primary phase is Mo-rich solid solution in alloys containing {le}(9.4Si+13.8B, at. %) and T2 in alloys with {ge}(9.8Si+14.6B). An eutectic composition is estimated to be close to Mo-9.6Si-14.2B. The mechanical properties of multiphase silicide alloys were determined by hardness, tensile and bending tests at room temperature. The multiphase alloy MSB-18 (Mo-9.4Si-13.8B) possesses a flexure strength distinctly higher than that of MoSi{sub 2} and other Mo{sub 5}Si{sub 3} silicide alloys containing no Mo particles. Also, MSB-18 is tougher than MoSi{sub 2} by a factor of 4.

Heatherly, L.; Liu, C.T.; Schneibel, J.H.

1998-11-30T23:59:59.000Z

112

Modelos Matem'aticos Discretos Gu'ia de Controles Resueltos con Indicaciones  

E-Print Network [OSTI]

estudiantes de la carrera de Ingenier'ia Civil Matem'atica (los cuales sol'ian tomarlo durante su sexto para los estudiantes de la carrera de Ingenier'ia Civil Matem'atica (pero ahora se recomienda que el

Rapaport, Iván

113

Type Ia supernova rate studies from the SDSS-II Supernova Study  

SciTech Connect (OSTI)

The author presents new measurements of the type Ia SN rate from the SDSS-II Supernova Survey. The SDSS-II Supernova Survey was carried out during the Fall months (Sept.-Nov.) of 2005-2007 and discovered {approx} 500 spectroscopically confirmed SNe Ia with densely sampled (once every {approx} 4 days), multi-color light curves. Additionally, the SDSS-II Supernova Survey has discovered several hundred SNe Ia candidates with well-measured light curves, but without spectroscopic confirmation of type. This total, achieved in 9 months of observing, represents {approx} 15-20% of the total SNe Ia discovered worldwide since 1885. The author describes some technical details of the SN Survey observations and SN search algorithms that contributed to the extremely high-yield of discovered SNe and that are important as context for the SDSS-II Supernova Survey SN Ia rate measurements.

Dilday, Benjamin; /Chicago U.

2008-08-01T23:59:59.000Z

114

Analytical Expressions For Light-Curves Of Ordinary And Superluminous Supernovae Type Ia  

E-Print Network [OSTI]

Ordinary supernovae of type Ia (SNeIa) may be produced by the thermonuclear explosion of white dwarfs (WDs), which after their nascence in proto-planetary nebulae accrete fall-back matter and approach the Chandrasekhar mass limit. If the detonation continues into the fall-back layer and/or if the SNIa debris collide with it, they may produce a super Chandrasekhar SNIa. A few underlying physical assumptions of such model yield a very simple master formula that reproduces quite well the bolometric light-curves of both ordinary and supeluminous SNeIa. Other main properties of SNeIa, including the empirical 'brighter-slower' Philipps' relation that was used to standardize ordinary SNeIa as distance indicators and led to the discovery of the accelerating expansion of the universe are also reproduced.

Shlomo Dado; Arnon Dar

2014-02-06T23:59:59.000Z

115

40Ar/39Ar Geochronology of Post-Valles Caldera Rhyolites, Jemez...  

Open Energy Info (EERE)

during which rhyolite domes, flows, and pyroclastic rocks were emplaced from ring fracture vents. Previously, ages were based on limited K-Ar dating and stratigraphic...

116

Measurement of Omega_m, Omega_Lambda from a blind analysis of Type Ia supernovae with CMAGIC: Using color information to verify the acceleration of the Universe  

E-Print Network [OSTI]

analysis of Type Ia supernovae with CMAGIC: Using colorof 21 high redshift supernovae using a new technique (lightcurves of Type Ia supernovae, ?rst introduced in Wang

2006-01-01T23:59:59.000Z

117

Polarisation spectral synthesis for Type Ia supernova explosion models  

E-Print Network [OSTI]

We present a Monte Carlo radiative transfer technique for calculating synthetic spectropolarimetry for multi-dimensional supernova explosion models. The approach utilises "virtual-packets" that are generated during the propagation of the Monte Carlo quanta and used to compute synthetic observables for specific observer orientations. Compared to extracting synthetic observables by direct binning of emergent Monte Carlo quanta, this virtual-packet approach leads to a substantial reduction in the Monte Carlo noise. This is vital for calculating synthetic spectropolarimetry (since the degree of polarisation is typically very small) but also useful for calculations of light curves and spectra. We first validate our approach via application of an idealised test code to simple geometries. We then describe its implementation in the Monte Carlo radiative transfer code ARTIS and present test calculations for simple models for Type Ia supernovae. Specifically, we use the well-known one-dimensional W7 model to verify tha...

Bulla, M; Kromer, M

2015-01-01T23:59:59.000Z

118

DOE - Office of Legacy Management -- Titus Metals - IA 04  

Office of Legacy Management (LM)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarlyEnergyDepartment ofDepartment ofof EnergyYou areDowntown Site - MO 02SuttonTennesseePlant -Titus

119

HOST GALAXIES OF TYPE Ia SUPERNOVAE FROM THE NEARBY SUPERNOVA FACTORY  

SciTech Connect (OSTI)

We present photometric and spectroscopic observations of galaxies hosting Type Ia supernovae (SNe Ia) observed by the Nearby Supernova Factory. Combining Galaxy Evolution Explorer (GALEX) UV data with optical and near-infrared photometry, we employ stellar population synthesis techniques to measure SN Ia host galaxy stellar masses, star formation rates (SFRs), and reddening due to dust. We reinforce the key role of GALEX UV data in deriving accurate estimates of galaxy SFRs and dust extinction. Optical spectra of SN Ia host galaxies are fitted simultaneously for their stellar continua and emission lines fluxes, from which we derive high-precision redshifts, gas-phase metallicities, and H{alpha}-based SFRs. With these data we show that SN Ia host galaxies present tight agreement with the fiducial galaxy mass-metallicity relation from Sloan Digital Sky Survey (SDSS) for stellar masses log(M{sub *}/M{sub Sun }) > 8.5 where the relation is well defined. The star formation activity of SN Ia host galaxies is consistent with a sample of comparable SDSS field galaxies, though this comparison is limited by systematic uncertainties in SFR measurements. Our analysis indicates that SN Ia host galaxies are, on average, typical representatives of normal field galaxies.

Childress, M.; Aldering, G.; Aragon, C.; Bailey, S.; Fakhouri, H. K.; Hsiao, E. Y.; Kim, A. G.; Loken, S. [Physics Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Antilogus, P.; Bongard, S.; Canto, A.; Cellier-Holzem, F.; Guy, J. [Laboratoire de Physique Nucleaire et des Hautes Energies, Universite Pierre et Marie Curie Paris 6, Universite Paris Diderot Paris 7, CNRS-IN2P3, 4 place Jussieu, F-75252 Paris Cedex 05 (France); Baltay, C. [Department of Physics, Yale University, New Haven, CT 06250-8121 (United States); Buton, C.; Kerschhaggl, M.; Kowalski, M. [Physikalisches Institut, Universitaet Bonn, Nussallee 12, D-53115 Bonn (Germany); Chotard, N.; Copin, Y.; Gangler, E. [Universite de Lyon, F-69622, Lyon (France); Universite de Lyon 1, Villeurbanne (France); CNRS/IN2P3, Institut de Physique Nucleaire de Lyon (France); and others

2013-06-20T23:59:59.000Z

120

Type Ia Supernovae Rates and Galaxy Clustering from the CFHT Supernova Legacy Survey  

E-Print Network [OSTI]

The Canada-France-Hawaii Telescope Supernova Legacy Survey (SNLS) has created a large homogeneous database of intermediate redshift (0.2 rates, properties, and host galaxy star formation rates. The SNLS SN Ia database has now been combined with a photometric redshift galaxy catalog and an optical galaxy cluster catalog to investigate the possible influence of galaxy clustering on the SN Ia rate, over and above the expected effect due to the dependence of SFR on clustering through the morphology-density relation. We identify three cluster SNe Ia, plus three additional possible cluster SNe Ia, and find the SN Ia rate per unit mass in clusters at intermediate redshifts is consistent with the rate per unit mass in field early-type galaxies and the SN Ia cluster rate from low redshift cluster targeted surveys. We also find the number of SNe Ia in cluster environments to be within a factor of two of expectations from the two component SNIa rate model.

M. L. Graham; C. J. Pritchet; M. Sullivan; S. D. J. Gwyn; J. D. Neill; E. Y. Hsiao; P. Astier; D. Balam; C. Balland; S. Basa; R. G. Carlberg; A. Conley; D. Fouchez; J. Guy; D. Hardin; I. M. Hook; D. A. Howell; R. Pain; K. Perrett; N. Regnault; S. Baumont; J. Le Du; C. Lidman; S. Perlmutter; P. Ripoche; N. Suzuki; E. S. Walker; T. Zhang

2008-01-31T23:59:59.000Z

Note: This page contains sample records for the topic "ia mo ar" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Stellar Populations and the White Dwarf Mass Function: Connections To Supernova Ia Luminosities  

E-Print Network [OSTI]

We discuss the luminosity function of SNe Ia under the assumption that recent evidence for dispersion in this standard candle is related to variations in the white dwarf mass function (WDMF) in the host galaxies. We develop a simple parameterization of the WDMF as a function of age of a stellar population and apply this to galaxies of different morphological types. We show that this simplified model is consistent with the observed WDMF of Bergeron et al. (1992) for the solar neighborhood. Our simple models predict that WDMF variations can produce a range of more than 1.8 mag in M$_B$(SN Ia), which is comparable to the observed value using the data of Phillips (1993) and van den Bergh (1996). We also predict a galaxy type dependence of M$_B$(SN Ia) under standard assumptions of the star formation history in these galaxies and show that M$_B$(SN Ia) can evolve with redshift. In principle both evolutionary and galaxy type corrections should be applied to recover the intrinsic range of M$_B$(SN Ia) from the observed values. Our current inadequate knowledge of the star formation history of galaxies coupled with poor physical understanding of the SN Ia mechanism makes the reliable estimation of these corrections both difficult and controversial. The predictions of our models combined with the observed galaxy and redshift correlations may have the power to discriminate between the Chandrasekhar and the sub-Chandrasekhar progenitor scenarios for SNe Ia.

Ted von Hippel; G. D. Bothun; R. A. Schommer

1997-06-11T23:59:59.000Z

122

Neutron Hole States of Mo-93,95  

E-Print Network [OSTI]

I I I0 IO 20 3040 50 60 0 I I I I I I IO 20 30 40 5Q 60 IO 2- 0 I I I lo 20 X) 40 50 60 I j I I I l 0 lo 20 30 4050 60 8, .(deg) 8,~. (deg) {deg) {deg) FIG. 2. Angular distributions for the +Mo(P, d)93Mo reaction. The errors sho....20 l X=2 0.769 2=4 0.8l6 2=2 Mo(d, t) Mo l IGO= P IQ IO? IG 10 IQ 10 IGO? IQ I I I I l.092 2=2+4 = IO IQ)- l.674 All the angular distributions obtained along mith the D%'BA fits for the states analyzed in the "Mo(d, t)9'Mo...

Bindal, P. K.; Youngblood, David H.; Kozub, R. L.

1977-01-01T23:59:59.000Z

123

Tension and Systematics in the Gold06 SnIa Dataset  

E-Print Network [OSTI]

The Gold06 SnIa dataset recently released in astro-ph/0611572 consists of five distinct subsets defined by the group or instrument that discovered and analyzed the corresponding data. These subsets are: the SNLS subset (47 SnIa), the HST subset (30 SnIa), the HZSST subset (41 SnIa), the SCP subset (26 SnIa) and the Low Redshift (LR) subset (38 SnIa). These subsets sum up to the 182 SnIa of the Gold06 dataset. We use Monte-Carlo simulations to study the statistical consistency of each one of the above subsets with the full Gold06 dataset. In particular, we compare the best fit $w(z)$ parameters (w_0,w_1) obtained by subtracting each one of the above subsets from the Gold06 dataset (subset truncation), with the corresponding best fit parameters (w^r_0,w^r_1) obtained by subtracting the same number of randomly selected SnIa from the same redshift range of the Gold06 dataset (random truncation). We find that the probability for (w^r_0,w^r_1)=(w_0,w_1) is large for the Gold06 minus SCP (Gold06-SCP) truncation but is less than 5% for the Gold06-SNLS, Gold06-HZSST and Gold06-HST truncations. This result implies that the Gold06 dataset is not statistically homogeneous. By comparing the values of the best fit (w_0,w_1) for each subset truncation we find that the tension among subsets is such that the SNLS and HST subsets are statistically consistent with each other and `pull' towards LCDM (w_0=-1,w_1=0) while the HZSST subset is statistically distinct and strongly `pulls' towards a varying w(z) crossing the line $w=-1$ from below (w_00). We also isolate six SnIa that are mostly responsible for this behavior of the HZSST subset.

S. Nesseris; L. Perivolaropoulos

2007-01-09T23:59:59.000Z

124

Mo Year Report Period: EIA ID NUMBER:  

Gasoline and Diesel Fuel Update (EIA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) " ,"Click worksheet9,1,50022,3,,,,6,1,,781 2,328 2,683DieselValuesEIA-782A and EIA-782B:0 U.S. Energy1‹Mo

125

MoRu/Be multilayers for extreme ultraviolet applications  

DOE Patents [OSTI]

High reflectance, low intrinsic roughness and low stress multilayer systems for extreme ultraviolet (EUV) lithography comprise amorphous layers MoRu and crystalline Be layers. Reflectance greater than 70% has been demonstrated for MoRu/Be multilayers with 50 bilayer pairs. Optical throughput of MoRu/Be multilayers can be 30-40% higher than that of Mo/Be multilayer coatings. The throughput can be improved using a diffusion barrier to make sharper interfaces. A capping layer on the top surface of the multilayer improves the long-term reflectance and EUV radiation stability of the multilayer by forming a very thin native oxide that is water resistant.

Bajt, Sasa C. (Livermore, CA); Wall, Mark A. (Stockton, CA)

2001-01-01T23:59:59.000Z

126

Catalytic Properties of Supported MoO3 Catalysts for Oxidative Dehydrogenation of Propane  

E-Print Network [OSTI]

Catalytic Properties of Supported MoO3 Catalysts for Oxidative Dehydrogenation of Propane Kaidong The effects of MoOx structure on propane oxidative dehydrogenation (ODH) rates and selectivity were examined with those obtained on MoOx/ZrO2. On MoOx/Al2O3 catalysts, propane turnover rate increased with increasing Mo

Iglesia, Enrique

127

, SEYMOUR AND MacGREGOR COGNlTlYb NEUROPSYCHOLOGY. IdyslexIa. Brain. 102. 4363.  

E-Print Network [OSTI]

.T. (1980) Word-form dyslexIa. Brain. 102. 4363. REFERENCENOTES On Reducing Language to Biology I. Holmes. J. M. (1973) Dyslexia: a lIeurolinguistic study 0/ traumatic and developmental disorders 0/ reading

Mehler, Jacques

128

Quantitative comparison between Type Ia supernova spectra at low and high redshifts: A case study  

E-Print Network [OSTI]

Highlight - The Physics of Supernovae, ESO/MPA/MPE Workshop,Evolution in high-redshift supernovae Fig. 8 “Ca ii H&K”SN 1991T/SN 1999aa-like supernovae. 1. Introduction Type Ia

Garavini, G.; Supernova Cosmology Project

2008-01-01T23:59:59.000Z

129

Constructing a cosmological model-independent Hubble diagram of type Ia supernovae with cosmic chronometers  

E-Print Network [OSTI]

We apply two methods to reconstruct the Hubble parameter $H(z)$ as a function of redshift from 15 measurements of the expansion rate obtained from age estimates of passively evolving galaxies. These reconstructions enable us to derive the luminosity distance to a certain redshift $z$, calibrate the light-curve fitting parameters accounting for the (unknown) intrinsic magnitude of type Ia supernova (SNe Ia) and construct cosmological model-independent Hubble diagrams of SNe Ia. In order to test the compatibility between the reconstructed functions of $H(z)$, we perform a statistical analysis considering the latest SNe Ia sample, the so-called JLA compilation. We find that, while one of the reconstructed functions leads to a value of the local Hubble parameter $H_0$ in excellent agreement with the one reported by the Planck collaboration, the other requires a higher value of $H_0$, which is consistent with recent measurements of this quantity from Cepheids and other local distance indicators.

Li, Zhengxiang; Yu, Hongwei; Zhu, Zong-Hong; Alcaniz, J S

2015-01-01T23:59:59.000Z

130

EVIDENCE FOR TYPE Ia SUPERNOVA DIVERSITY FROM ULTRAVIOLET OBSERVATIONS WITH THE HUBBLE SPACE TELESCOPE  

E-Print Network [OSTI]

We present ultraviolet (UV) spectroscopy and photometry of four Type Ia supernovae (SNe 2004dt, 2004ef, 2005M, and 2005cf) obtained with the UV prism of the Advanced Camera for Surveys on the Hubble Space Telescope. This ...

Lewin, Walter H. G.

131

Type Ia supernova rate at a redshift of ~ 0.1  

E-Print Network [OSTI]

We present the type Ia rate measurement based on two EROS supernova search campaigns (in 1999 and 2000). Sixteen supernovae identified as type Ia were discovered. The measurement of the detection efficiency, using a Monte Carlo simulation, provides the type Ia supernova explosion rate at a redshift ~ 0.13. The result is $0.125^{+0.044+0.028}_{-0.034-0.028} h_{70}^2$ SNu where 1 SNu = 1 SN / $10^{10} L_{sun}^B$ / century. This value is compatible with the previous EROS measurement (Hardin et al. 2000), done with a much smaller sample, at a similar redshift. Comparison with other values at different redshifts suggests an evolution of the type Ia supernova rate.

Blanc, G; Alard, C; Albert, J N; Aldering, G; Amadon, A; Andersen, J; Ansari, R; Aubourg, E; Balland, C; Bareyre, P; Beaulieu, J P; Charlot, X; Conley, A; Coutures, C; Dahlen, T; Derue, F; Fan, X; Ferlet, R; Folatelli, G; Fouqué, P; Garavini, G; Glicenstein, J F; Goldman, B; Goobar, A; Gould, A; Graff, D; Gros, M; Haïssinski, J; Hamadache, C; Hardin, D; Hook, I M; De Kat, J; Kent, S; Kim, A; Lasserre, T; Le Guillou, Laurent; Lesquoy, E; Loup, C; Magneville, C; Marquette, J B; Maurice, E; Maury, A; Milsztajn, A; Moniez, M; Mouchet, M; Newberg, H; Nobili, S; Palanque-Delabrouille, Nathalie; Perdereau, O; Prévôt, L; Rahal, Y R; Regnault, N; Rich, J; Ruiz-Lapuente, P; Spiro, M; Tisserand, P; Vidal-Madjar, A; Vigroux, L; Walton, N A; Zylberajch, S

2004-01-01T23:59:59.000Z

132

Type Ia supernova rate at a redshift of ~ 0.1  

E-Print Network [OSTI]

We present the type Ia rate measurement based on two EROS supernova search campaigns (in 1999 and 2000). Sixteen supernovae identified as type Ia were discovered. The measurement of the detection efficiency, using a Monte Carlo simulation, provides the type Ia supernova explosion rate at a redshift ~ 0.13. The result is $0.125^{+0.044+0.028}_{-0.034-0.028} h_{70}^2$ SNu where 1 SNu = 1 SN / $10^{10} L_{sun}^B$ / century. This value is compatible with the previous EROS measurement (Hardin et al. 2000), done with a much smaller sample, at a similar redshift. Comparison with other values at different redshifts suggests an evolution of the type Ia supernova rate.

G. Blanc; C. Afonso; C. Alard; J. N. Albert; G. Aldering; A. Amadon; J. Andersen; R. Ansari; E. Aubourg; C. Balland; P. Bareyre; J. P. Beaulieu; X. Charlot; A. Conley; C. Coutures; T. Dahlen; F. Derue; X. Fan; R. Ferlet; G. Folatelli; P. Fouque; G. Garavini; J. F. Glicenstein; B. Goldman; A. Goobar; A. Gould; D. Graff; M. Gros; J. Haissinski; C. Hamadache; D. Hardin; I. M. Hook; J. deKat; S. Kent; A. Kim; T. Lasserre; L. LeGuillou; E. Lesquoy; C. Loup; C. Magneville; J. B. Marquette; E. Maurice; A. Maury; A. Milsztajn; M. Moniez; M. Mouchet; H. Newberg; S. Nobili; N. Palanque-Delabrouille; O. Perdereau; L. Prevot; Y. R. Rahal; N. Regnault; J. Rich; P. Ruiz-Lapuente; M. Spiro; P. Tisserand; A. Vidal-Madjar; L. Vigroux; N. A. Walton; S. Zylberajch

2004-05-11T23:59:59.000Z

133

Hipparcos calibration of the peak brightness of four SNe Ia and the value of Ho  

E-Print Network [OSTI]

Hipparcos geometrical parallaxes allowed us to calibrate the Cepheid Period-Luminosity relation and to compute the true distance moduli of 17 galaxies. Among these 17 galaxies, we selected those which generated type Ia Supernovae (SNe Ia). We found NGC 5253, parent galaxy of 1895B and 1972E, IC 4182 and NGC 4536 parents of 1937C and 1981B, respectively. We used the available B-band photometry to determine the peak brightness of these four SNe Ia. We obtained = -19.65 \\pm 0.09. Then, we built a sample of 57 SNe Ia in order to plot the Hubble diagram and determine its zero-point. Our result (ZP_{B} = -3.16 \\pm 0.10) is in agreement with other determinations and allows us to derive the following Hubble constant : Ho = 50 \\pm 3 (internal) km.s^-1.Mpc^-1.

P. Lanoix

1997-12-10T23:59:59.000Z

134

Structural studies of allosteric regulation in the class Ia Ribonucleotide reductase from Escherichia coli  

E-Print Network [OSTI]

Ribonucleotide reductase (RNR) converts ribonucleotides to deoxyribonucleotides, the building blocks for DNA replication and repair. The E. coli class Ia enzyme requires two subunits to catalyze the radical-based reduction ...

Zimanyi, Christina Marie

2013-01-01T23:59:59.000Z

135

~ VII -ATTiVIT EDILIZIE .. Servizio di Ateneo per lEnergIa  

E-Print Network [OSTI]

~ VII - ATTiVIT� EDILIZIE n'p. .' .. Servizio di Ateneo per lEnergIa - N AlJZ43 ········ - .·:tri

Di Pillo, Gianni

136

Infrastructure Assessment Mission: USACE Infrastructure Assessment (IA) Planning and Response Teams (PRTs) have two main  

E-Print Network [OSTI]

, and structural engineering applications; urban search & rescue (US&R) support; and water/wastewater) include pre- and post-declaration support for deploying an IA management cell, water/wastewater assessment

US Army Corps of Engineers

137

University Engagement and Outreach Committee Chair: PVC (IA), Prof. M Cardew-Hall  

E-Print Network [OSTI]

University Engagement and Outreach Committee Chair: PVC (IA), Prof. M Cardew-Hall Alternate Chair: PVC (IO), Dr. Erik Lithander Secretary: Ms. Jan O'Connor (Jan.OConnor@anu.edu.au) / Ms. Joanne Gash

Botea, Adi

138

2010-2011 Depto. Ciencia de la Computacin e IA Especialista Universitario Java Enterprise  

E-Print Network [OSTI]

© 2010-2011 Depto. Ciencia de la Computación e IA Especialista Universitario Java Enterprise Struts Sesión 4: Introducción a Struts 2 #12;© 2010-2011 Depto. Ciencia de la Computación e IA Especialista · Taglibs · Internacionalización · Validación · Conceptos nuevos en Struts 2 #12;© 2010-2011 Depto. Ciencia

Escolano, Francisco

139

Experto Universitario Java Enterprise 2012-2013 Depto. Ciencia de la Computacin e IA  

E-Print Network [OSTI]

Experto Universitario Java Enterprise © 2012-2013 Depto. Ciencia de la Computación e IA Lenguaje Java Avanzado Sesión 3: Tratamiento de errores #12;Lenguaje Java Avanzado © 2012-2013 Depto. Ciencia de · Tipos genéricos #12;Lenguaje Java Avanzado © 2012-2013 Depto. Ciencia de la Computación e IA Errores - 3

Escolano, Francisco

140

Gamma-rays from Type Ia supernova SN2014J  

E-Print Network [OSTI]

The whole set of INTEGRAL observations of type Ia supernova SN2014J, covering the period 16-162 days after the explosion has being analyzed. For spectral fitting the data are split into early and late periods covering days 16-35 and 50-162, respectively, optimized for Ni-56 and Co-56 lines. As expected for the early period much of the gamma-ray signal is confined to energies below $\\sim$200 keV, while for the late period it is most strong above 400 keV. In particular, in the late period Co-56 lines at 847 and 1248 keV are detected at 4.7 and 4.3 sigma respectively. The lightcurves in several representative energy bands are calculated for the entire period. The resulting spectra and lightcurves are compared with a subset of models. We confirm our previous finding that the gamma-ray data are broadly consistent with the expectations for canonical 1D models, such as delayed detonation or deflagration models for a near-Chandrasekhar mass WD. Late optical spectra (day 136 after the explosion) show rather symmetric ...

Churazov, E; Isern, J; Bikmaev, I; Bravo, E; Chugai, N; Grebenev, S; Jean, P; Knödlseder, J; Lebrun, F; Kuulkers, E

2015-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "ia mo ar" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Mo Supply Chain for Nuclear Medicine Ladimer S. Nagurney  

E-Print Network [OSTI]

November 13, 2012 #12;Nuclear Medicine: Meeting Patient Needs with 99 Mo Ladimer S. Nagurney The 99 Mo of Physics Chemistry Biology Operations Research with some Biomedical Engineering thrown in at each step;Challenges Reactors are old nearing their end of life. Planned and unplanned shutdowns have created spot

Nagurney, Anna

142

CIMAT, VIII Escuela de verano, 30 de julio -12 de agos* Introducci'on a la Geometr'ia de la Mec'anic*  

E-Print Network [OSTI]

* *fluencia de una fuerza F(x) se define su energ'ia (como funci'on de su posici'on y velocidad) por E = T +* * V donde la energ'ia cin'etica T = m(x`)2=2 y la energ'ia potencial V (x) es una funci'on que(x) entonces su energ* *'ia E se mantiene constante en el tiempo (la Ley de Conservaci'on de Energ'ia

Bor, Gil

143

Tycho Brahe's 1572 supernova as a standard type Ia explosion revealed from its light echo spectrum  

E-Print Network [OSTI]

Type Ia supernovae (SNe Ia) are thermonuclear explosions of white dwarf stars in close binary systems. They play an important role as cosmological distance indicators and have led to the discovery of the accelerated expansion of the Universe. Among the most important unsolved questions are how the explosion actually proceeds and whether accretion occurs from a companion or via the merging of two white dwarfs. Tycho Brahe's supernova of 1572 (SN 1572) is thought to be one of the best candidates for a SN Ia in the Milky Way. The proximity of the SN 1572 remnant has allowed detailed studies, such as the possible identification of the binary companion, and provides a unique opportunity to test theories of the explosion mechanism and the nature of the progenitor. The determination of the yet unknown exact spectroscopic type of SN 1572 is crucial to relate these results to the diverse population of SNe Ia. Here we report an optical spectrum of Tycho Brahe's supernova near maximum brightness, obtained from a scattered-light echo more than four centuries after the direct light of the explosion swept past Earth. We find that SN 1572 belongs to the majority class of normal SNe Ia. The presence of a strong Ca II IR feature at velocities exceeding 20,000 km/s, which is similar to the previously observed polarized features in other SNe Ia, suggests asphericity in SN 1572.

Oliver Krause; Masaomi Tanaka; Tomonori Usuda; Takashi Hattori; Miwa Goto; Stephan Birkmann; Ken'ichi Nomoto

2008-10-28T23:59:59.000Z

144

THE DISCOVERY OF THE MOST DISTANT KNOWN TYPE Ia SUPERNOVA AT REDSHIFT 1.914  

SciTech Connect (OSTI)

We present the discovery of a Type Ia supernova (SN) at redshift z = 1.914 from the CANDELS multi-cycle treasury program on the Hubble Space Telescope (HST). This SN was discovered in the infrared using the Wide-Field Camera 3, and it is the highest-redshift Type Ia SN yet observed. We classify this object as a SN Ia by comparing its light curve and spectrum with those of a large sample of Type Ia and core-collapse SNe. Its apparent magnitude is consistent with that expected from the {Lambda}CDM concordance cosmology. We discuss the use of spectral evidence for classification of z > 1.5 SNe Ia using HST grism simulations, finding that spectral data alone can frequently rule out SNe II, but distinguishing between SNe Ia and SNe Ib/c can require prohibitively long exposures. In such cases, a quantitative analysis of the light curve may be necessary for classification. Our photometric and spectroscopic classification methods can aid the determination of SN rates and cosmological parameters from the full high-redshift CANDELS SN sample.

Jones, David O.; Rodney, Steven A.; Riess, Adam G. [Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218 (United States); Mobasher, Bahram [Department of Physics and Astronomy, University of California, Riverside, CA 92521 (United States); Dahlen, Tomas; Casertano, Stefano; Koekemoer, Anton [Space Telescope Science Institute, Baltimore, MD 21218 (United States); McCully, Curtis; Keeton, Charles R.; Patel, Brandon [Department of Physics and Astronomy, Rutgers, State University of New Jersey, Piscataway, NJ 08854 (United States); Frederiksen, Teddy F.; Hjorth, Jens [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen (Denmark); Strolger, Louis-Gregory [Department of Physics, Western Kentucky University, Bowling Green, KY 42101 (United States); Wiklind, Tommy G. [Joint ALMA Observatory, ESO, Santiago (Chile); Challis, Peter [Harvard/Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States); Graur, Or [School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 69978 (Israel); Hayden, Brian; Garnavich, Peter [Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States); Weiner, Benjamin J. [Department of Astronomy, University of Arizona, Tucson, AZ 85721 (United States); Filippenko, Alexei V. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); and others

2013-05-10T23:59:59.000Z

145

FIANTD200725 arXiv:0712.3526v2  

E-Print Network [OSTI]

########### FIAN­TD­2007­25 arXiv:0712.3526v2 [hep­th] 26 Jan 2012 FIAN­TD­2007­25 arXiv: 0712.3526

146

Neutrino scattering off the stable even-even Mo isotopes  

SciTech Connect (OSTI)

Inelastic neutrino-nucleus reaction cross sections are studied focusing on the neutral current processes. Particularly, we investigate the angular and initial neutrino-energy dependence of the differential and integrated cross sections for low and intermediate energies of the incoming neutrino. The nuclear wave functions for the initial and final nuclear states are constructed in the context of the quasi-particle random phase approximation (QRPA) tested on the reproducibility of the low-lying energy spectrum. The results presented here refer to the isotopes Mo{sup 92}, Mo{sup 94}, Mo{sup 96}, Mo{sup 98} and Mo{sup 100}. These isotopes could play a significant role in supernova neutrino detection in addition to their use in double-beta and neutrinoless double-beta decay experiments (e.g. MOON, NEMO III)

Balasi, K. G.; Kosmas, T. S.; Divari, P. C. [Theoretical Physics Section, University of Ioannina, GR 45110 Ioannina (Greece)

2009-11-09T23:59:59.000Z

147

Old Sol's new use Fourteen solar ar-  

E-Print Network [OSTI]

Inside &ONLINE Old Sol's new use Fourteen solar ar- rays grace the rooftops of two HRES buildings therebelgroupInterahamwefoundheron the road in a remote region in the eastern Democratic Republic of the Congo- ductingfocusgroupinterviewswithmem- bers of the community. Looking horrorin theface HHI researchers don't flinch in examination

148

40Ar/39Ar Dating of the Bandelier Tuff and San Diego Canyon Ignimbrite...  

Open Energy Info (EERE)

(LBT) resulted in formation of the Toledo Caldera. These events were previously dated by K-Ar at 1.12 &plusmin; 0.03 Ma and 1.45 &plusmin; 0.06 Ma, respectively. Pre-Bandelier...

149

Verifying the Cosmological Utility of Type Ia Supernovae: Implications of a Dispersion in the Ultraviolet Spectra  

SciTech Connect (OSTI)

We analyze the mean rest-frame ultraviolet (UV) spectrum of Type Ia Supernovae (SNe) and its dispersion using high signal-to-noise ratio Keck-I/LRIS-B spectroscopy for a sample of 36 events at intermediate redshift (z=0.5) discovered by the Canada-France-Hawaii Telescope Supernova Legacy Survey (SNLS). We introduce a new method for removing host galaxy contamination in our spectra, exploiting the comprehensive photometric coverage of the SNLS SNe and their host galaxies, thereby providing the first quantitative view of the UV spectral properties of a large sample of distant SNe Ia. Although the mean SN Ia spectrum has not evolved significantly over the past 40percent of cosmic history, precise evolutionary constraints are limited by the absence of a comparable sample of high-quality local spectra. The mean UV spectrum of our z~;;=0.5 SNe Ia and its dispersion is tabulated for use in future applications. Within the high-redshift sample, we discover significant UV spectral variations and exclude dust extinction as the primary cause by examining trends with the optical SN color. Although progenitor metallicity may drive some of these trends, the variations we see are much larger than predicted in recent models and do not follow expected patterns. An interesting new result is a variation seen in the wavelength of selected UV features with phase. We also demonstrate systematic differences in the SN Ia spectral features with SN light curve width in both the UV and the optical. We show that these intrinsic variations could represent a statistical limitation in the future use of high-redshift SNe Ia for precision cosmology. We conclude that further detailed studies are needed, both locally and at moderate redshift where the rest-frame UV can be studied precisely, in order that future missions can confidently be planned to fully exploit SNe Ia as cosmological probes.

Nugent, Peter E; Ellis, R.S.; Sullivan, M.; Nugent, P.E.; Howell, D.A.; Gal-Yam, A.; Astier, P.; Balam, D.; Balland, C.; Basa, S.; Carlberg, R.; Conley, A.; Fouchez, D.; Guy, J.; Hardin, D.; Hook, I.; Pain, R.; Perrett, K.; Pritchet, C.J.; Regnault, N.

2008-02-28T23:59:59.000Z

150

Utilizing Type Ia Supernovae in a Large, Fast, Imaging Survey to Constrain Dark Energy  

E-Print Network [OSTI]

We study the utility of a large sample of type Ia supernovae that might be observed in an imaging survey that rapidly scans a large fraction of the sky for constraining dark energy. We consider information from the traditional luminosity distance test as well as the spread in SNeIa fluxes at fixed redshift induced by gravitational lensing. We include a treatment of photometric redshift uncertainties in our analysis. Our primary result is that the information contained in the mean distance moduli of SNeIa and the dispersion among SNeIa distance moduli complement each other, breaking a degeneracy between the present dark energy equation of state and its time variation without the need for a high-redshift supernova sample. To address photometric redshift uncertainties, we present dark energy constraints as a function of the size of an external set of spectroscopically-observed SNeIa that may be used for redshift calibration, nspec. We find that an imaging survey can constrain the dark energy equation of state at the epoch where it is best constrained with a 1-sigma error of sigma(wpiv)~0.03-0.09$, depending upon various assumptions. In addition, the marginal improvement in the error sigma(wpiv) from an increase in the spectroscopic calibration sample drops once nspec ~ 10^3. This result is important because it is of the order of the size of calibration samples likely to be compiled in the coming decade and because, for samples of this size, the spectroscopic and imaging surveys individually place comparable constraints on the dark energy equation of state. In all cases, it is best to calibrate photometric redshifts with a set of spectroscopically-observed SNeIa with relatively more objects at high redshift than the parent sample of imaging SNeIa.

Andrew R. Zentner; Suman Bhattacharya

2008-12-01T23:59:59.000Z

151

A novel three dimensional semimetallic MoS{sub 2}  

SciTech Connect (OSTI)

Transition metal dichalcogenides (TMDs) have many potential applications, while the performances of TMDs are generally limited by the less surface active sites and the poor electron transport efficiency. Here, a novel three-dimensional (3D) structure of molybdenum disulfide (MoS{sub 2}) with larger surface area was proposed based on first-principle calculations. 3D layered MoS{sub 2} structure contains the basal surface and joint zone between the different nanoribbons, which is thermodynamically stable at room temperature, as confirmed by first principles molecular dynamics calculations. Compared the two-dimensional layered structures, the 3D MoS{sub 2} not only owns the large surface areas but also can effectively avoid the aggregation. Interestingly, although the basal surface remains the property of the intrinsic semiconductor as the bulk MoS{sub 2}, the joint zone of 3D MoS{sub 2} exhibits semimetallic, which is derived from degenerate 3d orbitals of the Mo atoms. The high stability, large surface area, and high conductivity make 3D MoS{sub 2} have great potentials as high performance catalyst.

Tang, Zhen-Kun [Beijing Computational Science Research Center, Beijing 100084 (China); Departments of Physics and Electronics, Hengyang Normal University, Hengyang 421008 (China); Zhang, Hui; Liu, Li-Min, E-mail: limin.liu@csrc.ac.cn [Beijing Computational Science Research Center, Beijing 100084 (China); Liu, Hao [Chengdu Green Energy and Green Manufacturing Technology R and D Center, Chengdu, Sichuan 610207 (China); Lau, Woon-Ming [Beijing Computational Science Research Center, Beijing 100084 (China); Chengdu Green Energy and Green Manufacturing Technology R and D Center, Chengdu, Sichuan 610207 (China)

2014-05-28T23:59:59.000Z

152

A New Determination of the High Redshift Type Ia Supernova Rates with the Hubble Space Telescope Advanced Camera for Surveys  

E-Print Network [OSTI]

Schmidt, B. P. , 2003, in Supernovae and Gamma Ray Bursts,for identifying Type Ia supernovae (although spectroscopicfor future high-statistics supernovae searches in which

2008-01-01T23:59:59.000Z

153

The type Ia supernova SNLS-03D3bb from a super-Chandrasekhar-mass white dwarf star  

E-Print Network [OSTI]

magnitudes of Type IA supernovae. Astrophys. J. Lett. 413,from 42 High-Redshift Supernovae. Astrophys. J. 517, 565–Observational Evidence from Supernovae for an Accelerating

2008-01-01T23:59:59.000Z

154

COMPARING THE LIGHT CURVES OF SIMULATED TYPE Ia SUPERNOVAE WITH OBSERVATIONS USING DATA-DRIVEN MODELS  

SciTech Connect (OSTI)

We propose a robust, quantitative method to compare the synthetic light curves of a Type Ia supernova (SN Ia) explosion model with a large set of observed SNe Ia, and derive a figure of merit for the explosion model's agreement with observations. The synthetic light curves are fit with the data-driven model SALT2 which returns values for stretch, color, and magnitude at peak brightness, as well as a goodness-of-fit parameter. Each fit is performed multiple times with different choices of filter bands and epoch range in order to quantify the systematic uncertainty on the fitted parameters. We use a parametric population model for the distribution of observed SN Ia parameters from large surveys, and extend it to represent red, dim, and bright outliers found in a low-redshift SN Ia data set. We discuss the potential uncertainties of this population model and find it to be reliable given the current uncertainties on cosmological parameters. Using our population model, we assign each set of fitted parameters a likelihood of being observed in nature, and a figure of merit based on this likelihood. We define a second figure of merit based on the quality of the light curve fit, and combine the two measures into an overall figure of merit for each explosion model. We compute figures of merit for a variety of one-, two-, and three-dimensional explosion models and show that our evaluation method allows meaningful inferences across a wide range of light curve quality and fitted parameters.

Diemer, Benedikt; Kessler, Richard; Graziani, Carlo; Jordan, George C. IV; Lamb, Donald Q.; Long, Min; Van Rossum, Daniel R., E-mail: bdiemer@oddjob.uchicago.edu [Flash Center for Computational Science, University of Chicago, Chicago, IL 60637 (United States)

2013-08-20T23:59:59.000Z

155

Strong near-infrared carbon in the Type Ia supernova iPTF13ebh  

E-Print Network [OSTI]

We present near-infrared (NIR) time-series spectroscopy, as well as complementary ultraviolet (UV), optical, and NIR data, of the Type Ia supernova (SN Ia) iPTF13ebh, which was discovered within two days from the estimated time of explosion. The first NIR spectrum was taken merely 2.3 days after explosion and may be the earliest NIR spectrum yet obtained of a SN Ia. The most striking features in the spectrum are several NIR C I lines, and the C I {\\lambda}1.0693 {\\mu}m line is the strongest ever observed in a SN Ia. Interestingly, no strong optical C II counterparts were found, even though the optical spectroscopic time series began early and is densely-cadenced. Except at the very early epochs, within a few days from the time of explosion, we show that the strong NIR C I compared to the weaker optical C II appears to be general in SNe Ia. iPTF13ebh is a fast decliner with {\\Delta}m15(B) = 1.79 $\\pm$ 0.01, and its absolute magnitude obeys the linear part of the width-luminosity relation. It is therefore categ...

Hsiao, E Y; Contreras, C; Höflich, P; Sand, D; Marion, G H; Phillips, M M; Stritzinger, M; González-Gaitán, S; Mason, R E; Folatelli, G; Parent, E; Gall, C; Amanullah, R; Anupama, G C; Arcavi, I; Banerjee, D P K; Beletsky, Y; Blanc, G A; Bloom, J S; Brown, P J; Campillay, A; Cao, Y; De Cia, A; Diamond, T; Freedman, W L; Gonzalez, C; Goobar, A; Holmbo, S; Howell, D A; Johansson, J; Kasliwal, M M; Kirshner, R P; Krisciunas, K; Kulkarni, S R; Maguire, K; Milne, P A; Morrell, N; Nugent, P E; Ofek, E O; Osip, D; Palunas, P; Perley, D A; Persson, S E; Piro, A L; Rabus, M; Roth, M; Schiefelbein, J M; Srivastav, S; Sullivan, M; Suntzeff, N B; Surace, J; Wo?nia, P R; Yaron, O

2015-01-01T23:59:59.000Z

156

Effect of Mo Dispersion Size and Water Vapor on Oxidation of Two-Phase Directionally Solidified NiAl-9Mo In-Situ Composites  

SciTech Connect (OSTI)

Oxidation of two-phase NiAl-9Mo eutectics with 3 different growth rates/2nd phase Mo dispersion sizes were investigated at 900 C in air and air with 10% water vapor. Good oxidation resistance via alumina formation was observed in dry air, with Mo volatilization loss minimized by fine submicron Mo dispersions. However, extensive Mo volatilization and in-place internal oxidation of prior Mo phase regions was observed in wet air oxidation. Ramifications of this phenomenon for the development of multi-phase high-temperature alloys are discussed

Brady, Michael P [ORNL] [ORNL; Bei, Hongbin [ORNL] [ORNL; Meisner, Roberta Ann [ORNL] [ORNL; Lance, Michael J [ORNL] [ORNL; Tortorelli, Peter F [ORNL] [ORNL

2014-01-01T23:59:59.000Z

157

Ethanol Conversion on Cyclic (MO3)3 (M = Mo, W) Clusters  

SciTech Connect (OSTI)

Oxides of molybdenum and tungsten are an important class of catalytic materials with applications ranging from isomerization of alkanes and alkenes, partial oxidation of alcohols, selective reduction of nitric oxide and metathesis of alkeness.[1-10] While many studies have focused on the structure - function relationships, the nature of high catalytic activity is still being extensively investigated. There is a general agreement that the activity of supported MOx (M = W, Mo) catalysts is correlated with the presence of acidic sites, where the catalytic activity is strongly affected by the type of oxide support, delocalization of electron density, structures of tungsten oxide domains and presence of protons

Li, Zhenjun; Fang, Zongtang; Kelley, Matthew S.; Kay, Bruce D.; Rousseau, Roger J.; Dohnalek, Zdenek; Dixon, David A.

2014-03-06T23:59:59.000Z

158

Co-Mo Electric Cooperative- Residential Energy Efficiency Rebate Program  

Broader source: Energy.gov [DOE]

Co-Mo Electric Cooperative provides rebates to residential and commercial members who install air source, dual fuel, and/or geothermal heat pumps, and certain energy efficient appliances. The...

159

Q value of the 100Mo Double-Beta Decay  

E-Print Network [OSTI]

Penning trap measurements using mixed beams of 100Mo - 100Ru and 76Ge - 76Se have been utilized to determine the double-beta decay Q-values of 100Mo and 76Ge with uncertainties less than 200 eV. The value for 76Ge, 2039.04(16) keV is in agreement with the published SMILETRAP value. The new value for 100Mo, 3034.40(17) keV is 30 times more precise than the previous literature value, sufficient for the ongoing neutrinoless double-beta decay searches in 100Mo. Moreover, the precise Q-value is used to calculate the phase-space integrals and the experimental nuclear matrix element of double-beta decay.

S. Rahaman; V. -V. Elomaa; T. Eronen; J. Hakala; A. Jokinen; J. Julin; A. Kankainen; A. Saastamoinen; J. Suhonen; C. Weber; J. Äystö

2007-12-20T23:59:59.000Z

160

9 Cr-- 1 Mo steel material for high temperature application  

DOE Patents [OSTI]

One or more embodiments relates to a high-temperature, titanium alloyed, 9 Cr-1 Mo steel exhibiting improved creep strength and oxidation resistance at service temperatures up to 650.degree. C. The 9 Cr-1 Mo steel has a tempered martensite microstructure and is comprised of both large (0.5-3 .mu.m) primary titanium carbides and small (5-50 nm) secondary titanium carbides in a ratio of. from about 1:1.5 to about 1.5:1. The 9 Cr-1 Mo steel may be fabricated using exemplary austenizing, rapid cooling, and tempering steps without subsequent hot working requirements. The 9 Cr-1 Mo steel exhibits improvements in total mass gain, yield strength, and time-to-rupture over ASTM P91 and ASTM P92 at the temperature and time conditions examined.

Jablonski, Paul D; Alman, David; Dogan, Omer; Holcomb, Gordon; Cowen, Christopher

2012-11-27T23:59:59.000Z

Note: This page contains sample records for the topic "ia mo ar" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

SALT2: using distant supernovae to improve the use of Type Ia supernovae as distance indicators  

E-Print Network [OSTI]

We present an empirical model of Type Ia supernovae spectro-photometric evolution with time. The model is built using a large data set including light-curves and spectra of both nearby and distant supernovae, the latter being observed by the SNLS collaboration. We derive the average spectral sequence of Type Ia supernovae and their main variability components including a color variation law. The model allows us to measure distance moduli in the spectral range 2500-8000 A with calculable uncertainties, including those arising from variability of spectral features. Thanks to the use of high-redshift SNe to model the rest-frame UV spectral energy distribution, we are able to derive improved distance estimates for SNe Ia in the redshift range 0.8supernovae.

J. Guy; P. Astier; S. Baumont; D. Hardin; R. Pain; N. Regnault; S. Basa; R. G. Carlberg; A. Conley; S. Fabbro; D. Fouchez; I. M. Hook; D. A. Howell; K. Perrett; C. J. Pritchet; J. Rich; M. Sullivan; P. Antilogus; E. Aubourg; G. Bazin; J. Bronder; M. Filiol; N. Palanque-Delabrouille; P. Ripoche; V. Ruhlmann-Kleider

2007-01-29T23:59:59.000Z

162

[O I] ??6300, 6364 IN THE NEBULAR SPECTRUM OF A SUBLUMINOUS TYPE Ia SUPERNOVA  

SciTech Connect (OSTI)

In this Letter, a late-phase spectrum of SN 2010lp, a subluminous Type Ia supernova (SN Ia), is presented and analyzed. As in 1991bg-like SNe Ia at comparable epochs, the spectrum is characterized by relatively broad [Fe II] and [Ca II] emission lines. However, instead of narrow [Fe III] and [Co III] lines that dominate the emission from the innermost regions of 1991bg-like supernovae (SNe), SN 2010lp shows [O I] ??6300, 6364 emission, usually associated with core-collapse SNe and never previously observed in a subluminous thermonuclear explosion. The [O I] feature has a complex profile with two strong, narrow emission peaks. This suggests that oxygen is distributed in a non-spherical region close to the center of the ejecta, severely challenging most thermonuclear explosion models discussed in the literature. We conclude that, given these constraints, violent mergers are presently the most promising scenario to explain SN 2010lp.

Taubenberger, S.; Kromer, M.; Hillebrandt, W. [Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, D-85741 Garching (Germany)] [Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, D-85741 Garching (Germany); Pakmor, R. [Heidelberger Institut für Theoretische Studien, Schloss-Wolfsbrunnenweg 35, D-69118 Heidelberg (Germany)] [Heidelberger Institut für Theoretische Studien, Schloss-Wolfsbrunnenweg 35, D-69118 Heidelberg (Germany); Pignata, G. [Departamento de Ciencias Fisicas, Universidad Andres Bello, Avda. Republica 252, Santiago (Chile)] [Departamento de Ciencias Fisicas, Universidad Andres Bello, Avda. Republica 252, Santiago (Chile); Maeda, K. [Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8583 (Japan)] [Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8583 (Japan); Hachinger, S. [Julius-Maximilians-Universität Würzburg, Emil-Fischer-Str. 31, D-97074 Würzburg (Germany)] [Julius-Maximilians-Universität Würzburg, Emil-Fischer-Str. 31, D-97074 Würzburg (Germany); Leibundgut, B. [European Southern Observatory, Karl-Schwarzschild-Str. 2, D-85748 Garching (Germany)] [European Southern Observatory, Karl-Schwarzschild-Str. 2, D-85748 Garching (Germany)

2013-10-01T23:59:59.000Z

163

THE LATE-TIME REBRIGHTENING OF TYPE Ia SN 2005gj IN THE MID-INFRARED  

SciTech Connect (OSTI)

A growing number of observations reveal a subset of Type Ia supernovae undergoing circumstellar interaction (SNe Ia-CSM). We present unpublished archival Spitzer Space Telescope data on SNe Ia-CSM 2002ic and 2005gj obtained >1300 and 500 days post-discovery, respectively. Both SNe show evidence for late-time mid-infrared (mid-IR) emission from warm dust. The dust parameters are most consistent with a preexisting dust shell that lies beyond the forward-shock radius, most likely radiatively heated by optical and X-ray emission continuously generated by late-time CSM interaction. In the case of SN 2005gj, the mid-IR luminosity more than doubles after 1 yr post-discovery. While we are not aware of any late-time optical-wavelength observations at these epochs, we attribute this rebrightening to renewed shock interaction with a dense circumstellar shell.

Fox, Ori D.; Filippenko, Alexei V., E-mail: ofox@berkeley.edu [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States)

2013-07-20T23:59:59.000Z

164

Spectral Modeling of SNe Ia Near Maximum Light: Probing the Characteristics of Hydro Models  

E-Print Network [OSTI]

We have performed detailed NLTE spectral synthesis modeling of 2 types of 1-D hydro models: the very highly parameterized deflagration model W7, and two delayed detonation models. We find that overall both models do about equally well at fitting well observed SNe Ia near to maximum light. However, the Si II 6150 feature of W7 is systematically too fast, whereas for the delayed detonation models it is also somewhat too fast, but significantly better than that of W7. We find that a parameterized mixed model does the best job of reproducing the Si II 6150 line near maximum light and we study the differences in the models that lead to better fits to normal SNe Ia. We discuss what is required of a hydro model to fit the spectra of observed SNe Ia near maximum light.

E. Baron; S. Bongard; David Branch; Peter H. Hauschildt

2006-03-03T23:59:59.000Z

165

CfA4: LIGHT CURVES FOR 94 TYPE Ia SUPERNOVAE  

SciTech Connect (OSTI)

We present multi-band optical photometry of 94 spectroscopically confirmed Type Ia supernovae (SNe Ia) in the redshift range 0.0055-0.073, obtained between 2006 and 2011. There are a total of 5522 light-curve points. We show that our natural-system SN photometry has a precision of {approx}< 0.03 mag in BVr'i', {approx}< 0.06 mag in u', and {approx}< 0.07 mag in U for points brighter than 17.5 mag and estimate that it has a systematic uncertainty of 0.014, 0.010, 0.012, 0.014, 0.046, and 0.073 mag in BVr'i'u'U, respectively. Comparisons of our standard-system photometry with published SN Ia light curves and comparison stars reveal mean agreement across samples in the range of {approx}0.00-0.03 mag. We discuss the recent measurements of our telescope-plus-detector throughput by direct monochromatic illumination by Cramer et al. This technique measures the whole optical path through the telescope, auxiliary optics, filters, and detector under the same conditions used to make SN measurements. Extremely well characterized natural-system passbands (both in wavelength and over time) are crucial for the next generation of SN Ia photometry to reach the 0.01 mag accuracy level. The current sample of low-z SNe Ia is now sufficiently large to remove most of the statistical sampling error from the dark-energy error budget. But pursuing the dark-energy systematic errors by determining highly accurate detector passbands, combining optical and near-infrared (NIR) photometry and spectra, using the nearby sample to illuminate the population properties of SNe Ia, and measuring the local departures from the Hubble flow will benefit from larger, carefully measured nearby samples.

Hicken, Malcolm; Challis, Peter; Kirshner, Robert P.; Bakos, Gaspar; Berlind, Perry; Brown, Warren R.; Caldwell, Nelson; Calkins, Mike; Falco, Emilio; Fernandez, Jose; Friedman, Andrew S.; Groner, Ted; Hartman, Joel [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States); Rest, Armin [Space Telescope Science Institute, Baltimore, MD 21218 (United States); Cramer, Claire E. [NIST (National Institute of Standards and Technology), Gaithersburg, MD 20899 (United States); Wood-Vasey, W. Michael [Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA 15260 (United States); Currie, Thayne [NASA, Goddard Space Flight Center, Greenbelt, MD 20771 (United States); De Kleer, Kathy [Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Esquerdo, Gil; Everett, Mark, E-mail: mhicken@cfa.harvard.edu [Planetary Science Institute, 1700 East Fort Lowell Road, Tucson, AZ 85719 (United States); and others

2012-06-01T23:59:59.000Z

166

1 Mo 1 Do 1 Sa 1 Di 1 Fr 1 Fr 1 Mo 1 Mi 1 Sa 1 Mo 1 Do 1 So 2 Di 2 Fr 2 So 2 Mi 2 Sa 2 Sa 2 Di 2 Do 2 So 2 Di 2 Fr 2 Mo  

E-Print Network [OSTI]

1 Mo 1 Do 1 Sa 1 Di 1 Fr 1 Fr 1 Mo 1 Mi 1 Sa 1 Mo 1 Do 1 So 2 Di 2 Fr 2 So 2 Mi 2 Sa 2 Sa 2 Di 2 Do 2 So 2 Di 2 Fr 2 Mo 3 Mi 3 Sa 3 Mo 3 Do 3 So 3 So 3 Mi 3 Fr 3 Mo 3 Mi 3 Sa 3 Di 4 Do 4 So 4 Di 4 Fr 4 Mo 4 Mo 4 Do 4 Sa 4 Di 4 Do P StAU4 So 4 Mi 5 Fr 5 Mo 5 Mi 5 Sa 5 Di 5 Di 5 Fr 5 So 5 Mi 5 Fr 5 Mo

Mayberry, Marty

167

Constraining the Lattice Fluid Dark Energy from SNe Ia, BAO and OHD  

E-Print Network [OSTI]

Sanchez and Lacombe have ever developed a lattice fluid theory based on a well-defined statistical mechanical model. Taking the lattice fluid as a candidate of dark energy, we investigate the cosmic evolution of this fluid. Using the combined observational data of Type Ia Supernova (SNe Ia), Baryon Acoustic Oscillations (BAO) and Observational Hubble Data (OHD), we find the best fit value of the parameter in the model, $A = -0.3_{-0.1}^{+0.1}$. Then the cosmological implications of the model are presented.

Duan, Xiaoxian; Gao, Changjun

2011-01-01T23:59:59.000Z

168

Constraining the Lattice Fluid Dark Energy from SNe Ia, BAO and OHD  

E-Print Network [OSTI]

Sanchez and Lacombe have ever developed a lattice fluid theory based on a well-defined statistical mechanical model. Taking the lattice fluid as a candidate of dark energy, we investigate the cosmic evolution of this fluid. Using the combined observational data of Type Ia Supernova (SNe Ia), Baryon Acoustic Oscillations (BAO) and Observational Hubble Data (OHD), we find the best fit value of the parameter in the model, $A = -0.3_{-0.1}^{+0.1}$. Then the cosmological implications of the model are presented.

Xiaoxian Duan; Yichao Li; Changjun Gao

2011-11-15T23:59:59.000Z

169

A TYPE Ia SUPERNOVA AT REDSHIFT 1.55 IN HUBBLE SPACE TELESCOPE INFRARED OBSERVATIONS FROM CANDELS  

SciTech Connect (OSTI)

We report the discovery of a Type Ia supernova (SN Ia) at redshift z = 1.55 with the infrared detector of the Wide Field Camera 3 (WFC3-IR) on the Hubble Space Telescope (HST). This object was discovered in CANDELS imaging data of the Hubble Ultra Deep Field and followed as part of the CANDELS+CLASH Supernova project, comprising the SN search components from those two HST multi-cycle treasury programs. This is the highest redshift SN Ia with direct spectroscopic evidence for classification. It is also the first SN Ia at z > 1 found and followed in the infrared, providing a full light curve in rest-frame optical bands. The classification and redshift are securely defined from a combination of multi-band and multi-epoch photometry of the SN, ground-based spectroscopy of the host galaxy, and WFC3-IR grism spectroscopy of both the SN and host. This object is the first of a projected sample at z > 1.5 that will be discovered by the CANDELS and CLASH programs. The full CANDELS+CLASH SN Ia sample will enable unique tests for evolutionary effects that could arise due to differences in SN Ia progenitor systems as a function of redshift. This high-z sample will also allow measurement of the SN Ia rate out to z Almost-Equal-To 2, providing a complementary constraint on SN Ia progenitor models.

Rodney, Steven A.; Riess, Adam G.; Jones, David O. [Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218 (United States); Dahlen, Tomas; Ferguson, Henry C.; Casertano, Stefano; Grogin, Norman A. [Space Telescope Science Institute, Baltimore, MD 21218 (United States); Strolger, Louis-Gregory [Department of Physics, Western Kentucky University, Bowling Green, KY 42101 (United States); Hjorth, Jens; Frederiksen, Teddy F. [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen (Denmark); Weiner, Benjamin J. [Department of Astronomy, University of Arizona, Tucson, AZ 85721 (United States); Mobasher, Bahram [Department of Physics and Astronomy, University of California, Riverside, CA 92521 (United States); Challis, Peter; Kirshner, Robert P. [Harvard/Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States); Faber, S. M. [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 92064 (United States); Filippenko, Alexei V. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Garnavich, Peter; Hayden, Brian [Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States); Graur, Or [Department of Astrophysics, Tel Aviv University, 69978 Tel Aviv (Israel); Jha, Saurabh W. [Department of Physics and Astronomy, Rutgers, State University of New Jersey, Piscataway, NJ 08854 (United States); and others

2012-02-10T23:59:59.000Z

170

Multi-color light curves of type Ia supernovae on the color-magnitude diagram: A novel step toward more precise distance and extinction estimates  

E-Print Network [OSTI]

Date is earlier than for supernovae with smaller ?m 15 . SeeLight Curves of Type Ia Supernovae on the Color-Magnituderelation of Type Ia supernovae after optical maximum can

Wang, Lifan; Goldhaber, Gerson; Aldering, Greg; Perlmutter, Saul

2003-01-01T23:59:59.000Z

171

Coated U(Mo) Fuel: As-Fabricated Microstructures  

SciTech Connect (OSTI)

As part of the development of low-enriched uranium fuels, fuel plates have recently been tested in the BR-2 reactor as part of the SELENIUM experiment. These fuel plates contained fuel particles with either Si or ZrN thin film coating (up to 1 µm thickness) around the U-7Mo fuel particles. In order to best understand irradiation performance, it is important to determine the starting microstructure that can be observed in as-fabricated fuel plates. To this end, detailed microstructural characterization was performed on ZrN and Si-coated U-7Mo powder in samples taken from AA6061-clad fuel plates fabricated at 500°C. Of interest was the condition of the thin film coatings after fabrication at a relatively high temperature. Both scanning electron microscopy and transmission electron microscopy were employed. The ZrN thin film coating was observed to consist of columns comprised of very fine ZrN grains. Relatively large amounts of porosity could be found in some areas of the thin film, along with an enrichment of oxygen around each of the the ZrN columns. In the case of the pure Si thin film coating sample, a (U,Mo,Al,Si) interaction layer was observed around the U-7Mo particles. Apparently, the Si reacted with the U-7Mo and Al matrix during fuel plate fabrication at 500°C to form this layer. The microstructure of the formed layer is very similar to those that form in U-7Mo versus Al-Si alloy diffusion couples annealed at higher temperatures and as-fabricated U-7Mo dispersion fuel plates with Al-Si alloy matrix fabricated at 500°C.

Emmanuel Perez; Dennis D. Keiser, Jr.; Ann Leenaers; Sven Van den Berghe; Tom Wiencek

2014-04-01T23:59:59.000Z

172

ar diffusion coefficient: Topics by E-print Network  

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

diffusion is examined. Kazuhiko Seki; Saurabh Mogre; Shigeyuki Komura 2014-02-05 4 Fractal diffusion coefficient from dynamical zeta functions Nonlinear Sciences (arXiv)...

173

ArKion Systems | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 NoPublic Utilities Address: 160 East 300AlgoilEnergy Information theDevelopment Co. Place:Aquilla, Texas:ArKion

174

CIMAT, VIII Escuela de verano, 30 de julio -12 de ago* Introducci'on a la Geometr'ia de la Mec'ani*  

E-Print Network [OSTI]

con un valor fijo de la energ* *'ia corresponden a secciones del cono del inciso (a) por * *energ'ia tienen el mismo semi-eje mayor. 11.Demuestra la tercera ley de Kepler: toda soluci'on peri Introducci'on a la Geometr'ia de la Mec'ani* *ca Cl'asica Problemas 7 - 12

Bor, Gil

175

Revealing progenitors of type Ia supernovae from their light curves and spectra  

E-Print Network [OSTI]

In the single degenerate (SD) scenario of type Ia supernovae (SNe Ia), the collision of the ejecta with its companion results in stripping hydrogen rich matter from the companion star. This hydrogen rich matter might leave its trace in the light curves and/or spectra. In this paper, we perform radiation hydrodynamical simulations of this collision for three binary systems. As a result, we find that the emission from the shock-heated region is not as strong as in the previous study. This weak emission, however, may be a result of our underestimate of the coupling between the gas and radiation in the shock interaction. Therefore, though our results suggest that the observed early light curves of SNe Ia can not rule out binary systems with a short separation as the progenitor system, more elaborate numerical studies will be needed to reach a fair conclusion. Alternatively, our results indicate that the feature observed in the early phase of a recent type Ia SN 2014J might result from interaction of the ejecta wi...

Kutsuna, Masamichi

2015-01-01T23:59:59.000Z

176

ON THE LIRA LAW AND THE NATURE OF EXTINCTION TOWARD TYPE Ia SUPERNOVAE  

SciTech Connect (OSTI)

We have studied the relation between the color evolution of Type Ia supernovae (SNe Ia) from maximum light to the Lira law regime and the presence of narrow absorption features. Based on a nearby sample of 89 SNe Ia, we have found that the rate of change of B - V colors at late phases (between 35 and 80 days after maximum) varies significantly among different SNe Ia. At maximum light, faster Lira law B - V decliners have significantly higher equivalent widths of blended Na I D1 and D2 narrow absorption lines, redder colors, and lower R{sub V} reddening laws. We do not find faster Lira law B - V decliners to have a strong preference for younger galaxy environments, where higher interstellar material (ISM) column densities would be expected. We interpret these results as evidence for the presence of circumstellar material. The differences in colors and reddening laws found at maximum light are also present 55 days afterward, but unlike the colors at maximum they show a significant variation among different host galaxy morphological types. This suggests that the effect of ISM on the colors is more apparent at late times. Finally, we discuss how the transversal expansion of the ejecta in an inhomogeneous ISM could mimic some of these findings.

Foerster, Francisco; Gonzalez-Gaitan, Santiago [Departamento de Astronomia, Universidad de Chile, Casilla 36-D, Santiago (Chile); Folatelli, Gaston [Kavli Institute for the Physics and Mathematics of the Universe, Todai Institutes for Advanced Study (TODIAS), University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8583 (Japan); Morrell, Nidia [Las Campanas Observatory, Carnegie Observatories, Casilla 601, La Serena (Chile)

2013-07-20T23:59:59.000Z

177

METALLICITY DIFFERENCES IN TYPE Ia SUPERNOVA PROGENITORS INFERRED FROM ULTRAVIOLET SPECTRA  

SciTech Connect (OSTI)

Two ''twin'' Type Ia supernovae (SNe Ia), SNe 2011by and 2011fe, have extremely similar optical light-curve shapes, colors, and spectra, yet have different ultraviolet (UV) continua as measured in Hubble Space Telescope spectra and measurably different peak luminosities. We attribute the difference in the UV continua to significantly different progenitor metallicities. This is the first robust detection of different metallicities for SN Ia progenitors. Theoretical reasoning suggests that differences in metallicity also lead to differences in luminosity. SNe Ia with higher progenitor metallicities have lower {sup 56}Ni yields and lower luminosities for the same light-curve shape. SNe 2011by and 2011fe have different peak luminosities ({Delta}M{sub V} Almost-Equal-To 0.6 mag), which correspond to different {sup 56}Ni yields: M{sub 11fe}({sup 56}Ni) / M{sub 11by}({sup 56}Ni) = 1.7{sup +0.7}{sub -0.5}. From theoretical models that account for different neutron-to-proton ratios in progenitors, the differences in {sup 56}Ni yields for SNe 2011by and 2011fe imply that their progenitor stars were above and below solar metallicity, respectively. Although we can distinguish progenitor metallicities in a qualitative way from UV data, the quantitative interpretation in terms of abundances is limited by the present state of theoretical models.

Foley, Ryan J.; Kirshner, Robert P. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

2013-05-20T23:59:59.000Z

178

Tycho Brahe's 1572 supernova as a standard type Ia explosion revealed from its light echo spectrum  

E-Print Network [OSTI]

Type Ia supernovae (SNe Ia) are thermonuclear explosions of white dwarf stars in close binary systems. They play an important role as cosmological distance indicators and have led to the discovery of the accelerated expansion of the Universe. Among the most important unsolved questions are how the explosion actually proceeds and whether accretion occurs from a companion or via the merging of two white dwarfs. Tycho Brahe's supernova of 1572 (SN 1572) is thought to be one of the best candidates for a SN Ia in the Milky Way. The proximity of the SN 1572 remnant has allowed detailed studies, such as the possible identification of the binary companion, and provides a unique opportunity to test theories of the explosion mechanism and the nature of the progenitor. The determination of the yet unknown exact spectroscopic type of SN 1572 is crucial to relate these results to the diverse population of SNe Ia. Here we report an optical spectrum of Tycho Brahe's supernova near maximum brightness, obtained from a scatter...

Krause, Oliver; Usuda, Tomonori; Hattori, Takashi; Goto, Miwa; Birkmann, Stephan; Nomoto, Ken'ichi

2008-01-01T23:59:59.000Z

179

SEASONAL V A R IA TIONS IN STRUCTURE AND CIRCULATION IN THE RED SEA  

E-Print Network [OSTI]

SEASONAL V A R IA TIONS IN STRUCTURE AND CIRCULATION IN THE RED SEA A DISSERTATION SUBMITTE D and surface circulation in the Red Sea, occur r ing along the north-south axis of the Sea and extending fr om on in the northern Red Sea is frorn the nor th-northwest throughout the year' during the winter ( fr om October

Luther, Douglas S.

180

Seminar Ia, cetrti letnik, stari program LONGITUDINAL DYNAMICS OF PARTICLES IN ACCELERATORS  

E-Print Network [OSTI]

Seminar Ia, cetrti letnik, stari program LONGITUDINAL DYNAMICS OF PARTICLES IN ACCELERATORS Author motion of charged particles in particle accelerators. The technique of acceleration by electromagnetic waves is explored and the stability of motion under such acceleration is inspected. The seminar

Â?umer, Slobodan

Note: This page contains sample records for the topic "ia mo ar" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Section I. Summary of Project Activities Section I-A. 2008-2009 Project Summary  

E-Print Network [OSTI]

Section I. Summary of Project Activities Section I-A. 2008-2009 Project Summary University year, we accomplished the following: · Established a dual career opportunity procedure vetted to address, communicate procedures for the new daycare facility, and to explore the potential

Farritor, Shane

182

On the thermonuclear runaway in Type Ia supernovae: How to run away  

E-Print Network [OSTI]

Type Ia Supernovae are thought to be thermonuclear explosions of massive white dwarfs (WD). We present the first study of multi-dimensional effects during the final hours prior to the thermonuclear runaway which leads to the explosion. The calculations utilize an implicit, 2-D hydrodynamical code

P. Höflich; J. Stein

2002-01-01T23:59:59.000Z

183

Turbulent Oxygen Flames in Type Ia Supernovae A. J. Aspden1  

E-Print Network [OSTI]

Turbulent Oxygen Flames in Type Ia Supernovae A. J. Aspden1 , J. B. Bell1 , and S. E. Woosley2 oxygen flames. The two aims of the paper are to examine the response of the inductive oxygen flame to intense levels of turbulence, and to explore the possibility of transition to detonation in the oxygen

184

High-Velocity Features of Calcium and Silicon in the Spectra of Type Ia Supernovae  

E-Print Network [OSTI]

"High-velocity features" (HVFs) are spectral features in Type Ia supernovae (SNe Ia) that have minima indicating significantly higher (by greater than about 6000 km/s) velocities than typical "photospheric-velocity features" (PVFs). The PVFs are absorption features with minima indicating typical photospheric (i.e., bulk ejecta) velocities (usually ~9000-15,000 km/s near B-band maximum brightness). In this work we undertake the most in-depth study of HVFs ever performed. The dataset used herein consists of 445 low-resolution optical and near-infrared (NIR) spectra (at epochs up to 5 d past maximum brightness) of 210 low-redshift SNe Ia that follow the "Phillips relation." A series of Gaussian functions is fit to the data in order to characterise possible HVFs of Ca II H&K, Si II {\\lambda}6355, and the Ca II NIR triplet. The temporal evolution of the velocities and strengths of the PVFs and HVFs of these three spectral features is investigated, as are possible correlations with other SN Ia observables. We f...

Silverman, Jeffrey M; Marion, G H; Wheeler, J Craig; Barna, Barnabas; Szalai, Tamas; Mulligan, Brian; Filippenko, Alexei V

2015-01-01T23:59:59.000Z

185

The superconducting spin valve and triplet superconductivity I.A. Garifullin a,n  

E-Print Network [OSTI]

The superconducting spin valve and triplet superconductivity I.A. Garifullin a,n , P.V. Leksin s t r a c t A review of our recent results on the spin valve effect is presented. We have used coefficient DF and the exchange splitting I of the conduction band in the F layer [1]. For pure Fe the value

Fominov, Yakov

186

HIGH-VELOCITY LINE FORMING REGIONS IN THE TYPE Ia SUPERNOVA 2009ig  

SciTech Connect (OSTI)

We report measurements and analysis of high-velocity (HVF) (>20,000 km s{sup –1}) and photospheric absorption features in a series of spectra of the Type Ia supernova (SN) 2009ig obtained between –14 days and +13 days with respect to the time of maximum B-band luminosity (B-max). We identify lines of Si II, Si III, S II, Ca II, and Fe II that produce both HVF and photospheric-velocity (PVF) absorption features. SN 2009ig is unusual for the large number of lines with detectable HVF in the spectra, but the light-curve parameters correspond to a slightly overluminous but unexceptional SN Ia (M{sub B} = –19.46 mag and ?m{sub 15}(B) = 0.90 mag). Similarly, the Si II ?6355 velocity at the time of B-max is greater than 'normal' for an SN Ia, but it is not extreme (v{sub Si} = 13,400 km s{sup –1}). The –14 days and –13 days spectra clearly resolve HVF from Si II ?6355 as separate absorptions from a detached line forming region. At these very early phases, detached HVF are prevalent in all lines. From –12 days to –6 days, HVF and PVF are detected simultaneously, and the two line forming regions maintain a constant separation of about 8000 km s{sup –1}. After –6 days all absorption features are PVF. The observations of SN 2009ig provide a complete picture of the transition from HVF to PVF. Most SNe Ia show evidence for HVF from multiple lines in spectra obtained before –10 days, and we compare the spectra of SN 2009ig to observations of other SNe. We show that each of the unusual line profiles for Si II ?6355 found in early-time spectra of SNe Ia correlate to a specific phase in a common development sequence from HVF to PVF.

Marion, G. H.; Foley, Ryan J.; Challis, Peter; Kirshner, Robert P. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Vinko, Jozsef; Wheeler, J. Craig; Silverman, Jeffrey M. [University of Texas at Austin, 1 University Station C1400, Austin, TX 78712-0259 (United States); Hsiao, Eric Y. [Carnegie Observatories, Las Campanas Observatory, Colina El Pino, Casilla 601 (Chile); Brown, Peter J. [George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy, Department of Physics and Astronomy, Texas A and M University, 4242 AMU, College Station, TX 77843 (United States); Filippenko, Alexei V. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Garnavich, Peter [Department of Physics, University of Notre Dame, 225 Nieuwland Science Hall, Notre Dame, IN 46556 (United States); Landsman, Wayne B. [Adnet Systems, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Parrent, Jerod T. [Las Cumbres Observatory Global Telescope Network, Goleta, CA 93117 (United States); Pritchard, Tyler A.; Roming, Peter W. A. [Department of Astronomy and Astrophysics, Penn State University, 525 Davey Lab, University Park, PA 16802 (United States); Wang, Xiaofeng, E-mail: gmarion@cfa.harvard.edu [Physics Department and Tsinghua Center for Astrophysics (THCA), Tsinghua University, Beijing 1,00084 (China)

2013-11-01T23:59:59.000Z

187

Production of Mo-99 using low-enriched uranium silicide  

SciTech Connect (OSTI)

Over the last several years, uranium silicide fuels have been under development as low-enriched uranium (LEU) targets for Mo-99. The use of LEU silicide is aimed at replacing the UAl{sub x} alloy in the highly-enriched uranium dissolution process. A process to recover Mo-99 from low-enriched uranium silicide is being developed at Argonne National Laboratory. The uranium silicide is dissolved in alkaline hydrogen peroxide. Experiments performed to determine the optimum dissolution procedure are discussed, and the results of dissolving a portion of a high-burnup (>40%) U{sub 3}Si{sub 2} miniplate are presented. Future work related to Mo-99 separation and waste disposal are also discussed.

Hutter, J. C.; Srinivasan, B.; Vicek, M.; Vandegrift, G. F.

1994-09-01T23:59:59.000Z

188

Multiphonon resonant Raman scattering in MoS{sub 2}  

SciTech Connect (OSTI)

Optical emission spectrum of a resonantly (??=?632.8?nm) excited molybdenum disulfide (MoS{sub 2}) is studied at liquid helium temperature. More than 20 peaks in the energy range spanning up to 1400?cm{sup ?1} from the laser line, which are related to multiphonon resonant Raman scattering processes, are observed. The attribution of the observed lines involving basic lattice vibrational modes of MoS{sub 2} and both the longitudinal (LA(M)) and the transverse (TA(M) and/or ZA(M)) acoustic phonons from the vicinity of the high-symmetry M point of the MoS{sub 2} Brillouin zone is proposed.

Go?asa, K., E-mail: Katarzyna.Golasa@fuw.edu.pl; Grzeszczyk, M.; Wysmo?ek, A.; Babi?ski, A. [Faculty of Physics, University of Warsaw, ul. Ho?a 69, 00-681 Warszawa (Poland); Leszczy?ski, P.; Faugeras, C.; Nicolet, A. A. L.; Potemski, M. [Laboratoire National des Champs Magnétiques Intenses, CNRS-UJF-UPS-INSA, 25, avenue des Martyrs, 38042 Grenoble (France)

2014-03-03T23:59:59.000Z

189

Identification of phases in the interaction layer between U-Mo-Zr/Al and U-Mo-Zr/Al-Si  

SciTech Connect (OSTI)

Out-of-pile diffusion experiments were performed between U-7wt.% Mo-1wt.% Zr and Al or Al A356 (7,1wt.% Si) at 550 deg. C. In this work morphological characterization and phase identification on both interaction layer are presented. They were carried out by the use of different techniques: optical and scanning electron microscopy, X-Ray diffraction and WDS microanalysis. In the interaction layer U-7wt.% Mo-1wt.% Zr/Al, the phases UAl{sub 3}, UAl{sub 4}, Al{sub 20}Mo{sub 2}U and Al{sub 43}Mo{sub 4}U{sub 6} were identified. In the interaction layer U-7wt.% Mo-1wt.% Zr/Al A356, the phases U(Al, Si) with 25at.% Si and Si{sub 5}U{sub 3} were identified. This last phase, with a higher Si concentration, was identified with XRD Synchrotron radiation performed at the National Synchrotron Light Laboratory (LNLS), Campinas, Brasil. (author)

Varela, C.L. Komar; Arico, S.F.; Mirandou, M.; Balart, S.N. [Departamento Materiales, GIDAT, GAEN, CNEA, Avda. Gral Paz 1499, B1650KNA, San Martin (Argentina); Gribaudo, L.M. [Departamento Materiales, GIDAT, GAEN, CNEA, Avda. Gral Paz 1499, B1650KNA, San Martin (Argentina); CONICET, Avda. Rivadavia 1917, C1033AAJ, Buenos Aires (Argentina)

2008-07-15T23:59:59.000Z

190

Hydrotreatment of Athabasca bitumen derived gas oil over Ni-Mo, Ni-W, and Co-Mo catalysts  

SciTech Connect (OSTI)

The hydrotreatment of Athabasca bitumen derived heavy gas oil containing 4.08% S and 0.49% N was carried out in a trickle bed reactor over Ni-W, Ni-Mo, and Co-Mo catalysts supported on zeolite-alumina-silica at 623-698 K, LHSV of 1-4, gas flow rate 890 m[sup 3][sub H2]/m[sup 3][sub oil] (5,000 sef/bbl), and pressure of 6.89 MPa. Analyses for viscosity, density, aniline point, ASTM mid boiling point distillation, C/H ratio, and percentage of N and S in the final product were carried out to characterize the product oil. The amounts of N and S removed indicated the hydrodenitrogenation and hydrodesulfurization activity of the catalysts. Results of zeolite-alumina-silica-supported catalysts are compared to those obtained with commercially available Ni-Mo, Ni-W, and Co-Mo on [gamma]-alumina. Ni-Mo supported on zeolite-alumina-silica was most active and could remove as much as 99 % S and 89% N present in the oil at 698 K. The data for HDN and HDS fitted the pseudo first order model. The kinetic model is described in detail.

Diaz-Real, R.A.; Mann, R.S.; Sambi, I.S. (Univ. of Ottawa, Ontario (Canada). Dept. of Chemical Engineering)

1993-07-01T23:59:59.000Z

191

Published in 2009 by John Wiley & Sons, Ltd Correspondence to: David A. Laird, USDA, ARS, National Soil Tilth Laboratory, 2110 University Blvd., Ames IA 50011-3120, USA.  

E-Print Network [OSTI]

quantities of renewable bioenergy while simultaneously reducing emissions of greenhouse gases. At the present time, the pyrolysis platform is economically marginal because markets for bio-oil and biochar bioenergy industry has been promoted as a means of simultaneously improving energy secu- rity, improving

Lehmann, Johannes

192

Revised isotopic (40 Ar) age for the lamproite volcano of  

E-Print Network [OSTI]

Revised isotopic (40 Ar/39 Ar) age for the lamproite volcano of Cabezos Negros, Fortuna Basin (lamproites) of the Fortuna Basin in southeast Spain. This age is significantly older than earlier reported K. Because the volcanic rocks are intercalated in the stratigraphic sequence of the Fortuna Basin directly

Utrecht, Universiteit

193

FIES ThAr atlas orders 157 79  

E-Print Network [OSTI]

FIES ThAr atlas orders 157 ­ 79 wavelength 3620 ­ 7260 °A Dec 2007 medium resolution file: FIql020001.fits John Telting Nordic Optical Telescope, La Palma, Spain #12;This ThAr atlas was made in Dec file used is FIql020001.fits. A halogen exposure (FIql020002.fits) was used to trace the orders

194

CHEMILUMINESCENT CHEMI-IONIZATION: Ar* + Ca AND THE CaAr+ EMISSION SPECTRUM  

SciTech Connect (OSTI)

A flowing afterglow chemiluminescence apparatus has been used to analyze visible fluorescence in the Ar* ({sup 3}P{sub 2}{sup o}) + Ca ({sup 1}S{sub 0}) reaction. The rate constants for production of Ca{sup +} ({sup 2}P{sub 3/2}{sup o}) and Ca{sup +} ({sup 2}P{sub 1/2}{sup o}) were measured to be 1.6 x 10{sup -10} cm{sup 3}-molecule{sup -1} sec{sup -1} and 3.2 x 10{sup -11} cm{sup 3} molecule{sup -1} sec{sup -1}, respectively. These results demonstrate a transfer of the total electronic angular momentum polarization in Ar* tothe excited ion levels. The molecular band spectrum of the associative ionization product CaAr{sup +} (A{sup 2}{Pi}) was observed. Molecular fluorescence constituted 14% of the total fluorescence from all ion products. This spectrum was analyzed with a model (exp-Z4) potential, yielding, for the ground state, {Chi}{sup 2}{Sigma}{sup +}, R{sub e} = 2.8 {angstrom}, {omega}''{sub e} = 87 cm{sup -1}, and D''{sub e} = 1000 cm{sup -1}, and, for the A{sup 2}{Pi} state, R{sub e} = 2.6 {angstrom}, {omega}'{sub e} = 200 cm{sup -1}, and D'{sub e} = 4900 cm{sup -1}. The nascent internal state distribution in CaAr{sup +} is found to consist of a fairly narrow range of high vibrational levels. The analysis of spectra from chemiluminescent reaction is a well established technique for elucidating the product state distributions of elementary processes. In this paper, they use the analysis of the chemiluminescent chemi-ionization reactions between metastable argon atoms and calcium atoms to expose the dynamics of associative ionization (AI) and to measure the branching ratios for chemi-ionization into more than one product channel.

Hartman, Dennis C.; Winn, John S.

1980-09-01T23:59:59.000Z

195

COSMOLOGY WITH PHOTOMETRICALLY CLASSIFIED TYPE Ia SUPERNOVAE FROM THE SDSS-II SUPERNOVA SURVEY  

SciTech Connect (OSTI)

We present the cosmological analysis of 752 photometrically classified Type Ia Supernovae (SNe Ia) obtained from the full Sloan Digital Sky Survey II (SDSS-II) Supernova (SN) Survey, supplemented with host-galaxy spectroscopy from the SDSS-III Baryon Oscillation Spectroscopic Survey. Our photometric-classification method is based on the SN classification technique of Sako et al., aided by host-galaxy redshifts (0.05 < z < 0.55). SuperNova ANAlysis simulations of our methodology estimate that we have an SN Ia classification efficiency of 70.8%, with only 3.9% contamination from core-collapse (non-Ia) SNe. We demonstrate that this level of contamination has no effect on our cosmological constraints. We quantify and correct for our selection effects (e.g., Malmquist bias) using simulations. When fitting to a flat {Lambda}CDM cosmological model, we find that our photometric sample alone gives {Omega} {sub m} = 0.24{sup +0.07} {sub -0.05} (statistical errors only). If we relax the constraint on flatness, then our sample provides competitive joint statistical constraints on {Omega} {sub m} and {Omega}{sub {Lambda}}, comparable to those derived from the spectroscopically confirmed Three-year Supernova Legacy Survey (SNLS3). Using only our data, the statistics-only result favors an accelerating universe at 99.96% confidence. Assuming a constant wCDM cosmological model, and combining with H {sub 0}, cosmic microwave background, and luminous red galaxy data, we obtain w = -0.96{sup +0.10} {sub -0.10}, {Omega} {sub m} = 0.29{sup +0.02} {sub -0.02}, and {Omega} {sub k} = 0.00{sup +0.03} {sub -0.02} (statistical errors only), which is competitive with similar spectroscopically confirmed SNe Ia analyses. Overall this comparison is reassuring, considering the lower redshift leverage of the SDSS-II SN sample (z < 0.55) and the lack of spectroscopic confirmation used herein. These results demonstrate the potential of photometrically classified SN Ia samples in improving cosmological constraints.

Campbell, Heather; D'Andrea, Chris B; Nichol, Robert C.; Smith, Mathew; Lampeitl, Hubert [Institute of Cosmology and Gravitation, University of Portsmouth, Portsmouth, PO1 3FX (United Kingdom)] [Institute of Cosmology and Gravitation, University of Portsmouth, Portsmouth, PO1 3FX (United Kingdom); Sako, Masao [Department of Physics and Astronomy, University of Pennsylvania, 209 South 33rd Street, Philadelphia, PA 19104 (United States)] [Department of Physics and Astronomy, University of Pennsylvania, 209 South 33rd Street, Philadelphia, PA 19104 (United States); Olmstead, Matthew D.; Brown, Peter; Dawson, Kyle S. [Department of Physics and Astronomy, University of Utah, 115 South 1400 East 201, Salt Lake City, UT 84112 (United States)] [Department of Physics and Astronomy, University of Utah, 115 South 1400 East 201, Salt Lake City, UT 84112 (United States); Bassett, Bruce [Mathematics Department, University of Cape Town, Rondebosch, Cape Town (South Africa)] [Mathematics Department, University of Cape Town, Rondebosch, Cape Town (South Africa); Biswas, Rahul; Kuhlmann, Steve [Argonne National Laboratory, 9700 South Cass Avenue, Lemont, IL 60439 (United States)] [Argonne National Laboratory, 9700 South Cass Avenue, Lemont, IL 60439 (United States); Cinabro, David [Department of Physics and Astronomy, Wayne State University, Detroit, MI 48126 (United States)] [Department of Physics and Astronomy, Wayne State University, Detroit, MI 48126 (United States); Dilday, Ben [Las Cumbres Observatory Global Telescope Network, 6740 Cortona Dr., Suite 102, Goleta, CA 93117 (United States)] [Las Cumbres Observatory Global Telescope Network, 6740 Cortona Dr., Suite 102, Goleta, CA 93117 (United States); Foley, Ryan J. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)] [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Frieman, Joshua A. [Department of Astronomy and Astrophysics, The University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637 (United States)] [Department of Astronomy and Astrophysics, The University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Garnavich, Peter [Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States)] [Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States); Hlozek, Renee [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States)] [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Jha, Saurabh W. [Department of Physics and Astronomy, Rutgers University, 136 Frelinghuysen Road, Piscataway, NJ 08854 (United States)] [Department of Physics and Astronomy, Rutgers University, 136 Frelinghuysen Road, Piscataway, NJ 08854 (United States); Kunz, Martin, E-mail: Heather.Campbell@port.ac.uk [African Institute for Mathematical Sciences, Muizenberg, 7945, Cape Town (South Africa)] [African Institute for Mathematical Sciences, Muizenberg, 7945, Cape Town (South Africa); and others

2013-02-15T23:59:59.000Z

196

Policy Flash 2013-71 AL 2013-11 NON M&O CONTRACTOR BUSINESS SYSTEMS...  

Broader source: Energy.gov (indexed) [DOE]

1 AL 2013-11 NON M&O CONTRACTOR BUSINESS SYSTEMS CLAUSES FOR SECTION H Policy Flash 2013-71 AL 2013-11 NON M&O CONTRACTOR BUSINESS SYSTEMS CLAUSES FOR SECTION H Policy Flash - AL...

197

Nanoscale Phase Separation In Epitaxial Cr-Mo and Cr-V Alloy...  

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

Separation In Epitaxial Cr-Mo and Cr-V Alloy Thin Films Studied Using Atom Probe Tomography: Comparison Of Nanoscale Phase Separation In Epitaxial Cr-Mo and Cr-V Alloy Thin Films...

198

MO"BIUS-INVARIANT KNOT ENERGIES R.B. KUSNER  

E-Print Network [OSTI]

for divergence-free vector fields which arise in modeling incompressible fluid flow.6,7These new knot energies MO"BIUS-INVARIANT KNOT ENERGIES R.B. KUSNER, Urbana, IL, USA 61801-2975 There has been recent interest in knot energies among mathematicians

Sullivan, John M.

199

MO"BIUS-INVARIANT KNOT ENERGIES R.B. KUSNER  

E-Print Network [OSTI]

for divergence-free vector fields which arise in modeling incompressible fluid flow.? These new knot energies may MO"BIUS-INVARIANT KNOT ENERGIES R.B. KUSNER, Urbana, IL, USA 61801-2975 There has been recent interest in knot energies among mathematicians

200

Phase transitions in the adsorption system Li/Mo(112)  

E-Print Network [OSTI]

Experimental studies of the phase transitions in the adsorption system Li/Mo(112) are presented. This system is a model system for highly anisotropic interactions. From measurements of the half-widths of the low-energy electron diffraction spot...

Fedorus, A.; Kolthoff, D.; Koval, V.; Lyuksyutov, Igor F.; Naumovets, AG; Pfnur, H.

2000-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "ia mo ar" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Major Program Offices  

Energy Savers [EERE]

WY UT NM LANL 259.4 SNL 615.2 AR MS HI AZ SC SRNLS 43.1 OK KS ME WA PNNL 862.4 CA LBNL 852.2 LLNL 66.4 CO NREL 2,808.7 TX MO IL ANL 697.5 IA AMES 21.4 MN WI MI OH KY TN...

202

U.S. Energy Information Administration | Annual Energy Outlook...  

Annual Energy Outlook 2013 [U.S. Energy Information Administration (EIA)]

Supply Model Regions Atlantic WA MT WY ID NV UT CO AZ NM TX OK IA KS MO IL IN KY TN MS AL FL GA SC NC WV PA NJ MD DE NY CT ME RI MA NH VA WI MI OH NE SD MN ND AR LA OR CA VT...

203

U.S. Energy Information Administration | Annual Energy Outlook...  

Annual Energy Outlook 2013 [U.S. Energy Information Administration (EIA)]

East North Central Mountain AK WA MT WY ID NV UT CO AZ NM TX OK IA KS MO IL IN KY TN MS AL FL GA SC NC WV PA NJ MD DE NY CT VT ME RI MA NH VA WI MI OH NE SD MN ND AR LA OR CA HI...

204

Annual Energy Outlook 2012  

Annual Energy Outlook 2013 [U.S. Energy Information Administration (EIA)]

Supply Model Regions Atlantic WA MT WY ID NV UT CO AZ NM TX OK IA KS MO IL IN KY TN MS AL FL GA SC NC WV PA NJ MD DE NY CT ME RI MA NH VA WI MI OH NE SD MN ND AR LA OR CA VT...

205

Annual Energy Outlook 2012  

Gasoline and Diesel Fuel Update (EIA)

AZ OR CA HI V MT WY ID UT CO IV OK IA KS MO IL IN KY TN WI MI OH NE SD MN ND II NM TX MS AL AR LA III NJ CT VT ME RI MA NH FL GA SC NC WV MD DE VA NY PA I PAD District I - East...

206

U.S. Energy Information Administration | Annual Energy Outlook...  

Gasoline and Diesel Fuel Update (EIA)

AZ OR CA HI V MT WY ID UT CO IV OK IA KS MO IL IN KY TN WI MI OH NE SD MN ND II NM TX MS AL AR LA III NJ CT VT ME RI MA NH FL GA SC NC WV MD DE VA NY PA I PAD District I - East...

207

Restframe I-band Hubble diagram for type Ia supernovae up to redshift z ~; 0.5  

E-Print Network [OSTI]

in STScI Symposium Ser. 13, Supernovae and gamma-ray bursts:Highlight: The Physics of Supernovae, ed. W. Hillebrandt &diagram for type Ia supernovae up to redshift z ? 0.5 ? S.

2005-01-01T23:59:59.000Z

208

Mechanistic studies of proton-coupled electron transfer in aminotyrosine- and fluorotyrosine- substituted class Ia Ribonucleotide reductase  

E-Print Network [OSTI]

Ribonucleotide reductase (RNR) catalyzes the conversion of nucleotides to 2'- deoxynucleotides in all organisms. The class Ia RNR from Escherichia coli is active as an a2p2 complex and utilizes an unprecedented mechanism ...

Minnihan, Ellen Catherine

2012-01-01T23:59:59.000Z

209

Function of the Diiron Cluster of Escherichia coli Class Ia Ribonucleotide Reductase in Proton-Coupled Electron Transfer  

E-Print Network [OSTI]

The class Ia ribonucleotide reductase (RNR) from Escherichia coli employs a free-radical mechanism, which involves bidirectional translocation of a radical equivalent or “hole” over a distance of ~35 Å from the stable ...

Wörsdörfer, Bigna

210

In vivo cofactor biosynthesis and maintenance in the class Ia ribonucleotide reductase small subunit of Escherichia coli  

E-Print Network [OSTI]

The small subunit ([beta]2) of Escherichia coli class Ia ribonucleotide reductases (RNRs) contains a diferric tyrosyl radical (Y*) cofactor essential for the conversion of nucleotides to deoxynucleotides that are needed ...

Wu, Chia-Hung, Ph. D. Massachusetts Institute of Technology

2009-01-01T23:59:59.000Z

211

On the small-scale stability of thermonuclear flames in Type Ia supernovae  

E-Print Network [OSTI]

We present a numerical model which allows us to investigate thermonuclear flames in Type Ia supernova explosions. The model is based on a finite-volume explicit hydrodynamics solver employing PPM. Using the level-set technique combined with in-cell reconstruction and flux-splitting schemes we are able to describe the flame in the discontinuity approximation. We apply our implementation to flame propagation in Chandrasekhar-mass Type Ia supernova models. In particular we concentrate on intermediate scales between the flame width and the Gibson-scale, where the burning front is subject to the Landau-Darrieus instability. We are able to reproduce the theoretical prediction on the growth rates of perturbations in the linear regime and observe the stabilization of the flame in a cellular shape. The increase of the mean burning velocity due to the enlarged flame surface is measured. Results of our simulation are in agreement with semianalytical studies.

F. K. Roepke; J. C. Niemeyer; W. Hillebrandt

2003-05-02T23:59:59.000Z

212

Combined U-Th/He and 40Ar/39Ar geochronology of post-shield lavas from the Mauna Kea and Kohala volcanoes, Hawaii  

SciTech Connect (OSTI)

Late Quaternary, post-shield lavas from the Mauna Kea and Kohala volcanoes on the Big Island of Hawaii have been dated using the {sup 40}Ar/{sup 39}Ar and U-Th/He methods. The objective of the study is to compare the recently demonstrated U-Th/He age method, which uses basaltic olivine phenocrysts, with {sup 40}Ar/{sup 39}Ar ages measured on groundmass from the same samples. As a corollary, the age data also increase the precision of the chronology of volcanism on the Big Island. For the U-Th/He ages, U, Th and He concentrations and isotopes were measured to account for U-series disequilibrium and initial He. Single analyses U-Th/He ages for Hamakua lavas from Mauna Kea are 87 {+-} 40 ka to 119 {+-} 23 ka (2{sigma} uncertainties), which are in general equal to or younger than {sup 40}Ar/{sup 39}Ar ages. Basalt from the Polulu sequence on Kohala gives a U-Th/He age of 354 {+-} 54 ka and a {sup 40}Ar/{sup 39}Ar age of 450 {+-} 40 ka. All of the U-Th/He ages, and all but one spurious {sup 40}Ar/{sup 39}Ar ages conform to the previously proposed stratigraphy and published {sup 14}C and K-Ar ages. The ages also compare favorably to U-Th whole rock-olivine ages calculated from {sup 238}U - {sup 230}Th disequilibria. The U-Th/He and {sup 40}Ar/{sup 39}Ar results agree best where there is a relatively large amount of radiogenic {sup 40}Ar (>10%), and where the {sup 40}Ar/{sup 36}Ar intercept calculated from the Ar isochron diagram is close to the atmospheric value. In two cases, it is not clear why U-Th/He and {sup 40}Ar/{sup 39}Ar ages do not agree within uncertainty. U-Th/He and {sup 40}Ar/{sup 39}Ar results diverge the most on a low-K transitional tholeiitic basalt with abundant olivine. For the most alkalic basalts with negligible olivine phenocrysts, U-Th/He ages were unattainable while {sup 40}Ar/{sup 39}Ar results provide good precision even on ages as low as 19 {+-} 4 ka. Hence, the strengths and weaknesses of the U-Th/He and {sup 40}Ar/{sup 39}Ar methods are complimentary for basalts with ages of order 100-500 ka.

Aciego, S.M.; Jourdan, F.; DePaolo, D.J.; Kennedy, B.M.; Renne, P.R.; Sims, K.W.W.

2009-10-01T23:59:59.000Z

213

TIDAL TAIL EJECTION AS A SIGNATURE OF TYPE Ia SUPERNOVAE FROM WHITE DWARF MERGERS  

SciTech Connect (OSTI)

The merger of two white dwarfs may be preceded by the ejection of some mass in ''tidal tails,'' creating a circumstellar medium around the system. We consider the variety of observational signatures from this material, which depend on the lag time between the start of the merger and the ultimate explosion (assuming one occurs) of the system in a Type Ia supernova (SN Ia). If the time lag is fairly short, then the interaction of the supernova ejecta with the tails could lead to detectable shock emission at radio, optical, and/or X-ray wavelengths. At somewhat later times, the tails produce relatively broad NaID absorption lines with velocity widths of the order of the white dwarf escape speed ({approx}1000 km s{sup -1}). That none of these signatures have been detected in normal SNe Ia constrains the lag time to be either very short ({approx}< 100 s) or fairly long ({approx}> 100 yr). If the tails have expanded and cooled over timescales {approx}10{sup 4} yr, then they could be observable through narrow NaID and Ca II H and K absorption lines in the spectra, which are seen in some fraction of SNe Ia. Using a combination of three-dimensional and one-dimensional hydrodynamical codes, we model the mass loss from tidal interactions in binary systems, and the subsequent interactions with the interstellar medium, which produce a slow-moving, dense shell of gas. We synthesize NaID line profiles by ray casting through this shell, and show that in some circumstances tidal tails could be responsible for narrow absorptions similar to those observed.

Raskin, Cody; Kasen, Daniel [Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA (United States)

2013-07-20T23:59:59.000Z

214

Especialista Universitario Java Enterprise 2010-2011 Depto. Ciencia de la Computacin e IA  

E-Print Network [OSTI]

Especialista Universitario Java Enterprise © 2010-2011 Depto. Ciencia de la Computación e IA Sesión 1: Introducción a JMS #12;Servicios de Mensajes con JMS © 2010-2011 Depto. Ciencia de la Computación · Una Aplicación JMS · PTP · Pub/Sub #12;Servicios de Mensajes con JMS © 2010-2011 Depto. Ciencia de la

Escolano, Francisco

215

IA --"-IScience Service Featuse 'I WHY T i E IJEAYIiER ?  

E-Print Network [OSTI]

No. 591 April 3 IA --"-IScience Service Featuse 'I WHY T i E IJEAYIiER ? II city located oa the Ice.pp';g a% Bidialo, The ice c h i l l s a t h i n laye:. of a i r aver the Sake aridto laewwd. NOW$ vhen r may be srrfficionl t o produce a sheet cloud and g i ~ eBuffalo a day not oalg dwnt arid chilly Lu

216

Experto Universitario Java Enterprise Componentes de presentacin 2012-2013 Depto. Ciencia de la Computacin e IA Sesin 1  

E-Print Network [OSTI]

Experto Universitario Java Enterprise Componentes de presentación © 2012-2013 Depto. Ciencia de la Universitario Java Enterprise Componentes de presentación © 2012-2013 Depto. Ciencia de la Computación e IA Componentes de presentación © 2012-2013 Depto. Ciencia de la Computación e IA Sesión 1 Experto Universitario

Escolano, Francisco

217

Especialista Universitario Java Enterprise Componentes de presentacin 2012-2013 Depto. Ciencia de la Computacin e IA Sesin 4  

E-Print Network [OSTI]

Especialista Universitario Java Enterprise Componentes de presentación © 2012-2013 Depto. Ciencia presentación © 2012-2013 Depto. Ciencia de la Computación e IA Sesión 4 Experto Universitario Java Enterprise Componentes de presentación © 2012-2013 Depto. Ciencia de la Computación e IA Sesión 4 Experto Universitario

Escolano, Francisco

218

Influence of Mo on the Fe:Mo:C nanocatalyst thermodynamics for single-walled carbon nanotube growth  

E-Print Network [OSTI]

ternary phases, such as the Fe,Mo 23C6 type carbides.37 The way in which carbon interacts with transition of metal carbide formation. Although relating C solubility and catalytic ability of metal catalysts,23 , metals which form carbides ca

Curtarolo, Stefano

219

Phonon and elastic instabilities in MoC and MoN Gus L. W. Hart* and Barry M. Klein  

E-Print Network [OSTI]

illustrating the rich behavior of carbo-nitride materials. The early transition metal carbides and nitrides high transition temperatures. We show that the elastic instability in B1-structure MoN, demonstrated the calculations re- ported here were performed with the linear-augmented- plane-wave method.2­4 The B1 carbides

Hart, Gus

220

Is the X-ray pulsating companion of HD 49798 a possible type Ia supernova progenitor?  

E-Print Network [OSTI]

HD 49798 (a hydrogen depleted subdwarf O6 star) with its massive white dwarf (WD) companion has been suggested to be a progenitor candidate of type Ia supernovae (SNe Ia). However, it is still uncertain whether the companion of HD 49798 is a carbon-oxygen (CO) WD or an oxygen-neon (ONe) WD. A CO WD will explode as an SN Ia when its mass grows approach to Chandrasekhar mass, while the outcome of an accreting ONe WD is likely to be a neutron star. We followed a series of Monte Carlo binary population synthesis approach to simulate the formation of ONe WD + He star systems. We found that there is almost no orbital period as large as HD 49798 with its WD companion in these ONe WD + He star systems based on our simulations, which means that the companion of HD 49798 might not be an ONe WD. We suggest that the companion of HD 49798 is most likely a CO WD, which can be expected to increase its mass to the Chandrasekhar mass limit by accreting He-rich material from HD 49798. Thus, HD 49798 with its companion may prod...

Liu, Dong-Dong; Wu, Cheng-Yuan; Wang, Bo

2015-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "ia mo ar" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Evaluation of copper for divider subassembly in MCO Mark IA and Mark IV scrap fuel baskets  

SciTech Connect (OSTI)

The K Basin Spent Nuclear Fuel (SNF) Project Multi-Canister Overpack (MCO) subprojection eludes the design and fabrication of a canister that will be used to confine, contain, and maintain fuel in a critically safe array to enable its removal from the K Basins, vacuum drying, transport, staging, hot conditioning, and interim storage (Goldinann 1997). Each MCO consists of a shell, shield plug, fuel baskets (Mark IA or Mark IV), and other incidental equipment. The Mark IA intact and scrap fuel baskets are a safety class item for criticality control and components necessary for criticality control will be constructed from 304L stainless steel. It is proposed that a copper divider subassembly be used in both Mark IA and Mark IV scrap baskets to increase the safety basis margin during cold vacuum drying. The use of copper would increase the heat conducted away from hot areas in the baskets out to the wall of the MCO by both radiative and conductive heat transfer means. Thus copper subassembly will likely be a safety significant component of the scrap fuel baskets. This report examines the structural, cost and corrosion consequences associated with using a copper subassembly in the stainless steel MCO scrap fuel baskets.

Graves, C.E.

1997-09-29T23:59:59.000Z

222

Observations of Type Ia Supernova 2014J with FLITECAM/SOFIA  

E-Print Network [OSTI]

We present medium resolution near-infrared (NIR) spectra, covering 1.1 to 3.4 microns, of the normal Type Ia supernova (SN Ia) SN 2014J in M82 obtained with the FLITECAM instrument aboard SOFIA approximately 17-25 days after maximum B light. Our 2.8-3.4 micron spectra may be the first ~3 micron spectra of a SN Ia ever published. The spectra spanning the 1.5-2.7 micron range are characterized by a strong emission feature at ~1.77 microns with a full width at half maximum of ~11,000-13,000 km/s. We compare the observed FLITECAM spectra to the recent non-LTE delayed detonation models of Dessart et al. (2014) and find that the models agree with the spectra remarkably well in the 1.5-2.7 micron wavelength range. Based on this comparison we identify the ~1.77 micron emission peak as a blend of permitted lines of Co II. Other features seen in the 2.0 - 2.5 micron spectra are also identified as emission from permitted transitions of Co II. However, the models are not as successful at reproducing the spectra in the 1....

Vacca, William D; Savage, Maureen; Shenoy, Sachindev; Becklin, E E; McLean, Ian S; Logsdon, Sarah E; Gehrz, R D; Spyromilio, J; Garnavich, P; Marion, G H; Fox, O D

2015-01-01T23:59:59.000Z

223

Observational constraints from SNe Ia and Gamma-Ray Bursts on a clumpy universe  

E-Print Network [OSTI]

The luminosity distance describing the effect of local inhomogeneities in the propagation of light proposed by Zeldovich-Kantowski-Dyer-Roeder (ZKDR) is tested with two probes for two distinct ranges of redshifts: supernovae Ia (SNe Ia) in 0.015 gamma-ray bursts (GRBs) in 1.547 < z < 3.57. Our analysis is performed by a Markov Chain Monte Carlo (MCMC) code that allows us to constrain the matter density parameter \\Omega_m as well as the smoothness parameter $\\alpha$ that measures the inhomogeneous-homogeneous rate of the cosmic fluid in a flat \\LambdaCDM model. The obtained best fits are (\\Omega_m=0.285^{+0.019}_{-0.018}, \\alpha= 0.856^{+0.106}_{-0.176}) from SNe Ia and (\\Omega_m=0.259^{+0.028}_{-0.028}, \\alpha=0.587^{+0.201}_{-0.202}) from GRBs, while from the joint analysis the best fits are (\\Omega_m=0.284^{+0.021}_{-0.020}, \\alpha= 0.685^{+0.164}_{-0.171}) with a \\chi^2_{\\rm red}=0.975. The value of the smoothness parameter $\\alpha$ indicates a clumped universe however it does not have an impact on the amount of dark energy (cosmological constant) needed to fit observations. This result may be an indication that the Dyer-Roeder approximation does not describe in a precise form the effects of clumpiness in the expansion of the universe.

Nora Bretón; Ariadna Montiel

2013-03-06T23:59:59.000Z

224

Single-crystal sup 40 Ar/ sup 39 Ar dating of the Olorgesailie Formation, southern Kenya rift  

SciTech Connect (OSTI)

Single-crystal laser fusion {sup 40}Ar/{sup 39}Ar analyses and several conventional bulk fusion {sup 40}K- {sup 40}Ar dates have been used to determine the age of volcaniclastic strata within the Olorgesailie Formation and of associated volcanic and sedimentary units of the southern Kenya rift. In the principal exposures along the southern edge of the Legemunge Plain, the formation spans the interval from approximately 500 to 1,000 ka. Deposition continued to the east along the Ol Keju Nyiro river where a tuff near the top of the formation has been dated at 215 ka. In these exposures, the formation is unconformably overlain by sediments dated at 49 ka. A possible source for the Olorgesailie tephra, the Ol Doinyo Nyokie volcanic complex, contains as ash flow dated at {approximately} 1 Ma, extending the known age range of this complex to encompass that of virtually the entire Olorgesailie Formation in the Legemunge Plain. These geologic examples illustrate the importance of the single-crystal {sup 40}Ar/{sup 39}Ar dating technique whereby contaminant, altered, or otherwise aberrant grains can be identified and eliminated from the determination of eruptive ages for reworked or altered pyroclastic deposits. The authors have presented a computer-modeling procedure based on an inverse-isochron analysis that promotes a more objective approach to trimming {sup 40}Ar/{sup 39}Ar isotope data sets of this type.

Deino, A. (Geochronology Center of the Inst. of Human Origins, Berkeley, CA (United States)); Potts, R. (Smithsonian Institution, Washington, DC (United States))

1990-06-10T23:59:59.000Z

225

Subclasses of Type Ia Supernovae as the origin of [\\alpha/Fe] ratios in dwarf spheroidal galaxies  

E-Print Network [OSTI]

Recent extensive observations of Type Ia Supernovae (SNe Ia) have revealed the existence of a diversity of SNe Ia, including SN 2002cx-like objects (also called SN Iax). We introduce two possible channels in the single degenerate scenario: 1) double detonations in sub-Chandrasekhar (Ch) mass CO white dwarfs (WDs), where a thin He envelope is developed with relatively low accretion rates after He novae even at low metallicities, and 2) carbon deflagrations in Ch-mass possibly hybrid C+O+Ne WDs, where WD winds occur at [Fe/H] ~ -2.5 at high accretion rates. These subclasses of SNe Ia are rarer than `normal' SNe Ia and do not affect the chemical evolution in the solar neighborhood, but can be very important in metal-poor systems with stochastic star formation. In dwarf spheroidal galaxies in the Local Group, the decrease of [\\alpha/Fe] ratios at [Fe/H] ~ -2 to -1.5 can be produced depending on the star formation history. SNe Iax give high [Mn/Fe], while sub-Ch-mass SNe Ia give low [Mn/Fe], and thus a model inclu...

Kobayashi, Chiaki; Hachisu, Izumi

2015-01-01T23:59:59.000Z

226

MUSCLE ACTIVITY DETECTION FROM MYOELECTRIC SIGNALS BASED ON THE AR-GARCH MODEL  

E-Print Network [OSTI]

MUSCLE ACTIVITY DETECTION FROM MYOELECTRIC SIGNALS BASED ON THE AR-GARCH MODEL Ghulam Rasool Heteroscedastic (AR-GARCH) process, which captures the heteroscedasticity of the signal. The Akaike information cri- terion test confirms that the AR-GARCH model better fits the EMG signal than the stationary AR

Bouaynaya, Nidhal

227

Scintillating bolometers based on ZnMoO$_4$ and Zn$^{100}$MoO$_4$ crystals to search for 0$\  

E-Print Network [OSTI]

The technology of scintillating bolometers based on zinc molybdate (ZnMoO$_4$) crystals is under development within the LUMINEU project to search for 0$\

Poda, D V; Arnaud, Q; Augier, C; Benoît, A; Bergé, L; Boiko, R S; Bergmann, T; Blümer, J; Broniatowski, A; Brudanin, V; Camus, P; Cazes, A; Censier, B; Chapellier, M; Charlieux, F; Chernyak, D M; Coron, N; Coulter, P; Cox, G A; Danevich, F A; de Boissière, T; Decourt, R; De Jesus, M; Devoyon, L; Drillien, A -A; Dumoulin, L; Eitel, K; Enss, C; Filosofov, D; Fleischmann, A; Fourches, N; Gascon, J; Gastaldo, L; Gerbier, G; Giuliani, A; Gros, M; Hehn, L; Henry, S; Hervé, S; Heuermann, G; Humbert, V; Ivanov, I M; Juillard, A; Kéfélian, C; Kleifges, M; Kluck, H; Kobychev, V V; Koskas, F; Kozlov, V; Kraus, H; Kudryavtsev, V A; Sueur, H Le; Loidl, M; Magnier, P; Makarov, E P; Mancuso, M; de Marcillac, P; Marnieros, S; Marrache-Kikuchi, C; Menshikov, A; Nasonov, S G; Navick, X-F; Nones, C; Olivieri, E; Pari, P; Paul, B; Penichot, Y; Pessina, G; Piro, M C; Plantevin, O; Redon, T; Robinson, M; Rodrigues, M; Rozov, S; Sanglard, V; Schmidt, B; Shlegel, V N; Siebenborn, B; Strazzer, O; Tcherniakhovski, D; Tenconi, M; Torres, L; Tretyak, V I; Vagneron, L; Vasiliev, Ya V; Velazquez, M; Viraphong, O; Walker, R J; Weber, M; Yakushev, E; Zhang, X; Zhdankov, V N

2015-01-01T23:59:59.000Z

228

NO. REV. MO. _ ALSEP/LCRU EMC Test Results  

E-Print Network [OSTI]

NO. REV. MO. ATM 1050 _ ALSEP/LCRU EMC Test Results PAGE 1 OF 10 DATE 19 August 1971 The results of the ALSEP/LCRU EMC test are reported in this ATM. C~.·--~ s--·~e'Jn~,__')!).Prepared by:__~~~"f--.;;.~-------- Approved by: ~JM.MD. ithian #12;NO. RIV. NO. ATM 1050 ALSEP/LCRU EMC Test Results 2 10PAGE OF Aall

Rathbun, Julie A.

229

Missouri Department of National Resources Energy Center Mo DNR | Open  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia: Energy Resources Jump to:46 -Energieprojekte GmbHMilo, Maine:Energy Information Energy Center Mo DNR Jump

230

IRRADIATION PERFORMANCE OF U-Mo MONOLITHIC FUEL  

SciTech Connect (OSTI)

High-performance research reactors require fuel that operates at high specific power to high fission density, but at relatively low temperatures. Research reactor fuels are designed for efficient heat rejection, and are composed of assemblies of thin-plates clad in aluminum alloy. The development of low-enriched fuels to replace high-enriched fuels for these reactors requires a substantially increased uranium density in the fuel to offset the decrease in enrichment. Very few fuel phases have been identified that have the required combination of very-high uranium density and stable fuel behavior at high burnup. UMo alloys represent the best known tradeoff in these properties. Testing of aluminum matrix U-Mo aluminum matrix dispersion fuel revealed a pattern of breakaway swelling behavior at intermediate burnup, related to the formation of a molybdenum stabilized high aluminum intermetallic phase that forms during irradiation. In the case of monolithic fuel, this issue was addressed by eliminating, as much as possible, the interfacial area between U-Mo and aluminum. Based on scoping irradiation test data, a fuel plate system composed of solid U-10Mo fuel meat, a zirconium diffusion barrier, and Al6061 cladding was selected for development. Developmental testing of this fuel system indicates that it meets core criteria for fuel qualification, including stable and predictable swelling behavior, mechanical integrity to high burnup, and geometric stability. In addition, the fuel exhibits robust behavior during power-cooling mismatch events under irradiation at high power.

M.K. Meyer; J. Gan; J.-F. Jue; D.D. Keiser; E. Perez; A. Robinson; D.M. Wachs; N. Woolstenhulme; G.L. Hofman; Y.-S. Kim

2014-04-01T23:59:59.000Z

231

Long-term corrosion of Cr-Mo steels in superheated steam at 482 and 538/sup 0/C. [21/4 Cr-1 Mo; 9 Cr-1 Mo; Sumitomo 9 Cr-2 Mo; Sandvik HT-9  

SciTech Connect (OSTI)

The corrosion of several Cr-Mo ferritic steels was investigated in superheated steam at an operating power plant. Tests were conducted at 482 and 538/sup 0/C (900 and 1000/sup 0/F) in a once-through loop for times up to 28,000 h. Chromium concentrations ranged from 2.0 to 11.3%, and the effect of surface preparation on corrosion was investigated. Only one of many specimens showed evidence of exfoliation at 482/sup 0/C, but at 538/sup 0/C exfoliation occurred on at least some of the specimens of most materials; the exceptions were the alloy with the highest chromium content (Sandvik HT-9), one heat of 9 Cr-1 Mo steel with the highest silicon content, and Sumitomo 9 Cr-2 Mo steel, which was in test for only 19,000 h. Parabolic oxidation kinetics adequately described the corrosion process for about the first year, after which corrosion rates were constant and lower than predicted from extrapolation of the initial part of the penetration versus time curves. With chromium concentrations between 2 and 9%, corrosion behavior was independent of chromium content, and corrosion was only slightly less with Sandvik HT-9. Corrosion was nearly independent of surface preparation, but in two cases the presence of mill scale on the surface prior to steam exposure seemed to retard oxidation in steam. 11 figures, 5 tables.

Griess, J.C.; DeVan, J.H.; Maxwell, W.A.

1980-01-01T23:59:59.000Z

232

Ion acceleration in Ar-Xe and Ar-He plasmas. I. Electron energy distribution functions and ion composition  

SciTech Connect (OSTI)

Electron energy distribution functions (eedf), ion production, and ion composition are studied in Ar-Xe and Ar-He expanding helicon plasmas. It was found that under the conditions of constant total flow rate, Xe, in addition to Ar, changes the eedf from Maxwellian-like to Druyvesteyn-like with a shortening of the high energy tail at {approx}15 eV. The electron temperature exponentially decreases from {approx}7 eV in pure Ar plasma to {approx}4 eV in pure Xe plasma. Xenon ions dominate the ion population for Xe filling fractions greater than 10%. The plasma density increases by {approx}15% with increasing Xe fraction. For an Ar-He plasma, increasing the helium fraction increases the electron temperature from {approx}7 eV in pure Ar plasma to {approx}14 eV for a He filling fraction of 80%. The plasma density drops by more than three orders of magnitude from 1.14x10{sup 11} cm{sup -3} to 6.5x10{sup 7} cm{sup -3}. However, the inferred ion densities indicate that even at a helium fraction of 80%, argon ions significantly outnumber helium ions.

Biloiu, Ioana A.; Scime, Earl E. [Department of Physics, West Virginia University, Morganton, West Virginia 26506 (United States)

2010-11-15T23:59:59.000Z

233

CIMAT, VI Escuela de verano, 25 de julio 7 de agosto 1999 Introducci'on a la Geometr'ia de la Mec'anica Cl'asica  

E-Print Network [OSTI]

parametrizada por (x(t); â?? x(t)): (d) Dibujar las gr'aficas de su energ'ia cin'etica T = ( â?? x) 2 =2 y potencial­ vaci'on de energ'ia, E = T + V = constante: (e) Repetir los 4 incisos anteriores con x(1) = 2; â?? x(0CIMAT, VI Escuela de verano, 25 de julio ­ 7 de agosto 1999 Introducci'on a la Geometr'ia de la Mec

Bor, Gil

234

CIMAT, VI Escuela de verano, 25 de julio -7 de agosto 1999 Introducci'on a la Geometr'ia de la Mec'anica Cl'asica  

E-Print Network [OSTI]

(t), `x(t)). (d)Dibujar las gr'aficas de su energ'ia cin'etica T = (x`)2=2 y potencial* * V = x2- vaci'on de energ'ia, E = T + V = constante. (e)Repetir los 4 incisos anteriores con x(1) = 2, `x CIMAT, VI Escuela de verano, 25 de julio - 7 de agosto 1999 Introducci'on a la Geometr'ia de la

Bor, Gil

235

1 Di Neujahr 1 Fr 1 Fr 1 Mo Ostermontag 2 Mi 2 Sa 2 Sa 2 Di  

E-Print Network [OSTI]

1 Di Neujahr 1 Fr 1 Fr 1 Mo Ostermontag 2 Mi 2 Sa 2 Sa 2 Di 3 Do 3 So 3 So 3 Mi 4 Fr 4 Mo 4 Mo 4 Do 5 Sa 5 Di 5 Di 5 Fr 6 So 6 Mi 6 Mi 6 Sa 7 Mo 7 Do 7 Do 7 So 8 Di 8 Fr 8 Fr 8 Mo 9 Mi 9 Sa 9 Sa 9 Di 10 Do 10 So 10 So 10 Mi 11 Fr 11 Mo 11 Mo 11 Do 12 Sa 12 Di 12 Di 12 Fr 13 So 13 Mi 13 Mi Power

Grübel, Rudolf

236

Single Phase Melt Processed Powellite (Ba,Ca) MoO{sub 4} For The Immobilization Of Mo-Rich Nuclear Waste  

SciTech Connect (OSTI)

Crystalline and glass composite materials are currently being investigated for the immobilization of combined High Level Waste (HLW) streams resulting from potential commercial fuel reprocessing scenarios. Several of these potential waste streams contain elevated levels of transition metal elements such as molybdenum (Mo). Molybdenum has limited solubility in typical silicate glasses used for nuclear waste immobilization. Under certain chemical and controlled cooling conditions, a powellite (Ba,Ca)MoO{sub 4} crystalline structure can be formed by reaction with alkaline earth elements. In this study, single phase BaMoO{sub 4} and CaMoO{sub 4} were formed from carbonate and oxide precursors demonstrating the viability of Mo incorporation into glass, crystalline or glass composite materials by a melt and crystallization process. X-ray diffraction, photoluminescence, and Raman spectroscopy indicated a long range ordered crystalline structure. In-situ electron irradiation studies indicated that both CaMoO{sub 4} and BaMoO{sub 4} powellite phases exhibit radiation stability up to 1000 years at anticipated doses with a crystalline to amorphous transition observed after 1 X 10{sup 13} Gy. Aqueous durability determined from product consistency tests (PCT) showed low normalized release rates for Ba, Ca, and Mo (<0.05 g/m{sup 2}).

Brinkman, Kyle [Savannah River Site (SRS), Aiken, SC (United States); Marra, James [Savannah River Site (SRS), Aiken, SC (United States); Fox, Kevin [Savannah River Site (SRS), Aiken, SC (United States); Reppert, Jason [Savannah River Site (SRS), Aiken, SC (United States); Crum, Jarrod [Paci fic Northwest National Laboratory , Richland, WA (United States); Tang, Ming [Los Alamos National Laboratory , Los Alamos, NM (United States)

2012-09-17T23:59:59.000Z

237

Pressure effect on the magnetization of Sr{sub 2}FeMoO{sub 6} thin films grown by pulsed laser deposition  

SciTech Connect (OSTI)

Thin films of Sr{sub 2}FeMoO{sub 6} (SFMO) are grown on SrTiO{sub 3} (001) substrates by pulsed laser deposition. The best films provide 3.2{mu}{sub B}/f.u. at 5 K, a Curie temperature above 400 K, low roughness, high crystallinity, and low splashing. Therefore, the use of such SFMO electrodes in magnetic tunnel junctions patterned with conventional lithography is promising. Pseudomorphic epitaxial growth is obtained for thicknesses under 50 nm. Above this thickness the films do not relax homogeneously. A coherent and systematic variation of the magnetization with the deposition conditions is obtained, which highlights a high reproducibility. Under a reasonable O{sub 2} partial pressure to avoid parasite phases, the limiting factor for high magnetization is the total pressure or the deposition rate. Therefore, the deposition rate is suspected to have a strong influence on the Fe/Mo ordering. Highly magnetic samples are obtained under a low gas flow of either a 20% O{sub 2}+N{sub 2} or a 0.3% O{sub 2}+Ar.

Fix, T.; Versini, G.; Loison, J.L.; Colis, S.; Schmerber, G.; Pourroy, G.; Dinia, A. [Institut de Physique et de Chimie des Materiaux de Strasbourg (IPCMS) Unite Mixte de Recherche 7504 du Centre National de la Recherche Scientifique (UMR 7504 du CNRS), Universite Louis Pasteur-Ecole Europeenne de Chimie, Polymeres et Materiaux de Strasbourg - ULP-ECPM, 23 rue du Loess BP43 F-67034 Strasbourg (France)

2005-01-15T23:59:59.000Z

238

IS WX CEN A POSSIBLE TYPE Ia SUPERNOVA PROGENITOR WITH WIND-DRIVEN MASS TRANSFER?  

SciTech Connect (OSTI)

WX Cen is one of a few compact binary supersoft X-ray sources (CBSS) in the Galaxy that is a possible Type Ia supernova (SN Ia) progenitor. The supersoft X-ray radiation is explained as hydrostatic nuclear burning on the surface of the white dwarf component that is accreting hydrogen from a stellar companion at a high rate. If the mass donor in this system has a low mass, as has been suggested in the literature, one would expect a high wind-driven mass transfer rate. In that case, the orbital period of the system should increase. To test this theoretical prediction, we have monitored the system photometrically since 2010. By using four newly determined eclipse timings together with those collected from the literature, we discovered that the orbital period is decreasing at a rate of dP/dt = -5.15 Multiplication-Sign 10{sup -7} days yr{sup -1}. The long-term decrease in the orbital period is contrary to the prediction that the system is powered by wind-driven accretion. It therefore seems plausible that the mass donor could be more massive than the white dwarf, and that the mass transfer is driven by the thermal instability of the donor star. This finding suggests that WX Cen is a key object to check the physical mechanisms of mass accretion in CBSS. The corresponding timescale of the period change is about P/P-dot {approx} 0.81 x 10{sup 6} yr, indicating that WX Cen may evolve into an SNe Ia within one million years in the Galaxy.

Qian, S.-B.; Shi, G.; Zhu, L.-Y.; Liu, L.; Zhao, E.-G.; Li, L.-J. [Yunnan Observatories, Chinese Academy of Sciences (CAS), P.O. Box 110, 650011 Kunming (China); Fernandez Lajus, E.; Di Sisto, R. P., E-mail: qsb@ynao.ac.cn [Facultad de Ciencias Astronomicas y Geofisicas, Universidad Nacional de La Plata, 1900 La Plata, Buenos Aires (Argentina)

2013-08-01T23:59:59.000Z

239

On the thermonuclear runaway in Type Ia supernovae: How to run away  

E-Print Network [OSTI]

Type Ia Supernovae are thought to be thermonuclear explosions of massive white dwarfs (WD). We present the first study of multi-dimensional effects during the final hours prior to the thermonuclear runaway which leads to the explosion. The calculations utilize an implicit, 2-D hydrodynamical code. Mixing and the ignition process are studied in detail. We find that the initial chemical structure of the WD is changed but the material is not fully homogenized. In particular, the exploding WD sustains a central region with a low C/O ratio. This implies that the explosive nuclear burning will begin in a partially carbon-depleted environment. The thermonuclear runaway happens in a well defined region close to the center. It is induced by compressional heat when matter is brought inwards by convective flows. We find no evidence for multiple spot or strong off-center ignition. Convective velocities in the WD are of the order of 100 km/sec which is well above the effective burning speeds in SNe Ia previously expected right after the runaway. For ? 0.5 to 1 sec, the speed of the burning front will neither be determined by the laminar speed nor the Rayleigh-Taylor instabilities but by convective flows produced prior to the runaway. The consequences are discussed for our understanding of the detailed physics of the flame propagation, the deflagration detonation transition, and the nucleosynthesis in the central layers. Our results strongly suggest the pre-conditioning of the progenitor as a key factor for our understanding of the diversity in Type Ia Supernovae.

P. Höflich; J. Stein

2002-01-01T23:59:59.000Z

240

On the Thermonuclear Runaway in Type Ia Supernovae: How to run away?  

E-Print Network [OSTI]

Type Ia Supernovae are thought to be thermonuclear explosions of massive white dwarfs (WD). We present the first study of multi-dimensional effects during the final hours prior to the thermonuclear runaway which leads to the explosion. The calculations utilize an implicit, 2-D hydro code.Mixing and the ignition process are studied in detail. We find that the initial chemical structure of the WD is changed but the material is not fully homogenized. The exploding WD sustains a central region with a low C/O ratio. This implies that the explosive nuclear burning will begin in a partially C-depleted environment. The thermonuclear runaway happens in a well defined region close to the center. It is induced by compressional heat when matter is brought inwards by convective flows. We find no evidence for multiple spot or strong off-center ignition. Convective velocities are of the order of 100 km/sec which is well above the effective burning speeds in SNe Ia previously expected right after the runaway. For about 0.5 to 1 sec, the speed of the burning front will neither be determined by the laminar speed nor the Rayleigh-Taylor instabilities but by convective flows produced prior to the runaway. The consequences are discussed for our under- standing of the detailed physics of the flame propagation, the deflagration detonation transition, and the nucleosynthesis in the central layers. Our results strongly suggest the pre-conditioning of the progenitor as a key-factor for our understanding of the diversity in SNeIa.

P. Hoeflich; J. Stein

2001-12-07T23:59:59.000Z

Note: This page contains sample records for the topic "ia mo ar" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

High-performance MoS{sub 2} transistors with low-resistance molybdenum contacts  

SciTech Connect (OSTI)

In this Letter, molybdenum (Mo) is introduced and evaluated as an alternative contact metal to atomically-thin molybdenum disulphide (MoS{sub 2}), and high-performance field-effect transistors are experimentally demonstrated. In order to understand the physical nature of the interface and highlight the role of the various factors contributing to the Mo-MoS{sub 2} contacts, density functional theory (DFT) simulations are employed, which reveal that Mo can form high quality contact interface with monolayer MoS{sub 2} with zero tunnel barrier and zero Schottky barrier under source/drain contact, as well as an ultra-low Schottky barrier (0.1?eV) at source/drain-channel junction due to strong Fermi level pinning. In agreement with the DFT simulations, high mobility, high ON-current, and low contact resistance are experimentally demonstrated on both monolayer and multilayer MoS{sub 2} transistors using Mo contacts. The results obtained not only reveal the advantages of using Mo as a contact metal for MoS{sub 2} but also highlight the fact that the properties of contacts with 2-dimensional materials cannot be intuitively predicted by solely considering work function values and Schottky theory.

Kang, Jiahao; Liu, Wei; Banerjee, Kaustav, E-mail: kaustav@ece.ucsb.edu [Department of Electrical and Computer Engineering, University of California, Santa Barbara, California 93106 (United States)

2014-03-03T23:59:59.000Z

242

The type Ia supernova SNLS-03D3bb from a super-Chandrasekhar-masswhite dwarf star  

SciTech Connect (OSTI)

The acceleration of the expansion of the universe, and theneed for Dark Energy, were inferred from the observations of Type Iasupernovae (SNe Ia) 1;2. There is consensus that SNeIa are thermonuclearexplosions that destroy carbon-oxygen white dwarf stars that accretematter from a companion star3, although the nature of this companionremains uncertain. SNe Ia are thought to be reliable distance indicatorsbecause they have a standard amount of fuel and a uniform trigger theyare predicted to explode when the mass of the white dwarf nears theChandrasekhar mass 4 - 1.4 solar masses. Here we show that the highredshift supernova SNLS-03D3bb has an exceptionally high luminosity andlow kinetic energy that both imply a super-Chandrasekhar mass progenitor.Super-Chandrasekhar mass SNeIa shouldpreferentially occur in a youngstellar population, so this may provide an explanation for the observedtrend that overluminous SNe Ia only occur in young environments5;6. Sincethis supernova does not obey the relations that allow them to becalibrated as standard candles, and since no counterparts have been foundat low redshift, future cosmology studies will have to considercontamination from such events.

Howell, D.Andrew; Sullivan, Mark; Nugent, Peter E.; Ellis,Richard S.; Conley, Alexander J.; Le Borgne, Damien; Carlberg, RaymondG.; Guy, Julien; Balam, David; Basa, Stephane; Fouchez, Dominique; Hook,Isobel M.; Hsiao, Eric Y.; Neill, James D.; Pain, Reynald; Perrett,Kathryn M.; Pritchet, Christopher J.

2006-02-01T23:59:59.000Z

243

A super-Eddington wind scenario for the progenitors of type Ia supernovae: binary population synthesis calculations  

E-Print Network [OSTI]

The super-Eddington wind scenario has been proposed as an alternative way for producing type Ia supernovae (SNe Ia). The super-Eddington wind can naturally prevent the carbon--oxygen white dwarfs (CO WDs) with high mass-accretion rates from becoming red-giant-like stars. Furthermore, it works in low-metallicity environments, which may explain SNe Ia observed at high redshifts. In this article, we systematically investigated the most prominent single-degenerate WD+MS channel based on the super-Eddington wind scenario. We combined the Eggleton stellar evolution code with a rapid binary population synthesis (BPS) approach to predict SN Ia birthrates for the WD+MS channel by adopting the super-Eddington wind scenario and detailed mass-accumulation efficiencies of H-shell flashes on the WDs. Our BPS calculations found that the estimated SN Ia birthrates for the WD+MS channel are ~0.009-0.315*10^{-3}{yr}^{-1} if we adopt the Eddington accretion rate as the critical accretion rate, which are much lower than that of ...

Wang, Bo; Liu, Dongdong; Liu, Zhengwei; Wu, Chengyuan; Zhang, Jujia; Han, Zhanwen

2015-01-01T23:59:59.000Z

244

Testing the isotropy of the Universe by using the JLA compilation of type-Ia supernovae  

E-Print Network [OSTI]

We probe the possible anisotropy in the accelerated expanding Universe by using the JLA compilation of type-Ia supernovae. We constrain the amplitude and direction of anisotropy in the anisotropic cosmological models. For the dipole-modulated $\\Lambda$CDM model, the anisotropic amplitude has an upper bound $D<1.04\\times10^{-3}$ at the $68\\%$ confidence level. Similar results are found in the dipole-modulated $w$CDM and CPL models. Our studies show that there are no significant evidence for the anisotropic expansion of the Universe. Thus the Universe is still well compatible with the isotropy.

Lin, Hai-Nan; Chang, Zhe; Li, Xin

2015-01-01T23:59:59.000Z

245

On the Stability of Thermonuclear Burning Fronts in Type Ia Supernovae  

E-Print Network [OSTI]

Summary. The propagation of cellularly stabilized thermonuclear flames is investigated by means of numerical simulations. In Type Ia supernova explosions the corresponding burning regime establishes at scales below the Gibson length. The cellular flame stabilization—which is a result of an interplay between the Landau-Darrieus instability and a nonlinear stabilization mechanism—is studied for the case of propagation into quiescent fuel as well as interaction with vortical fuel flows. Our simulations indicate that in thermonuclear supernova explosions stable cellular flames develop around the Gibson scale and that a deflagration-to-detonation transition is unlikely to be triggered from flame evolution effects here. 1

F. K. Röpke; W. Hillebr

2004-01-01T23:59:59.000Z

246

Reconstruction of Hessence Dark Energy and the Latest Type Ia Supernovae Gold Dataset  

E-Print Network [OSTI]

Recently, many efforts have been made to build dark energy models whose equation-of-state parameter can cross the so-called phantom divide $w_{de}=-1$. One of them is the so-called hessence dark energy model in which the role of dark energy is played by a non-canonical complex scalar field. In this work, we develop a simple method based on Hubble parameter $H(z)$ to reconstruct the hessence dark energy. As examples, we use two familiar parameterizations for $H(z)$ and fit them to the latest 182 type Ia supernovae Gold dataset. In the reconstruction, measurement errors are fully considered.

Hao Wei; Ningning Tang; Shuang Nan Zhang

2007-02-28T23:59:59.000Z

247

Reconstruction of a Deceleration Parameter from the Latest Type Ia Supernovae Gold Dataset  

E-Print Network [OSTI]

In this paper, a parameterized deceleration parameter $q(z)= 1/2 - a/(1 + z)^b$ is reconstructed from the latest type Ia supernovae gold dataset. It is found out that the transition redshift from decelerated expansion to accelerated expansion is at $z_T=0.35^{+0.14}_{-0.07}$ with $1\\sigma$ confidence level in this parameterized deceleration parameter. And, the best fit values of parameters in $1\\sigma$ errors are $a=1.56^{+0.99}_{-0.55}$ and $b=3.82^{+3.70}_{-2.27}$.

Lixin Xu; Chengwu Zhang; Baorong Chang; Hongya Liu

2007-01-17T23:59:59.000Z

248

Gamma-Rays as Probes for the Multi-Dimensionality of Type Ia Supernovae  

E-Print Network [OSTI]

We present $\\gamma $-ray spectra for a set of Type Ia supernovae models. Our study is based on a detailed Monte Carlo transport scheme for both spherical and full 3-D geometries. Classical and new challenges of the $\\gamma $ ray astronomy are addressed. We find that $\\gamma $-rays are very suitable to reveal the structure of the envelope and, thus, they allow to probe properties of the nuclear burning front and the progenitor, namely its central density and global asphericities. The potential problems are discussed for the quantitative comparison between theoretical and observed line fluxes during the first few months after the explosion.

P. Hoeflich

2001-10-03T23:59:59.000Z

249

On the Stability of Thermonuclear Burning Fronts in Type Ia Supernovae  

E-Print Network [OSTI]

The propagation of cellularly stabilized thermonuclear flames is investigated by means of numerical simulations. In Type Ia supernova explosions the corresponding burning regime establishes at scales below the Gibson length. The cellular flame stabilization - which is a result of an interplay between the Landau-Darrieus instability and a nonlinear stabilization mechanism - is studied for the case of propagation into quiescent fuel as well as interaction with vortical fuel flows. Our simulations indicate that in thermonuclear supernova explosions stable cellular flames develop around the Gibson scale and that deflagration-to-detonation transition is unlikely to be triggered from flame evolution effects here.

F. K. Roepke; W. Hillebrandt

2004-04-26T23:59:59.000Z

250

IA REP0 SAND85-2809 Unlimited Release UC-92A  

Office of Scientific and Technical Information (OSTI)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary)morphinan antagonist Journal Article: Crystal structureComposite--FORRemarksHEATINGI _ _ ORNL-6161 OAK*I.IA

251

File:USDA-CE-Production-GIFmaps-IA.pdf | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 NoPublicIDAPowerPlantSitingConstruction.pdfNotify98.pdf Jump to: navigation,storage plan reviewformP2.pdfFL.pdfIA.pdf

252

Production of 37Ar in The University of Texas TRIGA reactor facility  

SciTech Connect (OSTI)

The detection of {sup 37}Ar is important for on-site inspections for the Comprehensive Nuclear-Test-Ban Treaty monitoring. In an underground nuclear explosion this radionuclide is produced by {sup 40}Ca(n,{alpha}){sup 37}Ar reaction in surrounding soil and rock. With a half-life of 35 days, {sup 37}Ar provides a signal useful for confirming the location of an underground nuclear event. An ultra-low-background proportional counter developed by Pacific Northwest National Laboratory is used to detect {sup 37}Ar, which decays via electron capture. The irradiation of Ar gas at natural enrichment in the 3L facility within the Mark II TRIGA reactor facility at The University of Texas at Austin provides a source of {sup 37}Ar for the calibration of the detector. The {sup 41}Ar activity is measured by the gamma activity using an HPGe detector after the sample is removed from the core. Using the {sup 41}Ar/{sup 37}Ar production ratio and the {sup 41}Ar activity, the amount of {sup 37}Ar created is calculated. The {sup 41}Ar decays quickly (half-life of 109.34 minutes) leaving a radioactive sample of high purity {sup 37}Ar and only trace levels of {sup 39}Ar.

Egnatuk, Christine M.; Lowrey, Justin; Biegalski, S.; Bowyer, Ted W.; Haas, Derek A.; Orrell, John L.; Woods, Vincent T.; Keillor, Martin E.

2011-06-19T23:59:59.000Z

253

Inference for the dark energy equation of state using Type IA supernova data  

E-Print Network [OSTI]

The surprising discovery of an accelerating universe led cosmologists to posit the existence of "dark energy"--a mysterious energy field that permeates the universe. Understanding dark energy has become the central problem of modern cosmology. After describing the scientific background in depth, we formulate the task as a nonlinear inverse problem that expresses the comoving distance function in terms of the dark-energy equation of state. We present two classes of methods for making sharp statistical inferences about the equation of state from observations of Type Ia Supernovae (SNe). First, we derive a technique for testing hypotheses about the equation of state that requires no assumptions about its form and can distinguish among competing theories. Second, we present a framework for computing parametric and nonparametric estimators of the equation of state, with an associated assessment of uncertainty. Using our approach, we evaluate the strength of statistical evidence for various competing models of dark energy. Consistent with current studies, we find that with the available Type Ia SNe data, it is not possible to distinguish statistically among popular dark-energy models, and that, in particular, there is no support in the data for rejecting a cosmological constant. With much more supernova data likely to be available in coming years (e.g., from the DOE/NASA Joint Dark Energy Mission), we address the more interesting question of whether future data sets will have sufficient resolution to distinguish among competing theories.

Christopher Genovese; Peter Freeman; Larry Wasserman; Robert Nichol; Christopher Miller

2009-05-18T23:59:59.000Z

254

Variable Selection for Modeling the Absolute Magnitude at Maximum of Type Ia Supernovae  

E-Print Network [OSTI]

We discuss what is an appropriate set of explanatory variables in order to predict the absolute magnitude at the maximum of Type Ia supernovae. In order to have a good prediction, the error for future data, which is called the "generalization error," should be small. We use cross-validation in order to control the generalization error and LASSO-type estimator in order to choose the set of variables. This approach can be used even in the case that the number of samples is smaller than the number of candidate variables. We studied the Berkeley supernova database with our approach. Candidates of the explanatory variables include normalized spectral data, variables about lines, and previously proposed flux-ratios, as well as the color and light-curve widths. As a result, we confirmed the past understanding about Type Ia supernova: i) The absolute magnitude at maximum depends on the color and light-curve width. ii) The light-curve width depends on the strength of Si II. Recent studies have suggested to add more va...

Uemura, Makoto; Kawabata, S; Ikeda, Shiro; Maeda, Keiichi

2015-01-01T23:59:59.000Z

255

Smoothed Particle Hydrodynamics simulations of the core-degenerate scenario for Type Ia supernovae  

E-Print Network [OSTI]

The core-degenerate (CD) scenario for type Ia supernovae (SN Ia) involves the merger of the hot core of an asymptotic giant branch (AGB) star and a white dwarf, and might contribute a non-negligible fraction of all thermonuclear supernovae. Despite its potential interest, very few studies, and based on only crude simplifications, have been devoted to investigate this possible scenario, compared with the large efforts invested to study some other scenarios. Here we perform the first three-dimensional simulations of the merger phase, and find that this process can lead to the formation of a massive white dwarf, as required by this scenario. We consider two situations, according to the mass of the circumbinary disk formed around the system during the final stages of the common envelope phase. If the disk is massive enough, the stars merge on a highly eccentric orbit. Otherwise, the merger occurs after the circumbinary disk has been ejected and gravitational wave radiation has brought the stars close to the Roche...

Aznar-Siguán, G; Lorén-Aguilar, P; Soker, N; Kashi, A

2015-01-01T23:59:59.000Z

256

Spectroscopic Observations and Analysis of the Unusual Type Ia SN1999ac  

SciTech Connect (OSTI)

The authors present optical spectra of the peculiar Type Ia supernova (SN Ia) 1999ac. The data extend from -15 to +42 days with respect to B-band maximum and reveal an event that is unusual in several respects. prior to B-band maximum, the spectra resemble those of SN 1999aa, a slowly declining event, but possess stronger Si II and Ca II signatures (more characteristic of a spectroscopically normal SN). Spectra after B-band maximum appear more normal. The expansion velocities inferred from the Iron lines appear to be lower than average; whereas, the expansion velocity inferred from Calcium H and K are higher than average. The expansion velocities inferred from the Iron lines appear to be lower than average; whereas, the expansion velocity inferred from Calcium H and K are higher than average. The expansion velocities inferred from Si II are among the slowest ever observed, though SN 1999ac is not particularly dim. The analysis of the parameters v{sub 10}(Si II), R(Si II), v, and {Delta}m{sub 15} further underlines the unique characteristics of SN 1999ac. They find convincing evidence of C II {lambda}6580 in the day -15 spectrum with ejection velocity v > 16,000 km s{sup -1}, but this signature disappears by day -9. This rapid evolution at early times highlights the importance of extremely early-time spectroscopy.

Garavini, G.; Aldering, G.; Amadon, A.; Amanullah, R.; Astier,P.; Balland, C.; Blanc, G.; Conley, A.; Dahlen, T.; Deustua, S.E.; Ellis,R.; Fabbro, S.; Fadeyev, V.; Fan, X.; Folatelli, G.; Frye, B.; Gates,E.L.; Gibbons, R.; Goldhaber, G.; Goldman, B.; Goobar, A.; Groom, D.E.; Haissinski, J.; Hardin, D.; Hook, I.; Howell, D.A.; Kent, S.; Kim, A.G.; Knop, R.A.; Kowalski, M.; Kuznetsova, N.; Lee, B.C.; Lidman, C.; Mendez,J.; Miller, G.J.; Moniez, M.; Mouchet, M.; Mourao, A.; Newberg, H.; Nobili, S.; Nugent, P.E.; Pain, R.; Perdereau, O.; Perlmutter, S.; Quimby, R.; Regnault, N.; Rich, J.; Richards, G.T.; Ruiz-Lapuente, P.; Schaefer, B.E.; Schahmaneche, K.; Smith, E.; Spadafora, A.L.; Stanishev,V.; Thomas, R.C.; Walton, N.A.; Wang, L.; Wood-Vasey, W.M.

2005-07-12T23:59:59.000Z

257

Constraining the Type Ia Supernova Progenitor: The Search for Hydrogen in Nebular Spectra  

E-Print Network [OSTI]

Despite intense scrutiny, the progenitor system(s) that gives rise to Type Ia supernovae remains unknown. The favored theory invokes a carbon-oxygen white dwarf accreting hydrogen-rich material from a close companion until a thermonuclear runaway ensues that incinerates the white dwarf. However, simulations resulting from this single-degenerate, binary channel demand the presence of low-velocity H-alpha emission in spectra taken during the late nebular phase, since a portion of the companion's envelope becomes entrained in the ejecta. This hydrogen has never been detected, but has only rarely been sought. Here we present results from a campaign to obtain deep, nebular-phase spectroscopy of nearby Type Ia supernovae, and include multi-epoch observations of two events: SN 2005am (slightly subluminous) and SN 2005cf (normally bright). No H-alpha emission is detected in the spectra of either object. An upper limit of 0.01 M_Sun of solar abundance material in the ejecta is established from the models of Mattila et al. which, when coupled with the mass-stripping simulations of Marietta et al. and Meng et al. effectively rules out progenitor systems for these supernovae with secondaries close enough to the white dwarf to be experiencing Roche lobe overflow at the time of explosion. Alternative explanations for the absence of H-alpha emission, along with suggestions for future investigations necessary to confidently exclude them as possibilities, are critically evaluated.

Douglas C. Leonard

2007-10-16T23:59:59.000Z

258

First Evidence of Globular Cluster Formation from the Ejecta of Prompt Type Ia Supernovae  

E-Print Network [OSTI]

Recent spectroscopic observations of globular clusters (GCs) in the Large Magellanic Cloud (LMC) have discovered that one of the intermediate-age GC, NGC 1718 with [Fe/H]=-0.7 has an extremely low [Mg/Fe] ratio of ~-0.9. We propose that NGC 1718 was formed from the ejecta of type Ia supernovae (SNe Ia) mixed with very metal-poor ([Fe/H] <-1.3) gas about ~ 2 Gyr ago. The proposed scenario is shown to be consistent with the observed abundances of Fe-group elements such as Cr, Mn, and Ni. In addition, compelling evidence for asymptotic giant branch stars playing a role in chemical enrichment during this GC formation is found. We suggest that the origin of the metal-poor gas is closely associated with the efficient gas-transfer from the outer gas disk of the Small Magellanic Cloud to the LMC disk. We anticipate that the outer part of the LMC disk contains field stars exhibiting significantly low [Mg/Fe] ratios, formed through the same process as NGC 1718.

Tsujimoto, Takuji

2012-01-01T23:59:59.000Z

259

Verifying the Cosmological Utility of Type Ia Supernovae:Implications of a Dispersion in the Ultraviolet Spectra  

SciTech Connect (OSTI)

We analyze the mean rest-frame ultraviolet (UV) spectrum ofType Ia Supernovae(SNe) and its dispersion using high signal-to-noiseKeck-I/LRIS-B spectroscopyfor a sample of 36 events at intermediateredshift (z=0.5) discoveredby the Canada-France-Hawaii TelescopeSupernova Legacy Survey (SNLS). Weintroduce a new method for removinghost galaxy contamination in our spectra,exploiting the comprehensivephotometric coverage of the SNLS SNe and theirhost galaxies, therebyproviding the first quantitative view of the UV spectralproperties of alarge sample of distant SNe Ia. Although the mean SN Ia spectrumhas notevolved significantly over the past 40 percent of cosmic history,preciseevolutionary constraints are limited by the absence of acomparable sample ofhigh quality local spectra. The mean UV spectrum ofour z 0.5 SNe Ia and itsdispersion is tabulated for use in futureapplications. Within the high-redshiftsample, we discover significant UVspectral variations and exclude dust extinctionas the primary cause byexamining trends with the optical SN color. Although progenitormetallicity may drive some of these trends, the variations we see aremuchlarger than predicted in recent models and do not follow expectedpatterns.An interesting new result is a variation seen in the wavelengthof selected UVfeatures with phase. We also demonstrate systematicdifferences in the SN Iaspectral features with SN lightcurve width inboth the UV and the optical. Weshow that these intrinsic variations couldrepresent a statistical limitation in thefuture use of high-redshift SNeIa for precision cosmology. We conclude thatfurther detailed studies areneeded, both locally and at moderate redshift wherethe rest-frame UV canbe studied precisely, in order that future missions canconfidently beplanned to fully exploit SNe Ia as cosmological probes.

Ellis, R.S.; Sullivan, M.; Nugent, P.E.; Howell, D.A.; Gal-Yam,A.; Astier, P.; Balam, D.; Balland, C.; Basa, S.; Carlberg, R.G.; Conley,A.; Fouchez, D.; Guy, J.; Hardin, D.; Hook, I.; Pain, R.; Perrett, K.; Pritchet, C.J.; Regnault, N.

2007-11-02T23:59:59.000Z

260

Greenfield Alternative Study LEU-Mo Fuel Fabrication Facility  

SciTech Connect (OSTI)

This report provides the initial “first look” of the design of the Greenfield Alternative of the Fuel Fabrication Capability (FFC); a facility to be built at a Greenfield DOE National Laboratory site. The FFC is designed to fabricate LEU-Mo monolithic fuel for the 5 US High Performance Research Reactors (HPRRs). This report provides a pre-conceptual design of the site, facility, process and equipment systems of the FFC; along with a preliminary hazards evaluation, risk assessment as well as the ROM cost and schedule estimate.

Washington Division of URS

2008-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "ia mo ar" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Structural Insights into FeMo Cofactor Biosynthesis  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administrationcontroller systemsBiSiteNeutronStrategic PlanStructuralMethodologyInsights into FeMo

262

Conceptual design of a new homogeneous reactor for medical radioisotope Mo-99/Tc-99m production  

SciTech Connect (OSTI)

To partly solve the global and regional shortages of Mo-99 supply, a conceptual design of a nitrate-fuel-solution based homogeneous reactor dedicated for Mo-99/Tc-99m medical radioisotope production is proposed. The modified LEU Cintichem process for Mo-99 extraction which has been licensed and demonstrated commercially for decades by BATAN is taken into account as a key design consideration. The design characteristics and main parameters are identified and the advantageous aspects are shown by comparing with the BATAN's existing Mo-99 supply chain which uses a heterogeneous reactor (RSG GAS multipurpose reactor)

Liem, Peng Hong [Nippon Advanced Information Service (NAIS Co., Inc.) Scientific Computational Division, 416 Muramatsu, Tokaimura, Ibaraki (Japan); Tran, Hoai Nam [Chalmers University of Technology, Dept. of Applied Physics, Div. of Nuclear Engineering, SE-412 96 Gothenburg (Sweden); Sembiring, Tagor Malem [National Nuclear Energy Agency (BATAN), Center for Reactor Technology and Nuclear Safety, Kawasan Puspiptek, Serpong, Tangerang Selatan, Banten (Indonesia); Arbie, Bakri [PT MOTAB Technology, Kedoya Elok Plaza Blok DA 12, Jl. Panjang, Kebun Jeruk, Jakarta Barat (Indonesia)

2014-09-30T23:59:59.000Z

263

Oxidation Behavior of Mo-Si-B Alloys in Wet Air  

SciTech Connect (OSTI)

Multiphase composite alloys based on the Mo-Si-B system are candidate materials for ultra-high temperature applications. In non load-bearing uses such as thermal barrier coatings or heat exchangers in fossil fuel burners, these materials may be ideally suited. The present work investigated the effect of water vapor on the oxidation behavior of Mo-Si-B phase assemblages. Three alloys were studied: Alloy 1 = Mo{sub 5}Si{sub 3}B{sub x} (T1)- MoSi{sub 2}- MoB, Alloy 2 = T1- Mo{sub 5}SiB{sub 2} (T2)- Mo{sub 3}Si, and Alloy 3 = Mo- T2- Mo{sub 3}Si. Tests were conducted at 1000 and 1100C in controlled atmospheres of dry air and wet air nominally containing 18, 55, and 150 Torr H{sub 2}O. The initial mass loss of each alloy was approximately independent of the test temperature and moisture content of the atmosphere. The magnitude of these initial losses varied according to the Mo content of the alloys. All alloys formed a continuous, external silica scale that protected against further mass change after volatilization of the initially formed MoO{sub 3}. All alloys experienced a small steady state mass change, but the calculated rates cannot be quantitatively compared due to statistical uncertainty in the individual mass measurements. Of particular interest is that Alloy 3, which contains a significant volume fraction of Mo metal, formed a protective scale. All alloys formed varying amounts of subscale Mo and MoO{sub 2}. This implies that oxygen transport through the external silica scale has been significantly reduced. For all alloys, water vapor accelerated the growth of a multiphase interlayer at the silica scale/unoxidized alloy interface. This interlayer is likely composed of fine Mo and MoO{sub 2} that is dispersed within a thin silica matrix. Alloy 3 was particularly sensitive to water accelerated growth of this interlayer. At 1100 C, the scale thickness after 300 hours increased from about 20 mm in dry air to nearly 100 mm in wet air.

M. Kramer; A. Thom; O. Degirmen; V. Behrani; M. Akinc

2002-04-22T23:59:59.000Z

264

Experimental activities supporting commercial U.S. accelerator production of 99-Mo  

SciTech Connect (OSTI)

{sup 99m}Tc, the daughter product of {sup 99}Mo, is the most commonly used radioisotope for nuclear medicine in the U.S. Experiments are being performed at Los Alamos National Laboratory and Argonne National Laboratory to demonstrate production of {sup 99}Mo using accelerators. The {sup 100}Mo({gamma},n){sup 99}Mo reaction in an enriched {sup 100}Mo target is currently under investigation. Three scaled low-power production experiments using a 20-MeV electron linac at Argonne have been performed to date. Two of these experiments used natural Mo targets and produced a total of 613 {mu}C of {sup 99}Mo. The third experiment used an enriched {sup 100}Mo target and produced 10.5 mCi of {sup 99}Mo. Following irradiation the targets were dissolved and the low specific activity solution was processed through an ARSII generator from NorthStar Medical Radioisotopes. Yields of {sup 99m}Tc >95% have been observed.

Dale, Gregory E [Los Alamos National Laboratory; Chemerisov, Sergey D [ANL; Vandegrift, George F [ANL

2010-01-01T23:59:59.000Z

265

CIMAT, VIII Escuela de verano, 30 de julio -10 de ago* Introducci'on a la Geometr'ia de la Mec'ani*  

E-Print Network [OSTI]

conservativo. 18.Sea A(E) el 'area dentro de una curva de fase cerrada que corresponde a nive* *l de energ'ia Introducci'on a la Geometr'ia de la Mec'ani* *ca Cl'asica Problemas 13 - 19

Bor, Gil

266

Thermal History of the Felsite Unit, Geysers Geothermal Field, From Thermal Modeling of 40Ar/39Ar Incremental Heating Data  

SciTech Connect (OSTI)

An Ar-40/Ar-39 and U-Pb study was performed of the Geysers plutonic complex of the Geysers Geothermal Field in California. Sixty-nine ion microprobe spot analyses of zircons from four granite samples from the plutonic complex that underlies the Geysers geothermal field yielded Pb-207/Pb-206 vs. U-238/Pb-206 concordia ages ranging from 1.13 {+-} 0.04 Ma to 1.25 {+-} 0.04 Ma. The U-Pb ages coincide closely with Ar-40/Ar-39 age spectrum plateau and ''terminal'' ages from coexisting K-feldspars and with the eruption ages of overlying volcanic rocks. The data indicate that the granite crystallized at 1.18 Ma and had cooled below 350 C by {approximately}0.9-1.0 Ma. Interpretation of the feldspar Ar-40/Ar-39 age data using multi-diffusion domain theory indicates that post-emplacement rapid cooling was succeeded either by slower cooling from 350-300 C between 1.0 and 0.4 Ma or transitory reheating to 300-350 C at about 0.4-0.6 Ma. Heat flow calculations constrained with K-feldspar thermal histories and the pre sent elevated regional heal flow anomaly demonstrate that appreciable heat input from sources external to the known Geysers plutonic complex is required to maintain the geothermal system. This requirement is satisfied by either a large, underlying, convecting magma chamber (now solidified) emplaced at 1.2 Ma or episodic intrusion of smaller bodies from 1.2-0.6 Ma.

T. M. Harrison (U of California); G. B. Dalrymple (Oregon State U); J. B. Hulen (U of Utah); M. A. Lanphere; M. Grove; O. M. Lovera

1999-08-19T23:59:59.000Z

267

A Generalized {ital K} Correction for Type Ia Supernovae: Comparing {ital R}-band Photometry Beyond {ital z=9.2} with B,V, and {ital R}-band Nearby Photometry  

E-Print Network [OSTI]

spectroscopically peculiar supernovae, and to search for anyK Correction for Type Ia Supernovae: Comparing R-bandK Correction for Type Ia Supernovae: Comparing R-band

Goodbar, Ariel

2008-01-01T23:59:59.000Z

268

Reaction propagation physics of AL/Mo0? nanocomposite thermites.  

SciTech Connect (OSTI)

Recent advances in the field of nmo-technology have focused intense interest on developing nano-scale energetic materials with potentially new and technologically useful characteristics. Despite the growing importance of nano-scale energetic materials, however, general combustion chmcteristics of ithese materials are not yet well characterized or understood. This study experimentally examines the mechanisms and phenomena that govern thermal and chemical proce!;ses associated with nano-structured energetic material combustion. Specifically, the general combusticm behavior of nanocornposite Al/MoO3 samples was observed. The composite material was prepared fiom nano-scale aluminum and molybdenum trioxide. Open combustion and confined burning were considered. Ai/Mo03 powder or pellet samples were ignited at one end in an open burxi tway and a high-speed imaging system recorded the flame propagation. Reaction behaviors were characterized from this photographic data. The goal was to obtain an improved understanding of flow pattenis (e.g., flame propagation mechanisms) associated with nano-structured energetic materials. These materials are shown to propagate at very high rates (>I 00 ids). E3ulk density effects on propagation rate iri these materials were found to be significant. Results from this study, and continuing work, could have an impact on the handling and application of nano-scala mergetic materials, and will eventually lead to a significantly improved understanding of this class of materials.

Asay, B. W. (Blaine W.); Busse, J. R. (James R.); Jorgensen, B. S. (Betty S.); Bockmon, B. (Bryan); Pantoya, M. (Michelle); Son, S. F. (Steven F.)

2001-01-01T23:59:59.000Z

269

Characterization of U-Mo Foils for AFIP-7  

SciTech Connect (OSTI)

Twelve AFIP in-process foil samples, fabricated by either Y-12 or LANL, were shipped from LANL to PNNL for potential characterization using optical and scanning electron microscopy techniques. Of these twelve, nine different conditions were examined to one degree or another using both techniques. For this report a complete description of the results are provided for one archive foil from each source of material, and one unirradiated piece of a foil of each source that was irradiated in the Advanced Test Reactor. Additional data from two other LANL conditions are summarized in very brief form in an appendix. The characterization revealed that all four characterized conditions contained a cold worked microstructure to different degrees. The Y-12 foils exhibited a higher degree of cold working compared to the LANL foils, as evidenced by the highly elongated and obscure U-Mo grain structure present in each foil. The longitudinal orientations for both of the Y-12 foils possesses a highly laminar appearance with such a distorted grain structure that it was very difficult to even offer a range of grain sizes. The U-Mo grain structure of the LANL foils, by comparison, consisted of a more easily discernible grain structure with a mix of equiaxed and elongated grains. Both materials have an inhomogenous grain structure in that all of the characterized foils possess abnormally coarse grains.

Edwards, Danny J.; Ermi, Ruby M.; Schemer-Kohrn, Alan L.; Overman, Nicole R.; Henager, Charles H.; Burkes, Douglas; Senor, David J.

2012-11-07T23:59:59.000Z

270

Smartphone-Mediated Tourist Experiences: Understanding the Influence of Augmented Reality (AR) Applications in Tourism  

E-Print Network [OSTI]

The synergy of smartphone, mobile applications (apps) and Augmented Reality (AR) technology has the potential to mediate tourism experiences to great extents. The advent of AR apps on smartphones provides a dynamic solution for tourists by helping...

Anuar, Faiz Izwan

2013-04-25T23:59:59.000Z

271

E-Print Network 3.0 - ar dadm elektronu Sample Search Results  

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

PRECATACLYSMIC VARIABLE BINARY1,2 Summary: calibration was established with HeAr arc-lamp spectra, in- terpolated between exposures taken before... to reduce the data. ThAr...

272

LATE-TIME SPECTRAL OBSERVATIONS OF THE STRONGLY INTERACTING TYPE Ia SUPERNOVA PTF11kx  

SciTech Connect (OSTI)

PTF11kx was a Type Ia supernova (SN Ia) that showed time-variable absorption features, including saturated Ca II H and K lines that weakened and eventually went into emission. The strength of the emission component of H{alpha} gradually increased, implying that the SN was undergoing significant interaction with its circumstellar medium (CSM). These features, and many others, were blueshifted slightly and showed a P-Cygni profile, likely indicating that the CSM was directly related to, and probably previously ejected by, the progenitor system itself. These and other observations led Dilday et al. to conclude that PTF11kx came from a symbiotic nova progenitor like RS Oph. In this work we extend the spectral coverage of PTF11kx to 124-680 rest-frame days past maximum brightness. The late-time spectra of PTF11kx are dominated by H{alpha} emission (with widths of full width at half-maximum intensity Almost-Equal-To 2000 km s{sup -1}), strong Ca II emission features ({approx}10,000 km s{sup -1} wide), and a blue 'quasi-continuum' due to many overlapping narrow lines of Fe II. Emission from oxygen, He I, and Balmer lines higher than H{alpha} is weak or completely absent at all epochs, leading to large observed H{alpha}/H{beta} intensity ratios. The H{alpha} emission appears to increase in strength with time for {approx}1 yr, but it subsequently decreases significantly along with the Ca II emission. Our latest spectrum also indicates the possibility of newly formed dust in the system as evidenced by a slight decrease in the red wing of H{alpha}. During the same epochs, multiple narrow emission features from the CSM temporally vary in strength. The weakening of the H{alpha} and Ca II emission at late times is possible evidence that the SN ejecta have overtaken the majority of the CSM and agrees with models of other strongly interacting SNe Ia. The varying narrow emission features, on the other hand, may indicate that the CSM is clumpy or consists of multiple thin shells.

Silverman, Jeffrey M. [Department of Astronomy, University of Texas, Austin, TX 78712-0259 (United States); Nugent, Peter E.; Filippenko, Alexei V.; Cenko, S. Bradley [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Gal-Yam, Avishay [Benoziyo Center for Astrophysics, The Weizmann Institute of Science, Rehovot 76100 (Israel); Sullivan, Mark [School of Physics and Astronomy, University of Southampton, Southampton SO17 1BJ (United Kingdom); Howell, D. Andrew [Las Cumbres Observatory Global Telescope Network, Goleta, CA 93117 (United States); Pan, Yen-Chen; Hook, Isobel M., E-mail: jsilverman@astro.as.utexas.edu [Department of Physics (Astrophysics), University of Oxford, Keble Road, Oxford OX1 3RH (United Kingdom)

2013-08-01T23:59:59.000Z

273

Supercapacitor behavior of ?-MnMoO{sub 4} nanorods on different electrolytes  

SciTech Connect (OSTI)

Graphical abstract: SEM image of ?-MnMoO{sub 4} nanorods on FTO substrate. Highlights: ? Synthesis of ?-MnMoO{sub 4} nanorods by spin coating method. ? First study on the effect of electrolyte on the pseudocapacitance behavior. ? ?-MnMoO{sub 4} nanorods exhibit maximum specific capacitance of 998 F/g. ? At higher scan rates p-TSA electrolyte exhibits superior capacitive behavior. -- Abstract: ?-MnMoO{sub 4} nanorods were prepared on conducting glass substrate via sol–gel spin coating method at the optimum doping level. The effect of electrolyte on the pseudocapacitance behavior of the ?-MnMoO{sub 4} nanorods was studied using para toluene sulfonic acid (p-TSA), sulfuric acid (H{sub 2}SO{sub 4}) and hydrochloric acid (HCl) as electrolytes. X-ray diffraction analysis reveals the formation of ?-MnMoO{sub 4} in monoclinic phase. FTIR spectra contain vibrational bands associated with Mo=O, M–O and Mo–O–Mo bonds. SEM image reveals the formation of nanorods. Supercapacitor behavior has been studied using cyclic voltammetry (CV) analysis. ?-MnMoO{sub 4} nanorods exhibit maximum specific capacitance of 998 F/g at a scan rate of 5 mV/s in H{sub 2}SO{sub 4} electrolyte while a specific capacitance of 784 F/g and 530 F/g have been obtained using p-TSA and HCl electrolytes, respectively. At higher scan rates p-TSA electrolyte exhibits superior capacitive behavior than H{sub 2}SO{sub 4}.

Purushothaman, K.K., E-mail: purushoth_gri@yahoo.co.in [Department of Physics, TRP Engineering College (SRM Group), Irungalur, Trichy, Tamilnadu (India); Cuba, M. [Department of Physics, Gandhigram Rural Institute – Deemed University, Gandhigram, Tamilnadu (India)] [Department of Physics, Gandhigram Rural Institute – Deemed University, Gandhigram, Tamilnadu (India); Muralidharan, G., E-mail: muralg@rediffmail.com [Department of Physics, Gandhigram Rural Institute – Deemed University, Gandhigram, Tamilnadu (India)

2012-11-15T23:59:59.000Z

274

Development of FeNiMoB thin film materials for microfabricated magnetoelastic sensors  

SciTech Connect (OSTI)

Metglas{sup TM} 2826MB foils of 25-30 {mu}m thickness with the composition of Fe{sub 40}Ni{sub 38}Mo{sub 4}B{sub 18} have been used for magnetoelastic sensors in various applications over many years. This work is directed at the investigation of {approx}3 {mu}m thick iron-nickel-molybdenum-boron (FeNiMoB) thin films that are intended for integrated microsystems. The films are deposited on Si substrate by co-sputtering of iron-nickel (FeNi), molybdenum (Mo), and boron (B) targets. The results show that dopants of Mo and B can significantly change the microstructure and magnetic properties of FeNi materials. When FeNi is doped with only Mo its crystal structure changes from polycrystalline to amorphous with the increase of dopant concentration; the transition point is found at about 10 at. % of Mo content. A significant change in anisotropic magnetic properties of FeNi is also observed as the Mo dopant level increases. The coercivity of FeNi films doped with Mo decreases to a value less than one third of the value without dopant. Doping the FeNi with B together with Mo considerably decreases the value of coercivity and the out-of-plane magnetic anisotropy properties, and it also greatly changes the microstructure of the material. In addition, doping B to FeNiMo remarkably reduces the remanence of the material. The film material that is fabricated using an optimized process is magnetically as soft as amorphous Metglas{sup TM} 2826MB with a coercivity of less than 40 Am{sup -1}. The findings of this study provide us a better understanding of the effects of the compositions and microstructure of FeNiMoB thin film materials on their magnetic properties.

Liang Cai; Gooneratne, Chinthaka; Cha, Dongkyu; Chen Long; Kosel, Jurgen [Computer Electrical and Mathematical Sciences and Engineering, King Abdullah University of Science and Technology, 4700 KAUST, Thuwal 23955 (Saudi Arabia); Gianchandani, Yogesh [Department of Electrical Engineering and Computer Science, 1301 Beal Ave., University of Michigan, Ann Arbor, Michigan 48109 (United States)

2012-12-01T23:59:59.000Z

275

SPECIA L SECTION D EP AR TM ENTS  

E-Print Network [OSTI]

#12;#12;SPECIA L SECTION D EP AR TM ENTS 20 Report on Research 22 Spotlight on Students 34 Focus of Phi Ep's national organization. Two lettersin particular stood outbecause they reported that the brothers of Phi Ep weren't the onlyfraternities at UConn to take a similarstand. N.C.Heilman '44 (ENG

Holsinger, Kent

276

DESY 07176 arXiv:0710.2602v1  

E-Print Network [OSTI]

########### DESY 07­176 arXiv:0710.2602v1 [hep­ex] 13 Oct 2007 Prospects to Measure the Higgs Boson - Germany The process e + e ! ZH allows to measure the Higgs boson in the recoil mass spectrum against the Z boson without any assumptions on the Higgs boson decay. We performed a full simulation

277

Utilizing the Updated Gamma-Ray Bursts and Type Ia Supernovae to Constrain the Cardassian Expansion Model and Dark Energy  

E-Print Network [OSTI]

We update gamma-ray burst (GRB) luminosity relations among certain spectral and light-curve features with 139 GRBs. The distance modulus of 82 GRBs at $z>1.4$ can be calibrated with the sample at $z\\leq1.4$ by using the cubic spline interpolation method from the Union2.1 Type Ia supernovae (SNe Ia) set. We investigate the joint constraints on the Cardassian expansion model and dark energy with 580 Union2.1 SNe Ia sample ($z<1.4$) and 82 calibrated GRBs data ($1.4Ia significantly improves the constrain on $\\Omega_{m}-\\Omega_{\\Lambda}$ plane. In the Cardassian expansion model, the best fit is $\\Omega_{m}= 0.24_{-0.15}^{+0.15}$ and $n=0.16_{-0.52}^{+0.30}$ $(1\\sigma)$, which is consistent with the $\\Lambda$CDM cosmology $(n=0)$ in the $1\\sigma$ confidence region. We also discuss two dark energy models in which the equation of state $w(z)$ is parametrized as $w(z)=w_{0}$ and $w(z)=w_{0}+w_{1}z/(1+z)$, respectively. Based on o...

Wei, Jun-Jie; Wu, Xue-Feng

2015-01-01T23:59:59.000Z

278

Experto Universitario Java Enterprise Validacin e internacionalizacin 2012-2013 Depto. Ciencia de la Computacin e IA Spring  

E-Print Network [OSTI]

Experto Universitario Java Enterprise Validación e internacionalización © 2012-2013 Depto. Ciencia #12;Experto Universitario Java Enterprise Validación e internacionalización © 2012-2013 Depto. Ciencia Java Enterprise Validación e internacionalización © 2012-2013 Depto. Ciencia de la Computación e IA

Escolano, Francisco

279

RESULTS OF THE LICK OBSERVATORY SUPERNOVA SEARCH FOLLOW-UP PHOTOMETRY PROGRAM: BVRI LIGHT CURVES OF 165 TYPE Ia SUPERNOVAE  

SciTech Connect (OSTI)

We present BVRI light curves of 165 Type Ia supernovae (SNe Ia) from the Lick Observatory Supernova Search follow-up photometry program from 1998 through 2008. Our light curves are typically well sampled (cadence of 3-4 days) with an average of 21 photometry epochs. We describe our monitoring campaign and the photometry reduction pipeline that we have developed. Comparing our data set to that of Hicken et al., with which we have 69 overlapping supernovae (SNe), we find that as an ensemble the photometry is consistent, with only small overall systematic differences, although individual SNe may differ by as much as 0.1 mag, and occasionally even more. Such disagreement in specific cases can have significant implications for combining future large data sets. We present an analysis of our light curves which includes template fits of light-curve shape parameters useful for calibrating SNe Ia as distance indicators. Assuming the B - V color of SNe Ia at 35 days past maximum light can be presented as the convolution of an intrinsic Gaussian component and a decaying exponential attributed to host-galaxy reddening, we derive an intrinsic scatter of {sigma} = 0.076 {+-} 0.019 mag, consistent with the Lira-Phillips law. This is the first of two papers, the second of which will present a cosmological analysis of the data presented herein.

Ganeshalingam, Mohan; Li Weidong; Filippenko, Alexei V.; Anderson, Carmen; Foster, Griffin; Griffith, Christopher V.; Joubert, Niels; Leja, Joel; Macomber, Brent; Pritchard, Tyler; Thrasher, Patrick; Winslow, Dustin [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Gates, Elinor L.; Grigsby, Bryant J.; Lowe, Thomas B. [Lick Observatory, P.O. Box 85, Mount Hamilton, CA 95140 (United States)

2010-10-15T23:59:59.000Z

280

CS3600 Lab Manual CyberCIEGE is an information assurance (IA) training tool that illustrates computer and  

E-Print Network [OSTI]

CS3600 Lab Manual Lab SSL CyberCIEGE is an information assurance (IA) training tool. The CyberCIEGE SSL scenario illustrates the use of SSL to authenticate the identity of web servers. This scenario explores the following concepts: · SSL is a means of authenticating a server (e.g., a web server

Note: This page contains sample records for the topic "ia mo ar" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

ANALYSIS OF LIMIT CYCLE STABILITY IN A TAP-CHANGING TRANSFORMER V. Donde I.A. Hiskens  

E-Print Network [OSTI]

ANALYSIS OF LIMIT CYCLE STABILITY IN A TAP-CHANGING TRANSFORMER V. Donde I.A. Hiskens Department of transformer tap changing and load dynamics. Lin- earization of a Poincar´e map is used to prove local of the region of attraction can then be obtained. 1. INTRODUCTION Interactions between tap-changing transformers

Hiskens, Ian A.

282

The arXiv: 14 years of open access scientific communication Simeon Warner  

E-Print Network [OSTI]

/09/14 20:22:09 Abstract The arXiv was started in 1991 as a way for high-energy physicists to share publishing. Lessons learned from this development include the importance of community and critical mass how journal publishers have reacted to the arXiv, and ask what the arXiv reveals about the established

Warner, Simeon

283

Le magn)sme ar)ficiel pour les gaz d'atomes froids Jean Dalibard  

E-Print Network [OSTI]

Le magné)sme ar)ficiel pour les gaz d'atomes froids Jean Dalibard Année 2013-14 Chaire Atomes et rayonnement Magné8sme ar8ficiel pour un atome isolé poten8el vecteur et la simula8on du magné8sme orbital A(r) V

Dalibard, Jean

284

Type Ia Supernova Intrinsic Magnitude Dispersion and the Fitting of Cosmological Parameters  

SciTech Connect (OSTI)

I present an analysis for fitting cosmological parameters from a Hubble Diagram of a standard candle with unknown intrinsic magnitude dispersion. The dispersion is determined from the data themselves, simultaneously with the cosmological parameters. This contrasts with the strategies used to date. The advantages of the presented analysis are that it is done in a single fit (it is not iterative), it provides a statistically founded and unbiased estimate of the intrinsic dispersion, and its cosmological-parameter uncertainties account for the intrinsic dispersion uncertainty. Applied to Type Ia supernovae, my strategy provides a statistical measure to test for sub-types and assess the significance of any magnitude corrections applied to the calibrated candle. Parameter bias and differences between likelihood distributions produced by the presented and currently-used fitters are negligibly small for existing and projected supernova data sets.

Kim, Alex G

2010-12-10T23:59:59.000Z

285

A Precision Photometric Comparison between SDSS-II and CSP Type Ia Supernova Data  

E-Print Network [OSTI]

Consistency between Carnegie Supernova Project (CSP) and SDSS-II supernova (SN) survey ugri measurements has been evaluated by comparing SDSS and CSP photometry for nine spectroscopically confirmed Type Ia supernova observed contemporaneously by both programs. The CSP data were transformed into the SDSS photometric system. Sources of systematic uncertainty have been identified, quantified, and shown to be at or below the 0.023 magnitude level in all bands. When all photometry for a given band is combined, we find average magnitude differences of equal to or less than 0.011 magnitudes in ugri, with rms scatter ranging from 0.043 to 0.077 magnitudes. The u band agreement is promising, with the caveat that only four of the nine supernovae are well-observed in u and these four exhibit an 0.038 magnitude supernova-to-supernova scatter in this filter.

Mosher, J; Corlies, L; Folatelli, G; Frieman, J; Holtzman, J; Jha, S W; Kessler, R; Marriner, J; Phillips, M M; Stritzinger, M; Morrell, N; Schneider, D P

2012-01-01T23:59:59.000Z

286

Small-scale Interaction of Turbulence with Thermonuclear Flames in Type Ia Supernovae  

E-Print Network [OSTI]

Microscopic turbulence-flame interactions of thermonuclear fusion flames occuring in Type Ia Supernovae were studied by means of incompressible direct numerical simulations with a highly simplified flame description. The flame is treated as a single diffusive scalar field with a nonlinear source term. It is characterized by its Prandtl number, Pr << 1, and laminar flame speed, S_L. We find that if S_L ~ u', where u' is the rms amplitude of turbulent velocity fluctuations, the local flame propagation speed does not significantly deviate from S_L even in the presence of velocity fluctuations on scales below the laminar flame thickness. This result is interpreted in the context of subgrid-scale modeling of supernova explosions and the mechanism for deflagration-detonation-transitions.

J. C. Niemeyer; W. K. Bushe; G. R. Ruetsch

1999-05-07T23:59:59.000Z

287

Measurements of the Rate of Type Ia Supernovae at Redshift z < ~0.3 from the SDSS-II Supernova Survey  

SciTech Connect (OSTI)

We present a measurement of the volumetric Type Ia supernova (SN Ia) rate based on data from the Sloan Digital Sky Survey II (SDSS-II) Supernova Survey. The adopted sample of supernovae (SNe) includes 516 SNe Ia at redshift z {approx}< 0.3, of which 270 (52%) are spectroscopically identified as SNe Ia. The remaining 246 SNe Ia were identified through their light curves; 113 of these objects have spectroscopic redshifts from spectra of their host galaxy, and 133 have photometric redshifts estimated from the SN light curves. Based on consideration of 87 spectroscopically confirmed non-Ia SNe discovered by the SDSS-II SN Survey, we estimate that 2.04{sub -0.95}{sup +1.61}% of the photometric SNe Ia may be misidentified. The sample of SNe Ia used in this measurement represents an order of magnitude increase in the statistics for SN Ia rate measurements in the redshift range covered by the SDSS-II Supernova Survey. If we assume a SN Ia rate that is constant at low redshift (z < 0.15), then the SN observations can be used to infer a value of the SN rate of r{sub V} = (2.69{sub -0.30-0.01}{sup +0.34+0.21}) x 10{sup -5} SNe yr{sup -1} Mpc{sup -3} (H{sub 0}/(70 km s{sup -1} Mpc{sup -1})){sup 3} at a mean redshift of {approx} 0.12, based on 79 SNe Ia of which 72 are spectroscopically confirmed. However, the large sample of SNe Ia included in this study allows us to place constraints on the redshift dependence of the SN Ia rate based on the SDSS-II Supernova Survey data alone. Fitting a power-law model of the SN rate evolution, r{sub V} (z) = A{sub p} x ((1+z)/(1+z{sub 0})){sup {nu}}, over the redshift range 0.0 < z < 0.3 with z{sub 0} = 0.21, results in A{sub p} = (3.43{sub -0.15}{sup +0.15}) x 10{sup -5} SNe yr{sup -1} Mpc{sup -3} (H{sub 0}/(70 km s{sup -1} Mpc{sup -1})){sup 3} and {nu} = 2.04{sub -0.89}{sup +0.90}.

Dilday, Benjamin; /Rutgers U., Piscataway /Chicago U. /KICP, Chicago; Smith, Mathew; /Cape Town U., Dept. Math. /Portsmouth U.; Bassett, Bruce; /Cape Town U., Dept. Math. /South African Astron. Observ.; Becker, Andrew; /Washington U., Seattle, Astron. Dept.; Bender, Ralf; /Munich, Tech. U. /Munich U. Observ.; Castander, Francisco; /Barcelona, IEEC; Cinabro, David; /Wayne State U.; Filippenko, Alexei V.; /UC, Berkeley; Frieman, Joshua A.; /Chicago U. /Fermilab; Galbany, Lluis; /Barcelona, IFAE; Garnavich, Peter M.; /Notre Dame U. /Stockholm U., OKC /Stockholm U.

2010-01-01T23:59:59.000Z

288

Corrosion Behavior of Solution-Annealed CoCrMo Medical Implant  

E-Print Network [OSTI]

! ! ! Corrosion Behavior of Solution- Annealed CoCrMo Medical Implant Alloys Pooja Panigrahi University June 6, 2011 #12;! ! ""! Corrosion Behavior of Solution-Annealed CoCrMo Medical Implant Alloys and Applied Sciences Northwestern University June 6, 2011 Abstract Corrosion behavior of solution annealed

Shull, Kenneth R.

289

Posting type Advisory Subject Shifts in Mo-anode XRF element calibration factors  

E-Print Network [OSTI]

Posting type Advisory Subject Shifts in Mo-anode XRF element calibration factors Module/Species A@crocker.ucdavis.edu Supporting information A molybdenum-anode XRF instrument is used to analyze the heavier elements (Ni, Cu, Zn with lighter deposits were acquired and used in the Mo-anode XRF system. The new calibration foils resulted

Fischer, Emily V.

290

Kinetic, Mechanistic, and Spectroscopic Studies of the Mo/Cu Containing CO dehydrogenase of Oligotropha carboxidovorans  

E-Print Network [OSTI]

et. al. where active site models [Tp iPr MoO(OAr)(?-S)Cu(triazacyclononane) (Tp iPr ) = hydrotris(3-isopropylpyrazol-of CO dehydrogenase: [Tp iPr Mo (V) (O)(OAr)(?-S)Cu (I) (Me

Wilcoxen, Jarett Michael

2013-01-01T23:59:59.000Z

291

Ligand Conjugation of Chemically Exfoliated MoS2 Stanley S. Chou,+  

E-Print Network [OSTI]

Ligand Conjugation of Chemically Exfoliated MoS2 Stanley S. Chou,+ Mrinmoy De,+ Jaemyung Kim,+ Segi and chemical properties. Here, we demonstrate ligand conjugation of chemically exfoliated MoS2 using thiol-nitrilotriacetic acid chelation.13 However, colloidal sur- face modification of water dispersible, chemically exfoliated

Huang, Jiaxing

292

MoIAC Pre-Audit Form Ways to submit this form  

E-Print Network [OSTI]

information: #12;MoIAC Pre-Audit Form Major Energy Consuming Equipment: Please provide informationMoIAC Pre-Audit Form Ways to submit this form: 1. Fill up the form and fax it to 573-882-2693 Attn: Dr. Bin Wu 2. Print and return this form by mail to: Dr. Bin Wu University of Missouri

Noble, James S.

293

Stability of Graphene doping with MoO_3 and I_2  

E-Print Network [OSTI]

We dope graphene by evaporation of MoO_3 or by solution-deposition of I_2 and assess the doping stability for its use as transparent electrodes. Electrical measurements show that both dopants increase the graphene sheet conductivity and find that Mo...

D’Arsié, Lorenzo; Esconjauregui, Santiago; Weatherup, Robert; Guo, Yuzheng; Bhardwaj, Sunil; Centeno, Alba; Zurutuza, Amaia; Cepek, Cinzia; Robertson, John

2014-09-08T23:59:59.000Z

294

Student Financial Aid 11 Jesse Hall University of Missouri Columbia Columbia, MO 65211-1600  

E-Print Network [OSTI]

Student Financial Aid 11 Jesse Hall University of Missouri ­ Columbia Columbia, MO 65211-1600 PHONE;Student Financial Aid 11 Jesse Hall University of Missouri ­ Columbia Columbia, MO 65211-1600 PHONE (573 ________________________________________________________________________________________________________________________ Name of Host Institution (College or University you will be attending or taking additional classes

Taylor, Jerry

295

Sensitivity study of explosive nucleosynthesis in Type Ia supernovae: I. Modification of individual thermonuclear reaction rates  

E-Print Network [OSTI]

We explore the sensitivity of the nucleosynthesis due to type Ia supernovae with respect to uncertainties in nuclear reaction rates. We have adopted a standard one-dimensional delayed detonation model of the explosion of a Chandrasekhar-mass white dwarf, and have post-processed the thermodynamic trajectories of every mass-shell with a nucleosynthetic code, with increases (decreases) by a factor of ten on the rates of 1196 nuclear reactions. We have computed as well hydrodynamic models for different rates of the fusion reactions of 12C and of 16O. For selected reactions, we have recomputed the nucleosynthesis with alternative prescriptions for their rates taken from the JINA REACLIB database, and have analyzed the temperature ranges where modifications of their rates have the strongest effect on nucleosynthesis. The nucleosynthesis resulting from the Type Ia supernova models is quite robust with respect to variations of nuclear reaction rates, with the exception of the reaction of fusion of 12C nuclei. The energy of the explosion changes by less than \\sim4%. The changes in the nucleosynthesis due to the modification of the rates of fusion reactions are as well quite modest, for instance no species with a mass fraction larger than 0.02 experiences a variation of its yield larger than a factor of two. We provide the sensitivity of the yields of the most abundant species with respect to the rates of the most intense reactions with protons, neutrons, and alphas. In general, the yields of Fe-group nuclei are more robust than the yields of intermediate-mass elements. Among the charged particle reactions, the most influential on supernova nucleosynthesis are 30Si + p \\rightleftarrows 31P + {\\gamma}, 20Ne + {\\alpha} \\rightleftarrows 24Mg + {\\gamma}, and 24Mg + {\\alpha} \\rightleftarrows 27Al + p. The temperatures at which a modification of their rate has a larger impact are in the range 2 < T < 4 GK. (abridged)

Eduardo Bravo; Gabriel Martínez-Pinedo

2012-04-09T23:59:59.000Z

296

Incompatibility of a comoving Ly-alpha forest with supernova-Ia luminosity distances  

E-Print Network [OSTI]

Recently Perlmutter et al. suggested a positive value of Einstein's cosmological constant Lambda on the basis of luminosity distances from type-Ia supernovae. However, Lambda world models had earlier been proposed by Hoell & Priester and Liebscher et al. on the basis of quasar absorption-line data. Employing more general repulsive fluids ("dark energy") encompassing the Lambda component we quantitatively compare both approaches with each other. Fitting the SN-data by a minimum-component model consisting of dark energy + dust yields a closed universe with a large amount of dust exceeding the baryonic content constrained by big-bang nucleosynthesis. The nature of the dark energy is hardly constrained. Only when enforcing a flat universe there is a clear tendency to a dark-energy Lambda fluid and the `canonical' value Omega_M = 0.3 for dust. Conversely, fitting the quasar-data by a minimum-component model yields a sharply defined, slightly closed model with a low dust density ruling out significant pressureless dark matter. The dark-energy component obtains an equation-of-state P = -0.96 epsilon close to that of a Lambda-fluid. Omega_M = 0.3 or a precisely flat spatial geometry are inconsistent with minimum-component models. It is found that quasar and supernova data sets cannot be reconciled with each other via (repulsive ideal fluid+dust+radiation)-world models. Compatibility could be reached by drastic expansion of the parameter space with at least two exotic fluids added to dust and radiation as world constituents. If considering such solutions as far-fetched one has to conclude that the quasar absorption line and the SN-Ia constraints are incompatible.

Jens Thomas; Hartmut Schulz

2001-03-18T23:59:59.000Z

297

DUST IN A TYPE Ia SUPERNOVA PROGENITOR: SPITZER SPECTROSCOPY OF KEPLER'S SUPERNOVA REMNANT  

SciTech Connect (OSTI)

Characterization of the relatively poorly understood progenitor systems of Type Ia supernovae is of great importance in astrophysics, particularly given the important cosmological role that these supernovae play. Kepler's supernova remnant, the result of a Type Ia supernova, shows evidence for an interaction with a dense circumstellar medium (CSM), suggesting a single-degenerate progenitor system. We present 7.5-38 {mu}m infrared (IR) spectra of the remnant, obtained with the Spitzer Space Telescope, dominated by emission from warm dust. Broad spectral features at 10 and 18 {mu}m, consistent with various silicate particles, are seen throughout. These silicates were likely formed in the stellar outflow from the progenitor system during the asymptotic giant branch stage of evolution, and imply an oxygen-rich chemistry. In addition to silicate dust, a second component, possibly carbonaceous dust, is necessary to account for the short-wavelength Infrared Spectrograph and Infrared Array Camera data. This could imply a mixed chemistry in the atmosphere of the progenitor system. However, non-spherical metallic iron inclusions within silicate grains provide an alternative solution. Models of collisionally heated dust emission from fast shocks (>1000 km s{sup -1}) propagating into the CSM can reproduce the majority of the emission associated with non-radiative filaments, where dust temperatures are {approx}80-100 K, but fail to account for the highest temperatures detected, in excess of 150 K. We find that slower shocks (a few hundred km s{sup -1}) into moderate density material (n{sub 0} {approx} 50-250 cm{sup -3}) are the only viable source of heating for this hottest dust. We confirm the finding of an overall density gradient, with densities in the north being an order of magnitude greater than those in the south.

Williams, Brian J.; Borkowski, Kazimierz J.; Reynolds, Stephen P. [Physics Department, North Carolina State University, Raleigh, NC 27695-8202 (United States); Ghavamian, Parviz [Department of Physics, Astronomy, and Geosciences, Towson University, Towson, MD 21252 (United States); Blair, William P. [Department of Physics and Astronomy, Johns Hopkins University, 3400 N. Charles St., Baltimore, MD 21218-2686 (United States); Long, Knox S. [STScI, 3700 San Martin Dr., Baltimore, MD 21218 (United States); Sankrit, Ravi, E-mail: brian.j.williams@nasa.gov [SOFIA/USRA, NASA Ames Research Center, M/S N211-3, Moffett Field, CA 94035 (United States)

2012-08-10T23:59:59.000Z

298

Evaluation of sintering effects on SiC incorporated UO2 kernels under Ar and Ar-4%H2 environments  

SciTech Connect (OSTI)

Silicon carbide (SiC) is suggested as an oxygen getter in UO2 kernels used for TRISO particle fuels to lower oxygen potential and prevent kernel migration during irradiation. Scanning electron microscopy and X-ray diffractometry analyses performed on sintered kernels verified that internal gelation process can be used to incorporate SiC in urania fuel kernels. Sintering in either Ar or Ar-4%H2 at 1500 C lowered the SiC content in the UO2 kernels to some extent. Formation of UC was observed as the major chemical phase in the process, while other minor phases such as U3Si2C2, USi2, U3Si2, and UC2 were also identified. UC formation was presumed to be occurred by two reactions. The first was the SiC reaction with its protective SiO2 oxide layer on SiC grains to produce volatile SiO and free carbon that subsequently reacted with UO2 to form UC. The second process was direct UO2 reaction with SiC grains to form SiO, CO, and UC, especially in Ar-4%H2. A slightly higher density and UC content was observed in the sample sintered in Ar-4%H2, but the use of both atmospheres produced kernels with ~95% of theoretical density. It is suggested that incorporating CO in the sintering gas would prevent UC formation and preserve the initial SiC content.

Silva, Chinthaka M [ORNL] [ORNL; Lindemer, Terrence [Harbach Engineering and Solutions] [Harbach Engineering and Solutions; Hunt, Rodney Dale [ORNL] [ORNL; Collins, Jack Lee [ORNL] [ORNL; Terrani, Kurt A [ORNL] [ORNL; Snead, Lance Lewis [ORNL] [ORNL

2013-01-01T23:59:59.000Z

299

EVOLUTION OF POST-IMPACT REMNANT HELIUM STARS IN TYPE Ia SUPERNOVA REMNANTS WITHIN THE SINGLE-DEGENERATE SCENARIO  

SciTech Connect (OSTI)

The progenitor systems of Type Ia supernovae (SNe Ia) are still under debate. Based on recent hydrodynamics simulations, non-degenerate companions in the single-degenerate scenario (SDS) should survive the supernova (SN) impact. One way to distinguish between the SDS and the double-degenerate scenario is to search for the post-impact remnant stars (PIRSs) in SN Ia remnants. Using a technique that combines multi-dimensional hydrodynamics simulations with one-dimensional stellar evolution simulations, we have examined the post-impact evolution of helium-rich binary companions in the SDS. It is found that these helium-rich PIRSs (He PIRSs) dramatically expand and evolve to a luminous phase (L {approx} 10{sup 4} L{sub Sun }) about 10 yr after an SN explosion. Subsequently, they contract and evolve to become hot blue-subdwarf-like (sdO-like) stars by releasing gravitational energy, persisting as sdO-like stars for several million years before evolving to the helium red-giant phase. We therefore predict that a luminous OB-like star should be detectable within {approx}30 yr after the SN explosion. Thereafter, it will shrink and become an sdO-like star in the central regions of SN Ia remnants within star-forming regions for SN Ia progenitors evolved via the helium-star channel in the SDS. These He PIRSs are predicted to be rapidly rotating (v{sub rot} {approx}> 50 km s{sup -1}) and to have high spatial velocities (v{sub linear} {approx}> 500 km s{sup -1}). Furthermore, if SN remnants have diffused away and are not recognizable at a later stage, He PIRSs could be an additional source of single sdO stars and/or hypervelocity stars.

Pan, Kuo-Chuan; Ricker, Paul M. [Department of Astronomy, University of Illinois at Urbana-Champaign, 1002 West Green Street, Urbana, IL 61801 (United States); Taam, Ronald E., E-mail: kpan2@illinois.edu, E-mail: pmricker@illinois.edu, E-mail: r-taam@northwestern.edu [Department of Physics and Astronomy, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208 (United States)

2013-08-10T23:59:59.000Z

300

HELIUM-IGNITED VIOLENT MERGERS AS A UNIFIED MODEL FOR NORMAL AND RAPIDLY DECLINING TYPE Ia SUPERNOVAE  

SciTech Connect (OSTI)

The progenitors of Type Ia supernovae (SNe Ia) are still unknown, despite significant progress during the past several years in theory and observations. Violent mergers of two carbon-oxygen (CO) white dwarfs (WDs) are a candidate scenario suggested to be responsible for at least a significant fraction of normal SNe Ia. Here, we simulate the merger of two CO WDs using a moving-mesh code that allows for the inclusion of thin helium (He) shells (0.01 M{sub Sun }) on top of the WDs at an unprecedented numerical resolution. The accretion of He onto the primary WD leads to the formation of a detonation in its He shell. This detonation propagates around the CO WD and sends a converging shock wave into its core, known to robustly trigger a second detonation, as in the well-known double-detonation scenario for He-accreting CO WDs. However, in contrast to that scenario where a massive He shell is required to form a detonation through thermal instability, here the He detonation is ignited dynamically. Accordingly the required He-shell mass is significantly smaller, and hence its burning products are unlikely to affect the optical display of the explosion. We show that this scenario, which works for CO primary WDs with CO- as well as He-WD companions, has the potential to explain the different brightness distributions, delay times, and relative rates of normal and fast declining SNe Ia. Finally, we discuss extensions to our unified merger model needed to obtain a comprehensive picture of the full observed diversity of SNe Ia.

Pakmor, R.; Springel, V. [Heidelberger Institut fuer Theoretische Studien, Schloss-Wolfsbrunnenweg 35, D-69118 Heidelberg (Germany); Kromer, M. [Kavli Institute for the Physics and Mathematics of the Universe, University of Tokyo, Kashiwa, Chiba 277-8583 (Japan); Taubenberger, S. [Max-Planck-Institut fuer Astrophysik, Karl-Schwarzschild-Str. 1, D-85748 Garching (Germany)

2013-06-10T23:59:59.000Z

Note: This page contains sample records for the topic "ia mo ar" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Development of LEU targets for {sup 99}Mo production and their chemical processing status 1993  

SciTech Connect (OSTI)

Most of the world`s supply of {sup 99m}{Tc} for medical purposes is currently produced from {sup 99}Mo derived from the fastening of high enriched uranium (HEU). Substitution of low enriched uranium (LEU) silicide fuel for the HEU alloy and aluminide fuels used in current target designs will allow equivalent {sup 99}Mo yields with little change in target geometries. Substitution of uranium metal for uranium oxide films in other target designs will also allow the substitution of LEU for HEU. In 1993, DOE renewed funding that was terminated in 1990 for development of LEU targets for {sup 99}Mo production. During the past year, our efforts were to (1) renew contact with {sup 99}Mo producers, (2) define the means to test our process for recovering {sup 99}Mo from irradiated LEU-silicide targets, and (3) begin to test our process on spent LEU-silicide miniplates stored at ANL from past fuel development studies.

Vandegrift, G.F.; Hutter, J.C.; Srinivasan, B.; Matos, J.E.; Snelgrove, J.L.

1993-10-01T23:59:59.000Z

302

Electrical properties of a-C:Mo films produced by dual-cathode filtered cathodic arc plasma deposition  

E-Print Network [OSTI]

and Related Materials Electrical properties of a-C:Mo filmsNo. DE-AC02-05CH11231. Electrical properties of a-C:Mo filmsair. Film resistivity and electrical activation energy were

Sansongsiri, Sakon

2008-01-01T23:59:59.000Z

303

Electronic Structure Description of the Cis-MoOS Unit in Models for Molybdenum Hydroxylases  

SciTech Connect (OSTI)

The molybdenum hydroxylases catalyze the oxidation of numerous aromatic heterocycles and simple organics and, unlike other hydroxylases, utilize water as the source of oxygen incorporated into the product. The electronic structures of the cis-MoOS units in CoCp{sub 2}[Tp{sup iPr}Mo{sup V}OS(OPh)] and Tp{sup iPr}Mo{sup VI}OS(OPh) (Tp{sup iPr} = hydrotris(3-isopropylpyrazol-1-yl)borate), new models for molybdenum hydroxylases, have been studied in detail using S K-edge X-ray absorption spectroscopy, vibrational spectroscopy, and detailed bonding calculations. The results show a highly delocalized Mo {double_bond} S {pi}* LUMO redox orbital that is formally Mo(d{sub xy}) with {approx}35% sulfido ligand character. Vibrational spectroscopy has been used to quantitate Mo-S{sub sulfido} bond order changes in the cis-MoOS units as a function of redox state. Results support a redox active molecular orbital that has a profound influence on MoOS bonding through changes to the relative electro/nucleophilicity of the terminal sulfido ligand accompanying oxidation state changes. The bonding description for these model cis-MoOS systems supports enzyme mechanisms that are under orbital control and dominantly influenced by the unique electronic structure of the cis-MoOS site. The electronic structure of the oxidized enzyme site is postulated to play a role in polarizing a substrate carbon center for nucleophilic attack by metal activated water and acting as an electron sink in the two-electron oxidation of substrates.

Doonan, C.J.; Rubie, N.D.; Peariso, K.; Harris, H.H.; Knottenbelt, S.Z.; George, G.N.; Young, C.G.; Kirk, M.L.; /New Mexico U. /Melbourne U. /SLAC, SSRL

2009-04-29T23:59:59.000Z

304

Phase transformation of ZnMoO{sub 4} by localized thermal spike  

SciTech Connect (OSTI)

We show that ZnMoO{sub 4} remains in stable phase under thermal annealing up to 1000?°C, whereas it decomposes to ZnO and MoO{sub 3} under transient thermal spike induced by 100?MeV Ag irradiation. The transformation is evidenced by X-ray diffraction (XRD), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). Thin films of ZnMoO{sub 4} were synthesized by thermal evaporation and subsequent annealing in oxygen ambient at 600?°C for 4?h. XRD results show that as the irradiation fluence increases, the peak related to ZnMoO{sub 4} decreases gradually and eventually disappear, whereas peaks related to ZnO grow steadily up to fluence of 3?×?10{sup 12} ions/cm{sup 2} and thereafter remain stable till highest fluence. This indicates that polycrystalline ZnMoO{sub 4} film has transformed to polycrystalline ZnO thin film. The Raman lines related to ZnMoO{sub 4} are observed to have disappeared with increasing irradiation fluence. XPS results show modification in bonding and depletion of Mo from near surface region after the ion irradiation. Cross-sectional transmission electron microscopy result shows the formation of ion track of diameter 12–16?nm. These results demonstrate that ion beam methods provide the means to control phase splitting of ZnMoO{sub 4} to ZnO and MoO{sub 3} within nanometric dimension along the ion track. The observation of phase splitting and Mo loss are explained in the framework of ion beam induced thermal spike formalism.

Agarwal, D. C.; Avasthi, D. K.; Kabiraj, D. [Inter-University Accelerator Center, Aruna Asaf Ali Marg, New Delhi 110067 (India); Varma, S. [Institute of Physics, Sachivalaya Marg, Bhubaneswar 751005 (India); Kremer, Felipe; Ridgway, M. C. [Australian National University, Canberra ACT 0200 (Australia)

2014-04-28T23:59:59.000Z

305

arXiv:astro-ph/0503251v213Mar2005 DRAFT VERSION MARCH 13, 2005  

E-Print Network [OSTI]

emission is due to the outflow ejected during the GF energizing a thin shell surrounding a pre 20450, MS 29, Stanford, CA 94309; granot@slac.stanford.edu 2 IAS, Einstein Drive, Princeton, NJ 08540

Taylor, Greg

306

E-Print Network 3.0 - ar isotopic chain Sample Search Results  

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

of Geological Sciences, University of Texas at Austin Collection: Geosciences 29 HYDROGEN ISOTOPE SEPARATION AT PNPI I.A. Alekseev, K.A. Konoplev, V.D. Trenin Summary: HYDROGEN...

307

Theoretical study of the interaction of Fe, Fe/sup +/, and FeCO with Ar  

SciTech Connect (OSTI)

Ab initio Hartree--Fock calculations were performed on FeAr and FeAr/sup +/ in order to determine the interaction of both neutral and singly-ionized Fe atoms trapped in Ar, and on ArFeCO and FeCOAr in order to ascertain the effect of an Ar matrix on the FeCO molecule. Quadrupole splittings and isomer shifts are computed using ab initio orbital populations and charge densities scaled by a relativistic factor. Good agreement between calculated and experimental hyperfine parameters is found in each case. The interaction energy for Fe/sup +/--Ar has been computed by ab initio Hartree--Fock and effective-core potential (ECP) methods. Both approaches yield a minimum between Fe/sup +/ and Ar at approximately 7.6 bohr.

Braga, M.; Almeida, A.L.; Taft, C.A.; Hammond, B.L.; Lester W.A. Jr.

1988-10-15T23:59:59.000Z

308

Triple photoionization of Ne and Ar near threshold  

SciTech Connect (OSTI)

The triple-photoionization cross section of neon and argon near threshold has been investigated by ion time-of-flight spectrometry. We applied the Wannier power law to our data and confirmed the theoretical Wannier exponent in the cases of Ne and Ar. Our data also agree with previous findings regarding the Wannier exponent and its range of validity for Ne. However, the Wannier power law exhibits a much smaller range of validity of 2 eV for Ar compared to 5 eV for Ne. Also, in contrast to a previous experiment, we do not find a 'second' power law but a gradual decrease of the exponent above the range of validity of the Wannier power law.

Bluett, J.B.; Wehlitz, R. [Synchrotron Radiation Center, UW-Madison, Stoughton, Wisconsin 53589 (United States); Lukic, D. [Institute of Physics, 11001 Belgrade (Serbia and Montenegro)

2004-04-01T23:59:59.000Z

309

Nome Instituio Pas E-mail Natalia Gabriela Fracassi Instituto Nacional de Tecnologia Agropecuaria Argentina natfracassi@yahoo.com.ar  

E-Print Network [OSTI]

Agropecuaria Argentina natfracassi@yahoo.com.ar Andre Alexander Held Commonwealth Scientific and Industrial

310

EVALUATING SYSTEMATIC DEPENDENCIES OF TYPE Ia SUPERNOVAE: THE INFLUENCE OF PROGENITOR {sup 22}Ne CONTENT ON DYNAMICS  

SciTech Connect (OSTI)

We present a theoretical framework for formal study of systematic effects in supernovae Type Ia (SNe Ia) that utilizes two-dimensional simulations to implement a form of the deflagration-detonation transition (DDT) explosion scenario. The framework is developed from a randomized initial condition that leads to a sample of simulated SNe Ia whose {sup 56}Ni masses have a similar average and range to those observed, and have many other modestly realistic features such as the velocity extent of intermediate-mass elements. The intended purpose is to enable statistically well defined studies of both physical and theoretical parameters of the SNe Ia explosion simulation. We present here a thorough description of the outcome of the SNe Ia explosions produced by our current simulations. A first application of this framework is utilized to study the dependence of the SNe Ia on the {sup 22}Ne content, which is known to be directly influenced by the progenitor stellar population's metallicity. Our study is very specifically tailored to measure how the {sup 22}Ne content influences the competition between the rise of plumes of burned material and the expansion of the star before these plumes reach DDT conditions. This influence arises from the dependence of the energy release, progenitor structure, and laminar flame speed on {sup 22}Ne content. For this study, we explore these three effects for a fixed carbon content and DDT density. By setting the density at which nucleosynthesis takes place during the detonation phase of the explosion, the competition between plume rise and stellar expansion controls the amount of material in nuclear statistical equilibrium (NSE) and therefore {sup 56}Ni produced. Of particular interest is how this influence of {sup 22}Ne content compares to the direct modification of the {sup 56}Ni mass via the inherent neutron excess as discussed by Timmes et al. Although the outcome following from any particular ignition condition can change dramatically with {sup 22}Ne content, with a sample of 20 ignition conditions we find that the systematic change in the expansion of the star prior to detonation is not large enough to compete with the dependence discussed by Timmes et al. In fact, our results show no statistically significant dependence of the predetonation expansion on {sup 22}Ne content, pointing to the morphology of the ignition condition as being the dominant dynamical driver of the {sup 56}Ni yield of the explosion. However, variations in the DDT density, which were specifically excluded here, are also expected to be important and to depend systematically on {sup 22}Ne content.

Townsley, Dean M. [Department of Astronomy/Steward Observatory, University of Arizona, Tucson, AZ (United States); Jackson, Aaron P.; Calder, Alan C. [Department of Physics and Astronomy, State University of New York - Stony Brook, Stony Brook, NY (United States); Chamulak, David A.; Brown, Edward F. [Department of Physics and Astronomy, Michigan State University, East Lansing, MI (United States); Timmes, F. X. [Joint Institute for Nuclear Astrophysics, Michigan State University, East Lansing, MI 48824 (United States)], E-mail: townsley@as.arizona.edu

2009-08-20T23:59:59.000Z

311

The production of /sup 38/Ar and /sup 39/Ar by 14-MeV neutrons on /sup 39/K  

SciTech Connect (OSTI)

The authors have determined the cross sections for the production of /sup 38/Ar and /sup 39/Ar from the (n,n'rho) and (n,rho) reactions by neutrons of -- 14 MeV incident on /sup 39/K. Three potassium-bearing specimens were irradiated with fluences of --10/sup 17/ neutrons, and the argon isotopes were measured by mass spectrometry. Previously reported measurements are in substantial disagreement with our results. Values from the three new measurements are consistent with each other and our computational modeling. Nevertheless, there remains an unexplained increase in the cross sections for both reactions as the neutron energy increases from --14.5 to 14.8 MeV.

Foland, K.A.; Borg, R.J.; Mustafa, M.G.

1987-02-01T23:59:59.000Z

312

Investigation of the optical properties of MoS{sub 2} thin films using spectroscopic ellipsometry  

SciTech Connect (OSTI)

Spectroscopic ellipsometry (SE) characterization of layered transition metal dichalcogenide (TMD) thin films grown by vapor phase sulfurization is reported. By developing an optical dispersion model, the extinction coefficient and refractive index, as well as the thickness of molybdenum disulfide (MoS{sub 2}) films, were extracted. In addition, the optical band gap was obtained from SE and showed a clear dependence on the MoS{sub 2} film thickness, with thinner films having a larger band gap energy. These results are consistent with theory and observations made on MoS{sub 2} flakes prepared by exfoliation, showing the viability of vapor phase derived TMDs for optical applications.

Yim, Chanyoung; O'Brien, Maria; Winters, Sinéad [School of Chemistry, Trinity College Dublin, Dublin 2 (Ireland); Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College Dublin, Dublin 2 (Ireland); McEvoy, Niall [Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College Dublin, Dublin 2 (Ireland); Mirza, Inam; Lunney, James G. [Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College Dublin, Dublin 2 (Ireland); School of Physics, Trinity College Dublin, Dublin 2 (Ireland); Duesberg, Georg S., E-mail: duesberg@tcd.ie [School of Chemistry, Trinity College Dublin, Dublin 2 (Ireland); Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College Dublin, Dublin 2 (Ireland); Advanced Materials and BioEngineering Research (AMBER) Centre, Trinity College Dublin, Dublin 2 (Ireland)

2014-03-10T23:59:59.000Z

313

sup 40 Ar/ sup 39 Ar age calibration of the litho- and paleomagnetic stratigraphies of the Ngorora Formation, Kenya  

SciTech Connect (OSTI)

Precise eruptive ages have been determined by the laser-fusion, single-crystal {sup 40}Ar/{sup 39}Ar method for juvenile volcanic feldspars from reworked and contaminated volcaniclastic rocks of the middle Miocene Ngorora Formation, Kenya Rift Valley. These ages range from 13.06 Ma at the base to 10.51 Ma toward the top of the type section near Kabarsero. Correlation of the local paleomagnetic stratigraphies with the geomagnetic reversal time scale yields magnetochronologic age estimates that are younger than the isotopic ages by an average of 0.18 Ma. Much of the discrepancy can be eliminated if an inferred change in sea-floor spreading rate occurred at 13 Ma or earlier, rather than at 10.42 Ma as previously suggested. Sedimentation rates at Kabarsero calculated from the {sup 40}Ar/{sup 39}Ar results decrease from initial values of {approximately}25 cm/1,000 yr to {approximately}5 cm/1,000 yr toward the top of the section. The initial rapid sedimentation rates characterize the first 0.1 to 0.3 m.y. following emplacement of the underlying, voluminous, basin-filling Tiim Phonolites, indicating that the Baringo Basin at this time may not have existed as a rift valley created by extensional tectonics, but instead may have been a subsidence feature formed in response to removal of large volumes of magma from the lithosphere. A premolar tentatively identified as Proconsul sp. indet. found in the Ngorora Formation near the village of Bartabwa has been dated at {approximately}12.42 Ma, representing perhaps the last known occurrence of this genus in the fossil record.

Deino, A.; Drake, R. (Institute of Human Origins, Berkeley, CA (USA)); Tauxe, L. (Scripps Institute of Oceanography, La Jolla, CA (USA)); Monaghan, M. (Univ. of Chicago, IL (USA))

1990-07-01T23:59:59.000Z

314

CP Tech Center I Iowa State University I 2711 S. Loop Dr. Suite 4700,Ames, IA 50010-8664 I 515-294-5798 FOR MORE INFORMATION  

E-Print Network [OSTI]

CP Tech Center I Iowa State University I 2711 S. Loop Dr. Suite 4700,Ames, IA 50010-8664 I 515 calcium sulfate in the form of hemihydrate (plaster) in the cement (false set) or the uncontrolled early

315

Is the central binary system of the planetary nebula Henize 2-428 a Type Ia supernova progenitor?  

E-Print Network [OSTI]

We account for recent observations of the binary system at the center of the bipolar planetary nebula Henize 2-428 by the presence of one degenerate core with a low-mass main sequence companion, rather than by two degenerate objects. We argue that the variability of the He II 5412A spectral line can be accounted for by a time-varying broad absorption line from the central star on top of which there is a time-varying narrow emission line from the compact nebula. The two (almost) symmetric broad minima in the light curve are attributed to tidal distortion caused by a companion. We find problems in the recently proposed and competing explanation of two equal-mass degenerate objects that supposedly will eventually merge, possibly leading to a SN Ia. We conclude that Henize 2-428 cannot be claimed yet to support the double-degenerate scenario for Type Ia supernovae.

Garcia-Berro, Enrique; Althaus, Leandro G

2015-01-01T23:59:59.000Z

316

Density functional theory investigation of the electronic structure and thermoelectric properties of layered MoS{sub 2}, MoSe{sub 2} and their mixed-layer compound  

SciTech Connect (OSTI)

First principles density functional theory calculations were carried out for the 2H-MoQ{sub 2} (Q=S and Se) and their hypothetical mixed-layer compound. Due to the different electronegativities of S and Se atoms on MoQ{sub 2}, the band gap size could be adjusted in mixed-layer compound MoS{sub 2}/MoSe{sub 2}. Also, the indirect band gap in pure MoQ{sub 2} compounds is changed to the pseudo direct band gap in mixed-layer MoS{sub 2}/MoSe{sub 2} which is similar to the monolayer compound. The layer mixing enhances the thermoelectric properties because of the increased density of states around the Fermi level and the decreased band gap size. Therefore, we suggest that this layer mixing approach should be regarded as a useful way to modulate their electronic structures and to improve their thermoelectric properties. -- Graphical abstract: On the basis of density functional calculations we predict that the mixed-layer compounds 2H-MoS{sub 2}/2H-MoSe{sub 2}, in which two different layers 2H-MoS{sub 2} and 2H-MoSe{sub 2}, have enhanced thermoelectric properties because of the increased density of states around the Fermi level and the decreased band gap size. Highlights: • We explored a way of improving TE properties of 2H-MoQ{sub 2} on DFT methods. • The mixed-layer compounds MoS{sub 2}/MoSe{sub 2} have enhanced thermoelectric properties. • This is caused by modulated electronic structure of mixed layer compound. • Layer mixing approach should be regarded as a useful way to improve TE properties.

Lee, Changhoon; Hong, Jisook [Department of Chemistry, Pohang University of Science and Technology, Pohang 790-784 (Korea, Republic of); Lee, Wang Ro [Faculty of Liberal Education, Chonbuk National University, Jeonju, Jeonbuk 561-756 (Korea, Republic of); Kim, Dae Yeon [Agency for Defense Development (ADD), Chinhae, Kyungnam 645-600 (Korea, Republic of); Shim, Ji Hoon, E-mail: jhshim@postech.ac.kr [Department of Chemistry, Pohang University of Science and Technology, Pohang 790-784 (Korea, Republic of); Divisions of Advanced Nuclear Engineering, Pohang University of Science and Technology, Pohang 790-784 (Korea, Republic of)

2014-03-15T23:59:59.000Z

317

THE IMPACT OF TYPE Ia SUPERNOVA EXPLOSIONS ON HELIUM COMPANIONS IN THE CHANDRASEKHAR-MASS EXPLOSION SCENARIO  

SciTech Connect (OSTI)

In the version of the single-degenerate scenario of Type Ia supernovae (SNe Ia) studied here, a carbon-oxygen white dwarf explodes close to the Chandrasekhar limit after accreting material from a non-degenerate helium (He) companion star. In the present study, we employ the STELLAR GADGET code to perform three-dimensional hydrodynamical simulations of the interaction of the SN Ia ejecta with the He companion star taking into account its orbital motion and spin. It is found that only 2%-5% of the initial companion mass is stripped off from the outer layers of He companion stars due to the supernova (SN) impact. The dependence of the unbound mass (or the kick velocity) on the orbital separation can be fitted to a good approximation by a power law for a given companion model. After the SN impact, the outer layers of a He donor star are significantly enriched with heavy elements from the low-expansion-velocity tail of SN Ia ejecta. The total mass of accumulated SN-ejecta material on the companion surface reaches about {approx}> 10{sup -3} M{sub Sun} for different companion models. This enrichment with heavy elements provides a potential way to observationally identify the surviving companion star in SN remnants. Finally, by artificially adjusting the explosion energy of the W7 explosion model, we find that the total accumulation of SN ejecta on the companion surface is also dependent on the explosion energy with a power-law relation to a good approximation.

Liu Zhengwei; Wang, B.; Han, Z. W. [Yunnan Observatories, Chinese Academy of Sciences, Kunming 650011 (China); Pakmor, R. [Heidelberger Institut fuer Theoretische Studien, Schloss-Wolfsbrunnenweg 35, D-69118 Heidelberg (Germany); Seitenzahl, I. R.; Hillebrandt, W.; Kromer, M.; Edelmann, P.; Taubenberger, S. [Max-Planck-Institut fuer Astrophysik, Karl-Schwarzschild-Str. 1, D-85741 Garching (Germany); Roepke, F. K. [Institut fuer Theoretische Physik und Astrophysik, Universitaet Wuerzburg, Am Hubland, D-97074 Wuerzburg (Germany); Maeda, K., E-mail: zwliu@ynao.ac.cn [Kavli Institute for the Physics and Mathematics of the Universe (Kavli-IPMU), Todai Institutes for Advanced Study (TODIAS), University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8583 (Japan)

2013-09-01T23:59:59.000Z

318

Role of Penning ionization in the enhancement of streamer channel conductivity and Ar(1s{sub 5}) production in a He-Ar plasma jet  

SciTech Connect (OSTI)

Plasma jet devices that use a helium gas flow mixed with a small percentage of argon have been shown to operate with a larger discharge current and enhanced production of the Ar(1s{sub 5}) metastable state, particularly in the discharge afterglow. In this experiment, time-resolved quantitative measurements of He(2{sup 3}S{sub 1}) and Ar(1s{sub 5}) metastable species were combined with current and spectrally resolved emission measurements to elucidate the role of Penning ionization in a helium plasma jet with a variable argon admixture. The plasma jet was enclosed in a glass chamber through which a flowing nitrogen background was maintained at 600 Torr. At 3%-5% Ar admixture, we observed a {approx}50% increase in the peak circuit current and streamer velocity relative to a pure helium plasma jet for the same applied voltage. The streamer initiation delay also decreased by {approx}20%. Penning ionization of ground-state argon was found to be the dominant quenching pathway for He(2{sup 3}S{sub 1}) up to 2% Ar and was directly correlated with a sharp increase in both the circuit current and afterglow production of Ar(1s{sub 5}) for Ar admixtures up to 1%, but not necessarily with the streamer velocity, which increased more gradually with Ar concentration. Ar(1s{sub 5}) was produced in the afterglow through recombination of Ar{sup +} and dissociative recombination of Ar{sub 2}{sup +} as the local mean electron energy decreased in the plasma channel behind the streamer head. The discharge current and argon metastable enhancement are contingent on the rapid production of He(2{sup 3}S{sub 1}) near the streamer head, >5 Multiplication-Sign 10{sup 12} cm{sup -3} in 30 ns under the conditions of this experiment.

Sands, Brian L. [UES, Inc., 4401 Dayton-Xenia Rd., Dayton, Ohio 45432 (United States); Huang, Shih K.; Speltz, Jared W.; Niekamp, Matthew A. [Department of Mechanical and Materials Engineering, Wright State University, 3640 Colonel Glenn Hwy., Dayton, Ohio 45435 (United States); Ganguly, Biswa N. [Air Force Research Laboratory, 1950 5th St. Wright Patterson Air Force Base, Ohio 45433 (United States)

2013-04-21T23:59:59.000Z

319

High damage-resistant Mo mirror for high-power TEA CO/sub 2/ laser systems  

SciTech Connect (OSTI)

A high-purity molybdenum (Mo) mirror was developed by an electron-beam melting method (e.b.m. Mo mirror). For high-power TEA CO/sub 2/ laser, the e.b.m. Mo mirror has two to four times higher surface damage threshold than that of an Au-coated glass mirror and three times longer lifetime than that of a powder metallurgy Mo mirror (p.m. Mo mirror) when laser energy density lower than 60 J/cm/sup 2/ was irradiated with a 0.5-pps repetition rate. It was found that the difference between the e.b.m. Mo mirror and the p.m. Mo mirror at the laser-damage threshold was due to the five surface without voids and the small amount of impurities.

Ichikawa, Y.; Yoshida, K.; Tsunawaki, Y.; Yamanaka, M.; Yamanaka, T.; Yamanaka, C.; Okamoto, H.; Matsusue, N.; Kitajima, K.

1987-09-01T23:59:59.000Z

320

SPECTROSCOPIC OBSERVATIONS OF SN 2012fr: A LUMINOUS, NORMAL TYPE Ia SUPERNOVA WITH EARLY HIGH-VELOCITY FEATURES AND A LATE VELOCITY PLATEAU  

SciTech Connect (OSTI)

We present 65 optical spectra of the Type Ia SN 2012fr, 33 of which were obtained before maximum light. At early times, SN 2012fr shows clear evidence of a high-velocity feature (HVF) in the Si II {lambda}6355 line that can be cleanly decoupled from the lower velocity ''photospheric'' component. This Si II {lambda}6355 HVF fades by phase -5; subsequently, the photospheric component exhibits a very narrow velocity width and remains at a nearly constant velocity of {approx}12,000 km s{sup -1} until at least five weeks after maximum brightness. The Ca II infrared triplet exhibits similar evidence for both a photospheric component at v Almost-Equal-To 12,000 km s{sup -1} with narrow line width and long velocity plateau, as well as an HVF beginning at v Almost-Equal-To 31,000 km s{sup -1} two weeks before maximum. SN 2012fr resides on the border between the ''shallow silicon'' and ''core-normal'' subclasses in the Branch et al. classification scheme, and on the border between normal and high-velocity Type Ia supernovae (SNe Ia) in the Wang et al. system. Though it is a clear member of the ''low velocity gradient'' group of SNe Ia and exhibits a very slow light-curve decline, it shows key dissimilarities with the overluminous SN 1991T or SN 1999aa subclasses of SNe Ia. SN 2012fr represents a well-observed SN Ia at the luminous end of the normal SN Ia distribution and a key transitional event between nominal spectroscopic subclasses of SNe Ia.

Childress, M. J.; Scalzo, R. A.; Sim, S. A.; Tucker, B. E.; Yuan, F.; Schmidt, B. P. [Research School of Astronomy and Astrophysics, Australian National University, Canberra, ACT 2611 (Australia); Cenko, S. B.; Filippenko, A. V. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Silverman, J. M. [Department of Astronomy, University of Texas, Austin, TX 78712-0259 (United States); Contreras, C.; Hsiao, E. Y.; Phillips, M.; Morrell, N. [Las Campanas Observatory, Carnegie Observatories, Casilla 601, La Serena (Chile); Jha, S. W.; McCully, C. [Department of Physics and Astronomy, Rutgers, State University of New Jersey, 136 Frelinghuysen Road, Piscataway, NJ 08854 (United States); Anderson, J. P.; De Jaeger, T.; Forster, F. [Departamento de Astronomia, Universidad de Chile, Casilla 36-D, Santiago (Chile); Benetti, S. [INAF Osservatorio Astronomico di Padova, Vicolo dell'Osservatorio 5, I-35122 Padova (Italy); Bufano, F., E-mail: mjc@mso.anu.edu.au [Departamento de Ciencias Fisicas, Universidad Andres Bello, Avda. Republica 252, Santiago (Chile); and others

2013-06-10T23:59:59.000Z

Note: This page contains sample records for the topic "ia mo ar" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Aboveground test of an advanced Li$_2$MoO$_4$ scintillating bolometer to search for neutrinoless double beta decay of $^{100}$Mo  

E-Print Network [OSTI]

Large lithium molybdate (Li$_2$MoO$_4$) crystal boules were produced by using the low thermal gradient Czochralski growth technique from deeply purified molybdenum. A small sample from one of the boules was preliminary characterized in terms of X-ray-induced and thermally-excited luminescence. A large cylindrical crystalline element (with a size of $\\oslash 40\\times40$ mm) was used to fabricate a scintillating bolometer, which was operated aboveground at $\\sim 15$ mK by using a pulse-tube cryostat housing a high-power dilution refrigerator. The excellent detector performance in terms of energy resolution and $\\alpha$ background suppression along with preliminary positive indications on the radiopurity of this material show the potentiality of Li$_2$MoO$_4$ scintillating bolometers for low-counting experiment to search for neutrinoless double beta decay of $^{100}$Mo.

T. B. Bekker; N. Coron; F. A. Danevich; V. Ya. Degoda; A. Giuliani; V. D. Grigorieva; N. V. Ivannikova; M. Mancuso; P. de Marcillac; I. M. Moroz; C. Nones; E. Olivieri; G. Pessina; D. V. Poda; V. N. Shlegel; V. I. Tretyak; M. Velazquez

2014-12-17T23:59:59.000Z

322

Aboveground test of an advanced Li$_2$MoO$_4$ scintillating bolometer to search for neutrinoless double beta decay of $^{100}$Mo  

E-Print Network [OSTI]

Large lithium molybdate (Li$_2$MoO$_4$) crystal boules were produced by using the low thermal gradient Czochralski growth technique from deeply purified molybdenum. A small sample from one of the boules was preliminary characterized in terms of X-ray-induced and thermally-excited luminescence. A large cylindrical crystalline element (with a size of $\\oslash 40\\times40$ mm) was used to fabricate a scintillating bolometer, which was operated aboveground at $\\sim 15$ mK by using a pulse-tube cryostat housing a high-power dilution refrigerator. The excellent detector performance in terms of energy resolution and $\\alpha$ background suppression along with preliminary positive indications on the radiopurity of this material show the potentiality of Li$_2$MoO$_4$ scintillating bolometers for low-counting experiment to search for neutrinoless double beta decay of $^{100}$Mo.

Bekker, T B; Danevich, F A; Degoda, V Ya; Giuliani, A; Grigorieva, V D; Ivannikova, N V; Mancuso, M; de Marcillac, P; Moroz, I M; Nones, C; Olivieri, E; Pessina, G; Poda, D V; Shlegel, V N; Tretyak, V I; Velazquez, M

2014-01-01T23:59:59.000Z

323

First bolometric measurement of the two neutrino double beta decay of $^{100}$Mo with a ZnMoO$_4$ crystals array  

E-Print Network [OSTI]

The large statistics collected during the operation of a ZnMoO$_4$ array, for a total exposure of 1.3 kg $\\cdot$ day of $^{100}$Mo, allowed the first bolometric observation of the two neutrino double beta decay of $^{100}$Mo. The observed spectrum of each crystal was reconstructed taking into account the different background contributions due to environmental radioactivity and internal contamination. The analysis of coincidences between the crystals allowed the assignment of constraints to the intensity of the different background sources, resulting in a reconstruction of the measured spectrum down to an energy of $\\sim$300 keV. The half-life extracted from the data is T$_{1/2}^{2\

L. Cardani; L. Gironi; N. Ferreiro Iachellini; L. Pattavina; J. W. Beeman; F. Bellini; N. Casali; O. Cremonesi; I. Dafinei; S. Di Domizio; F. Ferroni; E. Galashov; C. Gotti; S. Nagorny; F. Orio; G. Pessina; G. Piperno; S. Pirro; E. Previtali; C. Rusconi; C. Tomei; M. Vignati

2014-04-30T23:59:59.000Z

324

Precipitation behavior of Ni-Cr-22 Fe-18 Mo (Hastelloy-X) and Ni-Cr-22 Co-12 Mo (Inconel-617) after isothermal aging  

SciTech Connect (OSTI)

The precipitation behavior of the nickel-base alloys Ni-Cr-22Fe-18Mo (Hastelloy-X) and Ni-Cr-22Co12Mo (Inconel-617) has been investigated as a function of aging temperature. Hastelloy-X shows that M/sub 6/C and TiN are primary precipitates and M/sub 12/C, A/sub 3/B/sub 2/ (approx. = Fe/sub 3/Mo/sub 2/), and M/sub 23/C/sub 6/ are secondary precipitates, while Inconel-617 also has M/sub 6/C and TiN as primary precipitates and M/sub 23/C/sub 6/, M/sub 12/C, and Ni/sub 3/AlTi as secondary precipitates. The characterization has been carried out by metallographic and transmission electron microscopy investigations and by x-ray examinations of electrochemical isolated precipitates.

Kirchhofer, H.; Nickel, H.; Schubert, F.

1984-07-01T23:59:59.000Z

325

Electrochemical Testing of Ni-Cr-Mo-Gd Alloys  

SciTech Connect (OSTI)

The waste package site recommendation design specified a boron-containing stainless steel, Neutronit 976/978, for fabrication of the internal baskets that will be used as a corrosion-resistant neutron-absorbing material. Recent corrosion test results gave higher-than-expected corrosion rates for this material. The material callout for these components has been changed to a Ni-Cr-Mo-Gd alloy (ASTM-B 932-04, UNS N06464) that is being developed at the Idaho National Laboratory. This report discusses the results of initial corrosion testing of this material in simulated in-package environments that could contact the fuel baskets after breach of the waste package outer barrier. The corrosion test matrix was executed using the potentiodynamic and potentiostatic electrochemical test techniques. The alloy performance shows low rates of general corrosion after initial removal of a gadolinium-rich second phase that intersects the surface. The high halide-containing test solutions exhibited greater tendencies toward initiation of crevice corrosion.

T. E. Lister; R. E. Mizia; H. Tian

2005-10-01T23:59:59.000Z

326

The Joint Efficient Dark-energy Investigation (JEDI): Measuring the cosmic expansion history from type Ia supernovae  

E-Print Network [OSTI]

JEDI (Joint Efficient Dark-energy Investigation) is a candidate implementation of the NASA-DOE Joint Dark Energy Mission (JDEM). JEDI will probe dark energy in three independent methods: (1) type Ia supernovae, (2) baryon acoustic oscillations, and (3) weak gravitational lensing. In an accompanying paper, an overall summary of the JEDI mission is given. In this paper, we present further details of the supernova component of JEDI. To derive model-independent constraints on dark energy, it is important to precisely measure the cosmic expansion history, H(z), in continuous redshift bins from z \\~ 0-2 (the redshift range in which dark energy is important). SNe Ia at z > 1 are not readily accessible from the ground because the bulk of their light has shifted into the near-infrared where the sky background is overwhelming; hence a space mission is required to probe dark energy using SNe. Because of its unique near-infrared wavelength coverage (0.8-4.2 microns), JEDI has the advantage of observing SNe Ia in the rest frame J band for the entire redshift range of 0 energy are discussed, with special emphasis on the improved precision afforded by the rest frame near-infrared data.

M. M. Phillips; Peter Garnavich; Yun Wang; David Branch; Edward Baron; Arlin Crotts; J. Craig Wheeler; Edward Cheng; Mario Hamuy; for the JEDI Team

2006-06-28T23:59:59.000Z

327

Chameleon-like cosmology in light of SNeIa, CMB, BAO and OHD observational data sets  

E-Print Network [OSTI]

During this work an interacting chameleon-like scalar field scenario, by considering SNeIa, CMB, BAO and OHD data sets is investigated. Some cosmological parameters includes of Hubble, deceleration and coincidence parameters in such mechanism are analysed. It is realized for estimation the free parameters of a theoretical model, it is better all mentioned observational data sets be considered. In fact if one considers SNeIa, CMB and BAO but ignores OHD it maybe leads to an incorrect result. Also it will find out, when we margin the free parameters, the $\\chi _{\\rm{T}}^2$ function should be re-weighted, this fact arises from the abundance of SNeIa and OHD sources in comparison to CMB and BAO data sets. We margin the likelihood $\\mathcal{L} (\\Omega_{\\rm{m0}} ,\\omega_1 , \\beta)$ with respect to $\\omega_1$, $\\beta$ and $\\Omega_{\\rm{m0}}$ respectively and by means of two dimensional confidence levels $68.3\\%$, $90\\%$ and $95.4\\%$, the relative probability functions are plotted. Also the quantities which maximize t...

Rabiei, Sayed Wrya; Saaidi, Khaled; Aghamohammadi, Ali

2015-01-01T23:59:59.000Z

328

Explosion Models for Type Ia Supernovae: A Comparison with Observed Light Curves, distances, H_o and q_o  

E-Print Network [OSTI]

Theoretical monochromatic light curves and photospheric expansion velocities are compared with observations of 27 Type Ia supernovae (SNe Ia). A set of 37 models has been considered which encompasses all currently discussed explosion scenarios for Type Ia supernovae including deflagrations, detonations, delayed detonations, pulsating delayed detonations and tamped detonations of Chandra- mass, and Helium detonations of low mass white dwarfs. The explosions are calculated using one-dimensional Lagrangian hydro and radiation-hydro codes with incorporated nuclear networks. Subsequently, light curves are constructed using our LC scheme which includes an implicit radiation transport, expansion opacities, a Monte-Carlo $\\gamma $-ray transport, and molecular and dust formation. For some supernovae, results of detailed non-LTE calculations have been considered. Observational properties of our series of models are discussed, the relation between the absolute brightness, post-maximum decline rates, the colors at several moments of time, etc. All models with a Ni production larger than 0.4 solar masses produce light curves of similar brightness. The influence of the cosmological red shift on the light curves and on the correction for interstellar reddening is discussed. Based on data rectification of the standard deviation, a quantitative procedure to fit the observations has been used to the determine the free parameters, i.e. the correct model, the distance, the reddening, and the time of the explosion. The results are discussed in detail and applied to determine Ho and qo.

P. Hoeflich; A. Khokkhlov

1996-02-06T23:59:59.000Z

329

Direct numerical simulations of type Ia supernovae flames I: The landau-darrieus instability  

SciTech Connect (OSTI)

Planar flames are intrinsically unstable in open domains due to the thermal expansion across the burning front--the Landau-Darrieus instability. This instability leads to wrinkling and growth of the flame surface, and corresponding acceleration of the flame, until it is stabilized by cusp formation. We look at the Landau-Darrieus in stability for C/O thermonuclear flames at conditions relevant to the late stages of a Type Ia supernova explosion. Two-dimensional direct numerical simulations of both single-mode and multi-mode perturbations using a low Mach number hydrodynamics code are presented. We show the effect of the instability on the flame speed as a function of both the density and domain size, demonstrate the existence of the small scale cutoff to the growth of the instability, and look for the proposed breakdown of the non-linear stabilization at low densities. The effects of curvature on the flame as quantified through measurements of the growth rate and computation of the corresponding Markstein number. While accelerations of a few percent are observed, they are too small to have any direct outcome on the supernova explosion.

Bell, J.B.; Day, M.S.; Rendleman, C.A.; Woosley, S.E.; Zingale, M.

2003-11-24T23:59:59.000Z

330

Comparison of the Legacy and Gold SnIa Dataset Constraints on Dark Energy Models  

E-Print Network [OSTI]

We have performed a comparative analysis of three recent and reliable SnIa datasets available in the literature: the Full Gold (FG) dataset (157 data points $0dataset (140 data points $0dataset (115 data points $0datasets are consistent with each other at the 95% confidence level, the latest (SNLS) dataset shows distinct trends which are not shared by the Gold datasets. We find that the best fit dynamical $w(z)$ obtained from the SNLS dataset does not cross the PDL $w=-1$ and remains above and close to the $w=-1$ line for the whole redshift range $0datasets (FG and TG) clearly crosses the PDL and departs significantly from the PDL $w=-1$ line while the LCDM parameter values are about $2\\sigma$ away from the best fit $w(z)$. In addition, the $(\\Omega_{0m},\\Omega_\\Lambda)$ parameters in a LCDM parametrization without a flat prior, fit by the SNLS dataset, favor the minimal flat LCDM concordance model. The corresponding fit with the Gold datasets mildly favors a closed universe and the flat LCDM parameter values are $1\\sigma - 2\\sigma$ away from the best fit $(\\Omega_{0m},\\Omega_\\Lambda)$.

S. Nesseris; L. Perivolaropoulos

2005-12-02T23:59:59.000Z

331

Phenomenology for Supernova Ia Data Based on a New Cosmic Time  

E-Print Network [OSTI]

A new phenomenological theory for the expansion of our universe is presented. Because fundamental supporting theory is still in development, its discussion is not presented in this paper. The theory is based on a new algebraic expression for cosmic time G Rho t^2=3/32Pi, which correctly predicts the WMAP measured cosmological constants and the fundamental Hubble parameter H(t) for the expansion of the universe. A replacement for dark matter, called here "dark mass", is proposed which scales as with the expansion and incorporated. It does not react with ordinary matter, except gravitationally, and produces flat rotational curves for spiral galaxies. Also a new expression for the approaching velocity of radiation in a closed 3-sphere expanding universe is given that accounts for the early degrading negative approach of radiation for z > 1.7. The expression is v = Hr-c. Combining these three elements produces a luminosity distance dL that successfully predicts the apparent magnitude of exploding supernova Ia stars and even the new gamma ray bursts with no need for dark energy or acceleration of the expansion of the universe.

Charles B. Leffert

2007-07-26T23:59:59.000Z

332

Magnitude-Redshift Relation for SNe Ia, Time Dilation, and Plasma Redshift  

E-Print Network [OSTI]

We have previously shown that the type Ia supernovae data by Riess et al. match the prediction of the magnitude-redshift relation in the plasma-redshift cosmology. In this article, we also show that the recent SNLS data, which have a slightly narrower distribution as reported by Astier et al. in 2005, match the predictions of the plasma-redshift cosmology. The standard deviation of the SNLS-magnitude from the predicted curve is only about 0.14. The data indicate that there is no cosmic time dilation. The big-bang cosmology therefore appears false. The plasma redshift, which follows from exact evaluation of photons interaction with hot sparse electron plasma, leads to a quasi-static, infinite, and everlasting universe. It does not need big bang, dark energy, or dark matter for describing the observations. It predicts intrinsic redshifts of galaxies consistent with what is observed. The Hubble constant that best fits the SNLS data is about 63 km per sec per Mpc. This corresponds to an average electron density of about 0.0002 per cubic centimeter in intergalactic space. This density together with the plasma redshift heating to an average plasma temperature in intergalactic space of about 3 million K explains the observed isotropic cosmic microwave background (CMB) and the cosmic X-ray background.

Ari Brynjolfsson

2006-02-22T23:59:59.000Z

333

A Test of Tully-Fisher Distance Estimates Using Cepheids and Type Ia Supernovae  

E-Print Network [OSTI]

We update and extend the results of Shanks (1997, MNRAS, 290, L77) by making a direct test of Tully-Fisher distance estimates to thirteen spiral galaxies with HST Cepheid distances and to ten spiral galaxies with Type Ia supernova (SNIa) distances. The results show that the Tully-Fisher distance moduli are too short with respect to the Cepheid distances by 0.46+-0.11mag and too short with respect to the SNIa distances by 0.49+-0.18mag. Combining the HST Cepheid and the best SNIa data suggests that, overall, previous Tully-Fisher distances at v~1000 kms-1 were too short by 0.43+-0.09mag, a result which is significant at the 4.6 sigma level. These data therefore indicate that previous Tully-Fisher distances should be revised upwards by 22+-5% implying, for example, a Virgo distance of 19.0+-1.8Mpc. The value of Ho from Tully-Fisher estimates is correspondingly revised downwards from Ho=84+-10kms-1Mpc-1 to Ho=69+-8kms-1Mpc-1. There is evidence that the Tully-Fisher relation at large distances is affected by Malmquist bias. In this case, we argue that Ho<50kms-1Mpc-1 cannot be ruled out by Tully-Fisher considerations.

T. Shanks

1999-01-24T23:59:59.000Z

334

FIRST EVIDENCE OF GLOBULAR CLUSTER FORMATION FROM THE EJECTA OF PROMPT TYPE Ia SUPERNOVAE  

SciTech Connect (OSTI)

Recent spectroscopic observations of globular clusters (GCs) in the Large Magellanic Cloud (LMC) have discovered that one of the intermediate-age GCs, NGC 1718, with [Fe/H] = -0.7 has an extremely low [Mg/Fe] ratio of {approx}-0.9. We propose that NGC 1718 was formed from the ejecta of Type Ia supernovae mixed with very metal-poor ([Fe/H] <-1.3) gas about {approx}2 Gyr ago. The proposed scenario is shown to be consistent with the observed abundances of Fe-group elements such as Cr, Mn, and Ni. In addition, compelling evidence for asymptotic giant branch stars playing a role in chemical enrichment during this GC formation is found. We suggest that the origin of the metal-poor gas is closely associated with efficient gas transfer from the outer gas disk of the Small Magellanic Cloud to the LMC disk. We anticipate that the outer part of the LMC disk contains field stars exhibiting significantly low [Mg/Fe] ratios, formed through the same process as NGC 1718.

Tsujimoto, Takuji [National Astronomical Observatory of Japan, Mitaka-shi, Tokyo 181-8588 (Japan); Bekki, Kenji, E-mail: taku.tsujimoto@nao.ac.jp [ICRAR, M468, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009 (Australia)

2012-06-01T23:59:59.000Z

335

E-Print Network 3.0 - aceros al cr-mo-v Sample Search Results  

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

G. F. Janssens, Dierk Raabe, Ernst Kozeschnik, Mark A. Miodownik, Summary: , ,,Dissimilar 2.25Cr-9Cr and 2Cr-0.5CrMoV steel welds, I. Characterisation of the weld zone and...

336

Growth and crystal structure of binary molybdate CsFe(MoO{sub 4}){sub 2}  

SciTech Connect (OSTI)

CsFe(MoO{sub 4}){sub 2} single crystals have been grown by solution-melt crystallization with a charge-to-solvent ratio of 1: 3 (with Cs{sub 2}Mo{sub 3}O{sub 10} used as a solvent). The crystal structure of this compound has been refined by X-ray diffraction (X8 APEX automatic diffractometer, MoK{sub {alpha}} radiation, 356 F(hkl), R = 0.0178). The trigonal unit cell has the following parameters: a = b = 5.6051(2) A, c = 8.0118(4) A, V = 217.985(15) A{sup 3}, Z = 1, {rho}{sub calc} = 3.875 g/cm{sup 3}, and sp. gr. P3-barm1. The structure is composed of alternating layers of FeO{sub 6} octahedra (with MoO{sub 4} tetrahedra attached by sharing vertices) and CsO{sub 12} icosahedra.

Bazarov, B. G., E-mail: jbaz@binm.bscnet.ru; Namsaraeva, T. V. [Russian Academy of Sciences, Baikal Institute of Nature Management, Siberian Branch (Russian Federation); Klevtsova, R. F., E-mail: klev@che.nsk.su; Anshits, A. G. [Russian Academy of Sciences, Institute of Inorganic Chemistry, Siberian Branch (Russian Federation); Vereshchagina, T. A. [Russian Academy of Sciences, Institute of Chemistry and Chemical Technology, Siberian Branch (Russian Federation); Glinskaya, L. A. [Russian Academy of Sciences, Institute of Inorganic Chemistry, Siberian Branch (Russian Federation); Fedorov, K. N.; Bazarova, Zh. G. [Russian Academy of Sciences, Baikal Institute of Nature Management, Siberian Branch (Russian Federation)

2010-07-15T23:59:59.000Z

337

Combining sedimentological, trace metal (Mn, Mo) and molecular evidence for reconstructing past water-column  

E-Print Network [OSTI]

Combining sedimentological, trace metal (Mn, Mo) and molecular evidence for reconstructing past online 22 June 2013 Abstract Here, we present sedimentological, trace metal, and molecular evidence underscores the value of combining sedimentological, geochemical, and microbiological approaches

Wehrli, Bernhard

338

Monolayers of MoS{sub 2} as an oxidation protective nanocoating material  

SciTech Connect (OSTI)

First-principle calculations are employed to investigate the interaction of oxygen with ideal and defective MoS{sub 2} monolayers. Our calculations show that while oxygen atoms are strongly bound on top of sulfur atoms, the oxygen molecule only weakly interacts with the surface. The penetration of oxygen atoms and molecules through a defect-free MoS{sub 2} monolayer is prevented by a very high diffusion barrier indicating that MoS{sub 2} can serve as a protective layer for oxidation. The analysis is extended to WS{sub 2} and similar coating characteristics are obtained. Our calculations indicate that ideal and continuous MoS{sub 2} and WS{sub 2} monolayers can improve the oxidation and corrosion-resistance of the covered surface and can be considered as an efficient nanocoating material.

Sen, H. Sener [UNAM-National Nanotechnology Research Center, Bilkent University, Ankara 06800 (Turkey); Sahin, H.; Peeters, F. M. [Department of Physics, University of Antwerp, 2610 Antwerp (Belgium); Durgun, E., E-mail: durgun@unam.bilkent.edu.tr [UNAM-National Nanotechnology Research Center, Bilkent University, Ankara 06800 (Turkey); Institute of Materials Science and Nanotechnology, Bilkent University, Ankara 06800 (Turkey)

2014-08-28T23:59:59.000Z

339

Electronic structure and conductivity of nanocomposite metal (Au,Ag,Cu,Mo)-containing amorphous carbon films  

E-Print Network [OSTI]

dual-cathode arc deposition (PDC-FCVA) source containingand metal cathodes [2]. The PDC-FCVA system in combinationCu,Mo) incorporation in a-C by PDC-FCVA. The modification of

Endrino, Jose L.

2010-01-01T23:59:59.000Z

340

Atomistic simulation of the electronic states of adatoms in monolayer MoS{sub 2}  

SciTech Connect (OSTI)

Using an ab initio density functional theory based electronic structure method, we study the effects of adatoms on the electronic properties of monolayer transition metal dichalcogenide Molybdenum-disulfide (MoS{sub 2}). We consider the 1st (Li, Na, K) and 7th (F, Cl, Br) column atoms and metals (Sc, Ti, Ta, Mo, Pd, Pt, Ag, Au). Three high symmetry sites for the adatom on the surface of monolayer MoS{sub 2} are examined as starting points to search for the most energetically stable configuration for each adatom-monolayer MoS{sub 2} system, as well as the type of associated bonding. For the most stable adatom positions, we characterize the emergence of adatom-induced electronic states including any dopant states.

Chang, Jiwon; Larentis, Stefano; Tutuc, Emanuel; Register, Leonard F.; Banerjee, Sanjay K. [Microelectronics Research Center, The University of Texas at Austin, Austin, Texas 78758 (United States)

2014-04-07T23:59:59.000Z

Note: This page contains sample records for the topic "ia mo ar" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

AB INITIO Modeling of Thermomechanical Properties of Mo-Based Alloys for Fossil Energy Conversion  

SciTech Connect (OSTI)

In this final scientific/technical report covering the period of 3.5 years started on July 1, 2011, we report the accomplishments on the study of thermo-mechanical properties of Mo-based intermetallic compounds under NETL support. These include computational method development, physical properties investigation of Mo-based compounds and alloys. The main focus is on the mechanical and thermo mechanical properties at high temperature since these are the most crucial properties for their potential applications. In particular, recent development of applying ab initio molecular dynamic (AIMD) simulations to the T1 (Mo{sub 5}Si{sub 3}) and T2 (Mo{sub 5}SiB{sub 2}) phases are highlighted for alloy design in further improving their properties.

Ching, Wai-Yim

2013-12-31T23:59:59.000Z

342

Enhanced absorption of monolayer MoS{sub 2} with resonant back reflector  

SciTech Connect (OSTI)

The optical absorption of monolayer MoS{sub 2} on top of one-dimensional photonic crystal (1DPC) or metal films with spacer layers is theoretically investigated by extracting the permittivity of monolayer MoS{sub 2} from existing experimental results [K. F. Mak et al., Phys. Rev. Lett. 105, 136805 (2010)]. The absorption of graphene with 1DPC across a broad spectral range is substantially enhanced because of the photonic localization at the optical micro-cavity on top of the 1DPC or metal films. The absorption of monolayer MoS{sub 2} can be tuned by varying either the distance between the monolayer MoS{sub 2} and the back reflector or the thickness of the cover layers.

Liu, Jiang-Tao, E-mail: jtliu@semi.ac.cn; Liu, Nian-Hua [Nanoscale Science and Technology Laboratory, Institute for Advanced Study, Nanchang University, Nanchang 330031 (China); Department of Physics, Nanchang University, Nanchang 330031 (China); Wang, Tong-Biao [Department of Physics, Nanchang University, Nanchang 330031 (China); Li, Xiao-Jing [College of Physics and Energy, Fujian Normal University, Fuzhou 350007 (China)

2014-05-21T23:59:59.000Z

343

Mo{sub 5}Si{sub 3} single crystals: Physical properties and mechanical behavior  

SciTech Connect (OSTI)

The materials processing, physical properties and mechanical behavior of an ultra-high temperature structural silicide, Mo{sub 5}Si{sub 3}, have been studied. High purity single crystals of Mo{sub 5}Si{sub 3} have been synthesized by both optical floating zone and Czochralski methods. The thermal and elastic properties of the MO{sub 5}Si{sub 3} single crystals were experimentally measured. Results show that Mo{sub 5}Si{sub 3} has significant thermal expansion anisotropy along the a and c directions with {alpha}{sub c}/{alpha}{sub a} = 2.2. Single crystal elastic moduli of Mo{sub 5}Si{sub 3} indicate that it has less elastic anisotropy and lower shear moduli than transition metal disilicides. Tensile stresses of up to 1.8 GPa can develop at grain boundaries after cooling from the melting point due to the thermal expansion mismatch in Mo{sub 5}Si{sub 3}, causing grain boundary cracking during processing of polycrystals. Room temperature Vickers indentation tests on (100) and (001) planes have been performed with different indenter diagonal orientations. The orientation dependence of hardness and fracture toughness of Mo{sub 5}Si{sub 3} single crystals have been obtained. The corresponding deformation and fracture modes have been revealed by microscopy studies. A comparison of Mo{sub 5}Si{sub 3} with other high temperature structural silicides, e.g., C11{sub b} and C40 transition metal disilicides, is discussed.

Chu, F.; Thoma, D.J.; McClellan, K.J.; Peralta, P.

1998-12-01T23:59:59.000Z

344

Description of coordinatively unsaturated sites regeneration over MoS2-based HDS catalysts using 35  

E-Print Network [OSTI]

envisaged. Moreover, on the sulfur edge the H2S release activation energy is too high (~ 13.5 kcal.mol-1 likely to occur on the MoS2 metallic edge through the departure of an H2S molecule. In the present paper, we aimed at examining the H2S departure from MoS2 catalysts promoted with Co and Ni. The [35 S

Boyer, Edmond

345

The Rise and Fall of Type Ia Supernova Light Curves in the SDSS-II Supernova Survey  

SciTech Connect (OSTI)

We analyze the rise and fall times of Type Ia supernova (SN Ia) light curves discovered by the Sloan Digital Sky Survey-II (SDSS-II) Supernova Survey. From a set of 391 light curves k-corrected to the rest-frame B and V bands, we find a smaller dispersion in the rising portion of the light curve compared to the decline. This is in qualitative agreement with computer models which predict that variations in radioactive nickel yield have less impact on the rise than on the spread of the decline rates. The differences we find in the rise and fall properties suggest that a single 'stretch' correction to the light curve phase does not properly model the range of SN Ia light curve shapes. We select a subset of 105 light curves well observed in both rise and fall portions of the light curves and develop a '2-stretch' fit algorithm which estimates the rise and fall times independently. We find the average time from explosion to B-band peak brightness is 17.38 {+-} 0.17 days, but with a spread of rise times which range from 13 days to 23 days. Our average rise time is shorter than the 19.5 days found in previous studies; this reflects both the different light curve template used and the application of the 2-stretch algorithm. The SDSS-II supernova set and the local SNe Ia with well-observed early light curves show no significant differences in their average rise-time properties. We find that slow-declining events tend to have fast rise times, but that the distribution of rise minus fall time is broad and single peaked. This distribution is in contrast to the bimodality in this parameter that was first suggested by Strovink (2007) from an analysis of a small set of local SNe Ia. We divide the SDSS-II sample in half based on the rise minus fall value, t{sub r} - t{sub f} {approx}< 2 days and t{sub r} - t{sub f} > 2 days, to search for differences in their host galaxy properties and Hubble residuals; we find no difference in host galaxy properties or Hubble residuals in our sample.

Hayden, Brian T.; /Notre Dame U.; Garnavich, Peter M.; /Notre Dame U.; Kessler, Richard; /KICP, Chicago /Chicago U., EFI; Frieman, Joshua A.; /KICP, Chicago /Chicago U. /Fermilab; Jha, Saurabh W.; /Stanford U., Phys. Dept. /Rutgers U., Piscataway; Bassett, Bruce; /Cape Town U., Dept. Math. /South African Astron. Observ.; Cinabro, David; /Wayne State U.; Dilday, Benjamin; /Rutgers U., Piscataway; Kasen, Daniel; /UC, Santa Cruz; Marriner, John; /Fermilab; Nichol, Robert C.; /Portsmouth U., ICG /Baltimore, Space Telescope Sci. /Johns Hopkins U.

2010-01-01T23:59:59.000Z

346

Soft zone formation in dissimilar welds between two Cr-Mo steels  

SciTech Connect (OSTI)

Two dissimilar weldments between 9Cr-1Mo and 2.25Cr-1Mo ferritic steels have been characterized for their microstructural stability during various postweld heat treatments (PWHTs). The samples for the investigation were extracted from bead-on-plate weldments made by depositing 2.25Cr-1Mo weld metal on 9Cr-1Mo base plate and vice versa. Subsequent application of PWHT resulted in the formation of a soft zone in the low Cr ferritic steel weld or base plate. A carbide-rich hard zone, adjoining the soft zone, was also detected in the high Cr side of the weldment. Unmixed zones in the weld metal provided additional soft and hard zones in the weld metals. The migration of carbon from low-Cr steel to high-Cr steel, driven by the carbon activity gradient, has been shown to be responsible for the formation of soft and hard zones. A carbon activity diagram for 2.25Cr-1Mo/9Cr-1Mo weldments has been proposed to aid in the selection of welding consumables for reducing or preventing the soft zone formation.

Albert, S.K.; Gill, T.P.S.; Tyagi, A.K.; Mannan, S.L.; Rodriguez, P. [Indira Gandhi Centre for Atomic Research, Kalpakkam (India); Kulkarni, S.D. [Indian Inst. of Tech., Bombay (India)

1997-03-01T23:59:59.000Z

347

Food and Drug Administration process validation activities to support 99Mo production at Sandia National Laboratories  

SciTech Connect (OSTI)

Prior to 1989 {sup 99}Mo was produced in the US by a single supplier, Cintichem Inc., Tuxedo, NY. Because of problems associated with operating its facility, in 1989 Cintichem elected to decommission the facility rather than incur the costs for repair. The demise of the {sup 99}Mo capability at Cintichem left the US totally reliant upon a single foreign source, Nordion International, located in Ottawa Canada. In 1992 the DOE purchased the Cintichem {sup 99}Mo Production Process and Drug Master File (DMF). In 1994 the DOE funded Sandia National Laboratories (SNL) to produce {sup 99}Mo. Although Cintichem produced {sup 99}Mo and {sup 99m}Tc generators for many years, there was no requirement for process validation which is now required by the Food and Drug Administration (FDA). In addition to the validation requirement, the requirements for current Good manufacturing Practices were codified into law. The purpose of this paper is to describe the process validation being conducted at SNL for the qualification of SNL as a supplier of {sup 99}Mo to US pharmaceutical companies.

McDonald, M.J.; Bourcier, S.C.; Talley, D.G.

1997-07-01T23:59:59.000Z

348

MoS{sub 2} nanotube exfoliation as new synthesis pathway to molybdenum blue  

SciTech Connect (OSTI)

Graphical abstract: . Display Omitted Highlights: ? New synthesis approach to obtaining molybdenum blue via exfoliated MoS{sub 2} nanotubes. ? Material is prone to self assembly and is stable in high vacuum. ? Molecules are as small as 2 nm and their clusters are up to tens of nanometers. ? Change in absorption and oxidation states from the precursor MoS{sub 2}. -- Abstract: Molybdenum blue-type materials are usually obtained by partially reducing Mo{sup VI+} in acidic solutions, while in the presented method it is formed in ethanol solution of exfoliated MoS{sub 2} nanotubes, where the MoS{sub 2} flakes are the preferential location for their growth. Material was investigated by means of scanning electron and atomic force microscopy, showing the structure and self assembly, while also confirming that it is stable in high vacuum with molecules as small as 1.6 nm and the agglomerates of few tens of nanometres. The ultraviolet–visible and photoelectron spectrometry show the change in absorption properties and oxidation states from MoS{sub 2} structure to molybdenum blue, while the presence of sulphur suggests that this is a new type of molybdenum blue material.

Visic, B., E-mail: bojana.visic@ijs.si [Jozef Stefan Institute, Jamova cesta 39, SI-1000 Ljubljana (Slovenia); Gunde, M. Klanjsek [National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana (Slovenia)] [National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana (Slovenia); Kovac, J.; Iskra, I. [Jozef Stefan Institute, Jamova cesta 39, SI-1000 Ljubljana (Slovenia)] [Jozef Stefan Institute, Jamova cesta 39, SI-1000 Ljubljana (Slovenia); Jelenc, J.; Remskar, M. [Jozef Stefan Institute, Jamova cesta 39, SI-1000 Ljubljana (Slovenia) [Jozef Stefan Institute, Jamova cesta 39, SI-1000 Ljubljana (Slovenia); Centre of Excellence Namaste, Jamova cesta 39, SI-1000 Ljubljana (Slovenia)

2013-02-15T23:59:59.000Z

349

E-Print Network 3.0 - ar para uma Sample Search Results  

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

(Figura 6.d). Uma vez escolhido o ar- quivo, uma transio de... fato a existn- cia de ... Source: Barbosa, Alberto - Departamento de Informtica, Pontifcia...

350

SPPI ORIGINAL PAPER October 11, 2011 GROSS ERRORS IN THE IPCC-AR4  

E-Print Network [OSTI]

SPPI ORIGINAL PAPER October 11, 2011 GROSS ERRORS IN THE IPCC-AR4 REPORT REGARDING PAST & FUTURE FIGURE AND GEORGE WILL QUOTE.....................

Gray, William

351

E-Print Network 3.0 - androgen receptor ar Sample Search Results  

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

Baldness and the androgen receptor: the AR polyglycine repeat polymorphism does... ., Marschke, C., Hiort, O., 2006. The A645D mutation in the ... Source: Ecole Polytechnique,...

352

Oxygen-driven relaxation processes in pre-irradiated Ar cryocrystals  

E-Print Network [OSTI]

Excitations of Solid Oxygen ?in Russian?, B. I. Verkin andNUMBER 11 NOVEMBER 2006 Oxygen-driven relaxation processes? Relaxation processes in oxygen-containing Ar cryocrystals

Savchenko, E. V; Belov, A. G; Gumenchuk, G. B; Ponomaryov, A. N; Bondybey, V. E

2006-01-01T23:59:59.000Z

353

E-Print Network 3.0 - ar-bicat diimine platinum Sample Search...  

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

Sample search results for: ar-bicat diimine platinum Page: << < 1 2 3 4 5 > >> 1 Chemistry Department 2011 Summer Research Program Summary: are investigating the interaction...

354

E-Print Network 3.0 - advanced ring pf-ar Sample Search Results  

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

for: advanced ring pf-ar Page: << < 1 2 3 4 5 > >> 1 Advanced Computer Systems Architecture Summary: Advanced Computer Systems Architecture Highly Integrated...

355

Dusty Plasma in He-Ar Glow Discharge  

SciTech Connect (OSTI)

The paper reports on the first experiments with plasma-dust formations in dc gas discharge plasma for He-Ar mixture. It is shown that under the conventional conditions of the experiments with dusty structures in plasma, the choice of light and heavy gases for the mixture suppresses electron heating in electric field and results in a supersonic jet with high Mach numbers. Distribution functions for drifting ions in the gas mixture are calculated for various mixture concentrations, electric field strengths and gas pressures.

Maiorov, S. A. [A. M. Prokhorov Institute for General Physics under Russian Academy of Sciences, Moscow (Russian Federation); Ramazanov, T. S.; Dzhumagulova, K. N.; Dosbolayev, M. K.; Jumabekov, A. N. [IETP, al-Farabi Kazakh National University, 96a, Tole bi St., Almaty, 050012 (Kazakhstan)

2008-09-07T23:59:59.000Z

356

THE HUBBLE SPACE TELESCOPE CLUSTER SUPERNOVA SURVEY. III. CORRELATED PROPERTIES OF TYPE Ia SUPERNOVAE AND THEIR HOSTS AT 0.9 < z < 1.46  

SciTech Connect (OSTI)

Using the sample of Type Ia supernovae (SNe Ia) discovered by the Hubble Space Telescope (HST) Cluster Supernova Survey and augmented with HST-observed SNe Ia in the Great Observatories Origins Deep Survey (GOODS) fields, we search for correlations between the properties of SNe and their host galaxies at high redshift. We use galaxy color and quantitative morphology to determine the red sequence in 25 clusters and develop a model to distinguish passively evolving early-type galaxies from star-forming galaxies in both clusters and the field. With this approach, we identify 6 SN Ia hosts that are early-type cluster members and 11 SN Ia hosts that are early-type field galaxies. We confirm for the first time at z > 0.9 that SNe Ia hosted by early-type galaxies brighten and fade more quickly than SNe Ia hosted by late-type galaxies. We also show that the two samples of hosts produce SNe Ia with similar color distributions. The relatively simple spectral energy distributions expected for passive galaxies enable us to measure stellar masses of early-type SN hosts. In combination with stellar mass estimates of late-type GOODS SN hosts from Thomson and Chary, we investigate the correlation of host mass with Hubble residual observed at lower redshifts. Although the sample is small and the uncertainties are large, a hint of this relation is found at z > 0.9. By simultaneously fitting the average cluster galaxy formation history and dust content to the red-sequence scatters, we show that the reddening of early-type cluster SN hosts is likely E(B - V) {approx}< 0.06. The similarity of the field and cluster early-type host samples suggests that field early-type galaxies that lie on the red sequence may also be minimally affected by dust. Hence, the early-type-hosted SNe Ia studied here occupy a more favorable environment to use as well-characterized high-redshift standard candles than other SNe Ia.

Meyers, J.; Barbary, K.; Fakhouri, H. K.; Goldhaber, G. [Department of Physics, University of California Berkeley, Berkeley, CA 94720 (United States); Aldering, G.; Faccioli, L.; Hsiao, E. [E.O. Lawrence Berkeley National Lab, 1 Cyclotron Rd., Berkeley, CA 94720 (United States); Barrientos, L. F. [Departmento de Astronomia, Pontificia Universidad Catolica de Chile, Santiago (Chile); Brodwin, M. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Dawson, K. S. [Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112 (United States); Deustua, S.; Fruchter, A. S. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Doi, M.; Ihara, Y. [Institute of Astronomy, Graduate School of Science, University of Tokyo, 2-21-1 Osawa, Mitaka, Tokyo 181-0015 (Japan); Eisenhardt, P. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Gilbank, D. G. [Department of Physics and Astronomy, University Of Waterloo, Waterloo, Ontario, N2L 3G1 (Canada); Gladders, M. D. [Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637 (United States); Gonzalez, A. H. [Department of Astronomy, University of Florida, Gainesville, FL 32611 (United States); Hattori, T. [Subaru Telescope, National Astronomical Observatory of Japan, 650 North Aohaku Place, Hilo, HI 96720 (United States); Kashikawa, N., E-mail: jmeyers314@berkeley.edu [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Collaboration: Supernova Cosmology Project; and others

2012-05-01T23:59:59.000Z

357

Enriched Zn$^{100}$MoO$_4$ scintillating bolometers to search for $0 ? 2?$ decay of $^{100}$Mo with the LUMINEU experiment  

E-Print Network [OSTI]

The LUMINEU project aims at performing a demonstrator underground experiment searching for the neutrinoless double beta decay of the isotope $^{100}$Mo embedded in zinc molybdate (ZnMoO$_4$) scintillating bolometers. In this context, a zinc molybdate crystal boule enriched in $^{100}$Mo to 99.5\\% with a mass of 171 g was grown for the first time by the low-thermal-gradient Czochralski technique. The production cycle provided a high yield (the crystal boule mass was 84\\% of initial charge) and an acceptable level -- around 4\\% -- of irrecoverable losses of the costy enriched material. Two crystals of 59 g and 63 g, obtained from the enriched boule, were tested aboveground at milli-Kelvin temperature as scintillating bolometers. They showed a high detection performance, equivalent to that of previously developed natural ZnMoO$_4$ detectors. These results pave the way to future sensitive searches based on the LUMINEU technology, capable to approach and explore the inverted hierarchy region of the neutrino mass pattern.

A. S. Barabash; D. M. Chernyak; F. A. Danevich; A. Giuliani; I. M. Ivanov; E. P. Makarov; M. Mancuso; S. Marnieros; S. G. Nasonov; C. Nones; E. Olivieri; G. Pessina; D. V. Poda; V. N. Shlegel; M. Tenconi; V. I. Tretyak; Ya. V. Vasiliev; M. Velazquez; V. N. Zhdankov

2014-07-05T23:59:59.000Z

358

Evaluating systematic dependencies of type Ia supernovae : the influence of deflagration to detonation density.  

SciTech Connect (OSTI)

We explore the effects of the deflagration to detonation transition (DDT) density on the production of {sup 56}Ni in thermonuclear supernova (SN) explosions (Type Ia supernovae). Within the DDT paradigm, the transition density sets the amount of expansion during the deflagration phase of the explosion and therefore the amount of nuclear statistical equilibrium (NSE) material produced. We employ a theoretical framework for a well-controlled statistical study of two-dimensional simulations of thermonuclear SNe with randomized initial conditions that can, with a particular choice of transition density, produce a similar average and range of {sup 56}Ni masses to those inferred from observations. Within this framework, we utilize a more realistic 'simmered' white dwarf progenitor model with a flame model and energetics scheme to calculate the amount of {sup 56}Ni and NSE material synthesized for a suite of simulated explosions in which the transition density is varied in the range (1-3) x 10{sup 7} g cm{sup -3}. We find a quadratic dependence of the NSE yield on the log of the transition density, which is determined by the competition between plume rise and stellar expansion. By considering the effect of metallicity on the transition density, we find the NSE yield decreases by 0.055 {+-} 0.004 M {circle_dot} for a 1 Z {circle_dot} increase in metallicity evaluated about solar metallicity. For the same change in metallicity, this result translates to a 0.067 {+-} 0.004 M {circle_dot} decrease in the {sup 56}Ni yield, slightly stronger than that due to the variation in electron fraction from the initial composition. Observations testing the dependence of the yield on metallicity remain somewhat ambiguous, but the dependence we find is comparable to that inferred from some studies.

Jackson, A. P.; Calder, A. C.; Townsley, D. M.; Chamulak, D. A.; Brown, E. F.; Timmes, F. X. (Physics); (State Univ. of New York); (Univ. of Alabama); (Michigan State Univ.); (Arizona State Univ.); (Joint Inst. for Nuclear Astrophysics)

2010-09-01T23:59:59.000Z

359

EVALUATING SYSTEMATIC DEPENDENCIES OF TYPE Ia SUPERNOVAE: THE INFLUENCE OF DEFLAGRATION TO DETONATION DENSITY  

SciTech Connect (OSTI)

We explore the effects of the deflagration to detonation transition (DDT) density on the production of {sup 56}Ni in thermonuclear supernova (SN) explosions (Type Ia supernovae). Within the DDT paradigm, the transition density sets the amount of expansion during the deflagration phase of the explosion and therefore the amount of nuclear statistical equilibrium (NSE) material produced. We employ a theoretical framework for a well-controlled statistical study of two-dimensional simulations of thermonuclear SNe with randomized initial conditions that can, with a particular choice of transition density, produce a similar average and range of {sup 56}Ni masses to those inferred from observations. Within this framework, we utilize a more realistic 'simmered' white dwarf progenitor model with a flame model and energetics scheme to calculate the amount of {sup 56}Ni and NSE material synthesized for a suite of simulated explosions in which the transition density is varied in the range (1-3) x10{sup 7} g cm{sup -3}. We find a quadratic dependence of the NSE yield on the log of the transition density, which is determined by the competition between plume rise and stellar expansion. By considering the effect of metallicity on the transition density, we find the NSE yield decreases by 0.055 {+-} 0.004 M {sub sun} for a 1 Z{sub sun} increase in metallicity evaluated about solar metallicity. For the same change in metallicity, this result translates to a 0.067 {+-} 0.004 M{sub sun} decrease in the {sup 56}Ni yield, slightly stronger than that due to the variation in electron fraction from the initial composition. Observations testing the dependence of the yield on metallicity remain somewhat ambiguous, but the dependence we find is comparable to that inferred from some studies.

Jackson, Aaron P.; Calder, Alan C. [Department of Physics and Astronomy, State University of New York-Stony Brook, Stony Brook, NY (United States); Townsley, Dean M. [Department of Physics and Astronomy, University of Alabama, Tuscaloosa, AL (United States); Chamulak, David A. [Argonne National Laboratory, Argonne, IL (United States); Brown, Edward F.; Timmes, F. X. [Joint Institute for Nuclear Astrophysics, Michigan State University, East Lansing, MI 48824 (United States)

2010-09-01T23:59:59.000Z

360

Exploring Cosmological Expansion Parametrizations with the Gold SnIa Dataset  

E-Print Network [OSTI]

We use the SnIa Gold dataset to compare LCDM with 10 representative parametrizations of the recent Hubble expansion history $H(z)$. For the comparison we use two statistical tests; the usual $\\chi_{min}^2$ which is insensitive to the parametrization number of parameters, and a statistic we call the p-test which depends on both the value of $\\chi_{min}^2$ and the number $n$ of the parametrization parameters. The p-test measures the confidence level to which the parameter values corresponding to LCDM are excluded from the viewpoint of the parametrization tested. For example, for a linear equation of state parametrization $w(z)=w_0 + w_1 z$ the LCDM parameter values ($w_0=-1$, $w_1=0$) are excluded at 75% confidence level. We use a flat prior and $\\Omega_{0m}=0.3$. All parametrizations tested are consistent with the Gold dataset at their best fit. According to both statistical tests, the worst fits among the 10 parametrizations, correspond to the Chaplygin gas, the brane world and the Cardassian parametrizations. The best fit is achieved by oscillating parametrizations which can exclude the parameter values corresponding to LCDM at 85% confidence level. Even though this level of significance does not provide a statistically significant exclusion of LCDM (it is less than $2\\sigma$) and does not by itself constitute conclusive evidence for oscillations in the cosmological expansion, when combined with similar independent recent evidence for oscillations coming from the CMB and matter power spectra it becomes an issue worth of further investigation.

R. Lazkoz; S. Nesseris; L. Perivolaropoulos

2005-11-10T23:59:59.000Z

Note: This page contains sample records for the topic "ia mo ar" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

U.S. Energy Information Administration | Annual Energy Outlook...  

Annual Energy Outlook 2013 [U.S. Energy Information Administration (EIA)]

Figure F7. Coal Demand Regions CT,MA,ME,NH,RI,VT OH 1. NE 3. S1 4. S2 5. GF 6. OH 7. EN AL,MS MN,ND,SD IA,NE,MO,KS TX,LA,OK,AR MT,WY,ID CO,UT,NV AZ,NM 9. AM 11. C2 12. WS 13. MT...

362

Region 2007 2008 2009 2010 2011 2012 New England 183 140 138 140 127 136 -26%  

E-Print Network [OSTI]

17% Plains 45 48 50 60 53 59 31% Rocky Mountains 18 18 27 21 21 19 6% Southwest 56 61 61 57 64 83 48 Region Florida Atlantic University CO TX NMAZ UT NV CA OR WA WY ND SD NE KS OK MN WI MI IA MO IL AR AL AK New England Great Lakes Plains Rocky Mountains Far West Florida South west #12;

Fernandez, Eduardo

363

Control of absorption of monolayer MoS$_{2}$ thin-film transistor in one-dimensional defective photonic crystal  

E-Print Network [OSTI]

The light absorption and transmission of monolayer MoS$_{2}$ in a one-dimensional defective photonic crystal (d-1DPC) is theoretically investigated. The study shows that the strong interference effect decreases photon density in particular areas of the microcavity. The d-1DPC can reduce light absorption of monolayer MoS$_{2}$ and enhance light transmission. The impact of monolayer MoS$_{2}$ light absorption on the localization effect of photon is investigated when monolayer MoS$_{2}$ and the organic light-emitting diode are located in the same microcavity. However, monolayer MoS$_{2}$ does not reduce the localization effect of light by regulating the position of monolayer MoS$_{2}$ in the microcavity.

Yang, Fang-Fang; Xiao, Wen-bo; Liu, Jiang-Tao; Liu, Nian-Hua

2014-01-01T23:59:59.000Z

364

Very-high-order harmonic generation from Ar atoms and Ar+ ions in superintense pulsed laser fields: An ab initio self-interaction-free time-dependent density-functional approach  

E-Print Network [OSTI]

We present an ab initio nonpertubative investigation of the mechanisms responsible for the production of very-high-order harmonic generation (HHG) from Ar atoms and Ar+ ions by means of the self-interaction-free time-dependent density...

Carrera, Juan J.; Chu, Shih-I; Tong, X. M.

2005-06-21T23:59:59.000Z

365

arXiv:0904.0927v1[math.AG]6Apr2009 CALCULATING THE PARABOLIC CHERN CHARACTER OF A  

E-Print Network [OSTI]

characters chP ar 1 (E), chP ar 2 (E) and chP ar 3 (E). The basic idea is to use the formula given in [IS2

Simpson, Carlos

366

Asymptotic Inference for AR Models with Heavy-tailed G-GARCH Noises  

E-Print Network [OSTI]

Asymptotic Inference for AR Models with Heavy-tailed G-GARCH Noises Rongmao Zhang Department-tailed G-GARCH(1,1) noises. When the tail index of G-GARCH is within (0, 2), it is shown that the LSE and finance. Keywords: AR model, G-GARCH, heavy-tailed and stable processes 1 #12;1 Introduction Since

Ling, Shiqing

367

The Caribbean Low-Level Jet and Its Relationship with Precipitation in IPCC AR4 Models  

E-Print Network [OSTI]

The Caribbean Low-Level Jet and Its Relationship with Precipitation in IPCC AR4 Models ELINOR R Report (AR4) shows that all models have the ability to simulate the location and height of the Caribbean Caribbean and, hence, an overly strong CLLJ. The ability of the models to simulate the correlation between

Martin, Elinor R.

368

Le magn)sme ar)ficiel pour les gaz d'atomes froids Jean Dalibard  

E-Print Network [OSTI]

Le magné)sme ar)ficiel pour les gaz d'atomes froids Jean Dalibard Année 2013-14 Chaire Atomes et rayonnement Magné8sme ar8ficiel pour un atome isolé (I) #12;Simula8on du magné8sme avec des atomes neutres Le but : réaliser pour

Dalibard, Jean

369

Active species downstream of an ArO surface-wave microwave discharge for biomedicine,  

E-Print Network [OSTI]

Active species downstream of an Ar­O 2 surface-wave microwave discharge for biomedicine, surface.1088/0963-0252/20/3/035006 Active species downstream of an Ar­O2 surface-wave microwave discharge for biomedicine, surface treatment in a 0.5 cm diameter tube at pressures between 1 and 12 mbar. The early afterglow that occurs downstream

Guerra, Vasco

370

E-Print Network 3.0 - ar isotopic ratios Sample Search Results  

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

and Ecology 71 arXiv:1001.0944v2physics.atom-ph7May2010 Single-Photon Atomic Sorting: Isotope Separation with Maxwell's Demon Summary: arXiv:1001.0944v2physics.atom-ph7May201...

371

Beta. -MoO sub 3 produced from a novel freeze drying route  

SciTech Connect (OSTI)

Powdered samples of {beta}-MoO{sub 3} have been produced by the gentle heat treatment of freeze-dried molybdic acid at 350{degree}C for 1 hr. The samples, yellow-green in appearance, contained varying amounts of the thermodynamically stable {alpha}-MoO{sub 3}, depending upon the time and temperature of heat treatment. Neutron diffraction data were collected at 300 K. all peaks, not attributable to {alpha}-MoO{sub 3}, were indexed on the basis of a monoclinic cell, P2{sub 1}/c, {alpha} = 7.1228(7), b = 5.3660(6), c = 5.5665(6), {beta} = 92.01(1){degree}, V = 212.62(6){angstrom}{sup 3}. The structure, which is related to ReO{sub 3}, contains two crystallographically independent octahedra. Both show evidence of disorder at the Mo and O sites. Two distinct orientations of a short mo-O distance, suggestive of the type of molybdenyl bond observed in both the {alpha} and {beta}{prime}-forms, are primarily responsible for the observed disordering.

Parise, J.B. (State Univ. of New York, Stony Brook (United States)); McCarron, E.M. III (E.I. Dupont de Nemours and Co., Inc., Wilmington, DE (United States)); Von Dreele, R.; Goldstone, J.A. (Los Alamos National Lab., NM (United States))

1991-07-01T23:59:59.000Z

372

Oxidation and creep behavior of Mo*5*Si*3* based materials  

SciTech Connect (OSTI)

Mo{sub 5}Si{sub 3} shows promise as a high temperature creep resistant material. The high temperature oxidation resistance of Mo{sub 5}Si{sub 3} has been found to be poor, however, limiting its use in oxidizing atmospheres. Undoped Mo{sub 5}Si{sub 3} exhibits mass loss in the temperature range 800{degrees}-1200{degrees}C due to volatilization of molybdenum oxide, indicating that the silica scale does not provide a passivating layer. The addition of boron results in protective scale formation and parabolic oxidation kinetics in the temperature range of 1050{degrees}-1300{degrees}C. The oxidation rate of Mo{sub 5}Si{sub 3} was decreased by 5 orders of magnitude at 1200{degrees}C by doping with less than two weight percent boron. Boron doping eliminates catastrophic {open_quote}pest{close_quote} oxidation at 800{degrees}C. The mechanism for improved oxidation resistance of boron doped Mo{sub 5}Si{sub 3} is due to scale modification by boron.

Meyer, M.

1995-06-19T23:59:59.000Z

373

TEM Characterization of High Burn-up Microstructure of U-7Mo Alloy  

SciTech Connect (OSTI)

As an essential part of global nuclear non-proliferation effort, the RERTR program is developing low enriched U-Mo fuels (< 20% U-235) for use in research and test reactors that currently employ highly enriched uranium fuels. One type of fuel being developed is a dispersion fuel plate comprised of U-7Mo particles dispersed in Al alloy matrix. Recent TEM characterizations of the ATR irradiated U-7Mo dispersion fuel plates include the samples with a local fission densities of 4.5, 5.2, 5.6 and 6.3 E+21 fissions/cm3 and irradiation temperatures of 101-136?C. The development of the irradiated microstructure of the U-7Mo fuel particles consists of fission gas bubble superlattice, large gas bubbles, solid fission product precipitates and their association to the large gas bubbles, grain subdivision to tens or hundreds of nanometer size, collapse of bubble superlattice, and amorphisation. This presentation will describe the observed microstructures specifically focusing on the U-7Mo fuel particles. The impact of the observed microstructure on the fuel performance and the comparison of the relevant features with that of the high burn-up UO2 fuels will be discussed.

Jian Gan; Brandon Miller; Dennis Keiser; Adam Robinson; James Madden; Pavel Medvedev; Daniel Wachs

2014-04-01T23:59:59.000Z

374

Elementary Steps of Syngas Reactions on Mo2C(001): Adsorption Thermochemistry and Bond Dissociation  

SciTech Connect (OSTI)

Density functional theory (DFT) and ab initio thermodynamics are applied in order to investigate the most stable surface and subsurface terminations of Mo{sub 2}C(001) as a function of chemical potential and in the presence of syngas. The Mo-terminated (001) surface is then used as a model surface to evaluate the thermochemistry and energetic barriers for key elementary steps in syngas reactions. Adsorption energy scaling relations and Broensted-Evans-Polanyi relationships are established and used to place Mo{sub 2}C into the context of transition metal surfaces. The results indicate that the surface termination is a complex function of reaction conditions and kinetics. It is predicted that the surface will be covered by either C{sub 2}H{sub 2} or O depending on conditions. Comparisons to transition metals indicate that the Mo-terminated Mo{sub 2}C(001) surface exhibits carbon reactivity similar to transition metals such as Ru and Ir, but is significantly more reactive towards oxygen.

Medford, Andrew

2012-02-16T23:59:59.000Z

375

Method for the production of {sup 99m}Tc compositions from {sup 99}Mo-containing materials  

DOE Patents [OSTI]

An improved method is described for producing {sup 99m}Tc compositions from {sup 99}Mo compounds. {sup 100}Mo metal or {sup 100}MoO{sub 3} is irradiated with photons in a particle (electron) accelerator to ultimately produce {sup 99}MoO{sub 3}. This composition is then heated in a reaction chamber to form a pool of molten {sup 99}MoO{sub 3} with an optimum depth of 0.5--5 mm. A gaseous mixture thereafter evolves from the molten {sup 99}MoO{sub 3} which contains vaporized {sup 99}MoO{sub 3}, vaporized {sup 99m}TcO{sub 3}, and vaporized {sup 99m}TcO{sub 2}. This mixture is then combined with an oxidizing gas (O{sub 2(g)}) to generate a gaseous stream containing vaporized {sup 99m}Tc{sub 2}O{sub 7} and vaporized {sup 99}MoO{sub 3}. Next, the gaseous stream is cooled in a primary condensation stage in the reaction chamber to remove vaporized {sup 99}MoO{sub 3}. Cooling is undertaken at a specially-controlled rate to achieve maximum separation efficiency. The gaseous stream is then cooled in a sequential secondary condensation stage to convert vaporized {sup 99m}Tc{sub 2}O{sub 7} into a condensed {sup 99m}Tc-containing reaction product which is collected. 1 fig.

Bennett, R.G.; Christian, J.D.; Grover, S.B.; Petti, D.A.; Terry, W.K.; Yoon, W.Y.

1998-09-01T23:59:59.000Z

376

Method for the production of .sup.99m Tc compositions from .sup.99 Mo-containing materials  

DOE Patents [OSTI]

An improved method for producing .sup.99m Tc compositions from .sup.99 Mo compounds. .sup.100 Mo metal or .sup.100 MoO.sub.3 is irradiated with photons in a particle (electron) accelerator to ultimately produce .sup.99 MoO.sub.3. This composition is then heated in a reaction chamber to form a pool of molten .sup.99 MoO.sub.3 with an optimum depth of 0.5-5 mm. A gaseous mixture thereafter evolves from the molten .sup.99 MoO.sub.3 which contains vaporized .sup.99 MoO.sub.3, vaporized .sup.99m TcO.sub.3, and vaporized .sup.99m TcO.sub.2. This mixture is then combined with an oxidizing gas (O.sub.2(g)) to generate a gaseous stream containing vaporized .sup.99m Tc.sub.2 O.sub.7 and vaporized .sup.99 MoO.sub.3. Next, the gaseous stream is cooled in a primary condensation stage in the reaction chamber to remove vaporized .sup.99 MoO.sub.3. Cooling is undertaken at a specially-controlled rate to achieve maximum separation efficiency. The gaseous stream is then cooled in a sequential secondary condensation stage to convert vaporized .sup.99m Tc.sub.2 O.sub.7 into a condensed .sup.99m Tc-containing reaction product which is collected.

Bennett, Ralph G. (Idaho Falls, ID); Christian, Jerry D. (Idaho Falls, ID); Grover, S. Blaine (Idaho Falls, ID); Petti, David A. (Idaho Falls, ID); Terry, William K. (Idaho Falls, ID); Yoon, Woo Y. (Idaho Falls, ID)

1998-01-01T23:59:59.000Z

377

argillacea huebner caterpillars: Topics by E-print Network  

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

Des Moines, IA Caterpillar Mossville, IL Caterpillar Peoria, IL Cerner Kansas City, MO Eaton Naperville, IL Procter &Gamble (Oral B) Iowa City, IA RISE-Cancer Research Center...

378

Dual Feedback Controlled High Performance Ar Seeded ELMy H-mode Discharges in JET including Trace Tritium Experiments  

E-Print Network [OSTI]

Dual Feedback Controlled High Performance Ar Seeded ELMy H-mode Discharges in JET including Trace Tritium Experiments

379

Highly conducting SrMoO{sub 3} thin films for microwave applications  

SciTech Connect (OSTI)

We have measured the microwave resistance of highly conducting perovskite oxide SrMoO{sub 3} thin film coplanar waveguides. The epitaxial SrMoO{sub 3} thin films were grown by pulsed laser deposition and showed low mosaicity and smooth surfaces with a root mean square roughness below 0.3?nm. Layer-by-layer growth could be achieved for film thicknesses up to 400?nm as monitored by reflection high-energy electron diffraction and confirmed by X-ray diffraction. We obtained a constant microwave resistivity of 29???·cm between 0.1 and 20?GHz by refining the frequency dependence of the transmission coefficients. Our result shows that SrMoO{sub 3} is a viable candidate as a highly conducting electrode material for all-oxide microwave electronic devices.

Radetinac, Aldin, E-mail: aldin@oxide.tu-darmstadt.de; Mani, Arzhang; Ziegler, Jürgen; Alff, Lambert; Komissinskiy, Philipp, E-mail: komissinskiy@oxide.tu-darmstadt.de [Institute of Materials Science, TU Darmstadt, Alarich-Weiss-Str. 2, 64287 Darmstadt (Germany); Melnyk, Sergiy; Nikfalazar, Mohammad; Zheng, Yuliang; Jakoby, Rolf [Institute for Microwave Engineering and Photonics, TU Darmstadt, Merckstraße 25, 64283 Darmstadt (Germany)

2014-09-15T23:59:59.000Z

380

The development of uranium foil farication technology utilizing twin roll method for Mo-99 irradiation target  

E-Print Network [OSTI]

MDS Nordion in Canada, occupying about 75% of global supply of Mo-99 isotope, has provided the irradiation target of Mo-99 using the rod-type UAl sub x alloys with HEU(High Enrichment Uranium). ANL (Argonne National Laboratory) through co-operation with BATAN in Indonesia, leading RERTR (Reduced Enrichment for Research and Test Reactors) program substantially for nuclear non-proliferation, has designed and fabricated the annular cylinder of uranium targets, and successfully performed irradiation test, in order to develop the fabrication technology of fission Mo-99 using LEU(Low Enrichment Uranium). As the uranium foils could be fabricated in laboratory scale, not in commercialized scale by hot rolling method due to significant problems in foil quality, productivity and economic efficiency, attention has shifted to the development of new technology. Under these circumstances, the invention of uranium foil fabrication technology utilizing twin-roll casting method in KAERI is found to be able to fabricate LEU or...

Kim, C K; Park, H D

2002-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "ia mo ar" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Progress in chemical processing of LEU targets for {sup 99}Mo production -- 1997  

SciTech Connect (OSTI)

Presented here are recent experimental results of the continuing development activities associated with converting current processes for producing fission-product {sup 99}Mo from targets using high-enriched uranium (HEU) to low-enriched uranium (LEU). Studies were focused in four areas: (1) measuring the chemical behavior of iodine, rhodium, and silver in the LEU-modified Cintichem process, (2) performing experiments and calculations to assess the suitability of zinc fission barriers for LEU metal foil targets, (3) developing an actinide separations method for measuring alpha contamination of the purified {sup 99}Mo product, and (4) developing a cooperation with Sandia National Laboratories and Los Alamos National Laboratory that will lead to approval by the US Federal Drug Administration for production of {sup 99}Mo from LEU targets. Experimental results continue to show the technical feasibility of converting current HEU processes to LEU.

Vandegrift, G.F.; Conner, C.; Sedlet, J.; Wygmans, D.G. [Argonne National Lab., IL (United States); Wu, D. [Univ. of Illinois, Urbana, IL (United States); Iskander, F.; Landsberger, S. [Univ. of Texas, Austin, TX (United States)

1997-10-01T23:59:59.000Z

382

Atomistic full-band simulations of monolayer MoS{sub 2} transistors  

SciTech Connect (OSTI)

We study the transport properties of deeply scaled monolayer MoS{sub 2} n-channel metal-oxide-semiconductor field effect transistors (MOSFETs), using full-band ballistic quantum transport simulations, with an atomistic tight-binding Hamiltonian obtained from density functional theory. Our simulations suggest that monolayer MoS{sub 2} MOSFETs can provide near-ideal subthreshold slope, suppression of drain-induced barrier lowering, and gate-induced drain leakage. However, these full-band simulations exhibit limited transconductance. These ballistic simulations also exhibit negative differential resistance (NDR) in the output characteristics associated with the narrow width in energy of the lowest conduction band, but this NDR may be substantially reduced or eliminated by scattering in MoS{sub 2}.

Chang, Jiwon; Register, Leonard F.; Banerjee, Sanjay K. [Microelectronics Research Center, The University of Texas at Austin, Austin, Texas 78758 (United States)] [Microelectronics Research Center, The University of Texas at Austin, Austin, Texas 78758 (United States)

2013-11-25T23:59:59.000Z

383

Time exposure performance of Mo-Au Gibbsian segregating alloys for extreme ultraviolet collector optics  

SciTech Connect (OSTI)

Successful implementation of extreme ultraviolet (EUV) lithography depends on research and progress toward minimizing collector optics degradation from intense plasma erosion and debris deposition. Thus studying the surface degradation process and implementing innovative methods, which could enhance the surface chemistry causing the mirrors to suffer less damage, is crucial for this technology development. A Mo-Au Gibbsian segregation (GS) alloy is deposited on Si using a dc dual-magnetron cosputtering system and the damage is investigated as a result of time dependent exposure in an EUV source. A thin Au segregating layer is maintained through segregation during exposure, even though overall erosion in the Mo-Au sample is taking place in the bulk. The reflective material, Mo, underneath the segregating layer is protected by this sacrificial layer, which is lost due to preferential sputtering. In addition to theoretical work, experimental results are presented on the effectiveness of the GS alloys to be used as potential EUV collector optics material.

Qiu Huatan; Srivastava, Shailendra N.; Thompson, Keith C.; Neumann, Martin J.; Ruzic, David N

2008-05-01T23:59:59.000Z

384

DENSITY-FUNCTIONAL STUDY OF U-Mo AND U-Zr ALLOYS  

SciTech Connect (OSTI)

Density-functional theory previously used to describe phase equilibria in U-Zr alloys [A. Landa, P. Soederlind, P.E.A. Turchi, J. Alloys Comp. 478 (2009) 103-110] is extended to investigate the ground-state properties of U-Mo solid solutions. We discuss how the heat of formation in both alloys correlates with the charge transfer between the alloy components, and how the specific behavior of the density of states in the vicinity of the Fermi level promotes the stabilization of the U{sub 2}Mo compound. Our calculations prove that, due to the existence of a single {gamma}-phase over the typical fuel operation temperatures, {gamma}-U-Mo alloys should indeed have much lower constituent redistribution than {gamma}-U-Zr alloys for which binodal decomposition causes a high degree of constituent redistribution.

Landa, A; Soderlind, P; Turchi, P A

2010-11-01T23:59:59.000Z

385

Diversity in extinction laws of Type Ia supernovae measured between $0.2$ and $2\\,\\mu\\mathrm{m}$  

E-Print Network [OSTI]

We present ultraviolet (UV) observations of six nearby Type~Ia supernovae (SNe~Ia) obtained with the Hubble Space Telescope, three of which were also observed in the near-IR (NIR) with Wide-Field Camera~3. UV observations with the Swift satellite, as well as ground-based optical and near-infrared data provide complementary information. The combined data-set covers the wavelength range $0.2$--$2~\\mu$m. By also including archival data of SN 2014J, we analyse a sample spanning observed colour excesses up to $E(B-V)=1.4~$mag. We study the wavelength dependent extinction of each individual SN and find a diversity of reddening laws when characterised by the total-to-selective extinction $R_V$. In particular, we note that for the two SNe with $E(B-V)\\gtrsim1~$mag, for which the colour excess is dominated by dust extinction, we find $R_V=1.4\\pm0.1$ and $R_V=2.8\\pm0.1$. Adding UV photometry reduces the uncertainty of fitted $R_V$ by $\\sim50\\,$% allowing us to also measure $R_V$ of individual low-extinction objects whi...

Amanullah, R; Goobar, A; Ferretti, R; Papadogiannakis, S; Petrushevska, T; Brown, P J; Cao, Y; Contreras, C; Dahle, H; Elias-Rosa, N; Fynbo, J P U; Gorosabel, J; Guaita, L; Hangard, L; Howell, D A; Hsiao, E Y; Kankare, E; Kasliwal, M; Leloudas, G; Lundqvist, P; Mattila, S; Nugent, P; Phillips, M M; Sandberg, A; Stanishev, V; Sullivan, M; Taddia, F; Östlin, G; Asadi, S; Herrero-Illana, R; Jensen, J J; Karhunen, K; Lazarevi, S; Varenius, E; Santos, P; Sridhar, S Seethapuram; Wallström, S H J; Wiegert, J

2015-01-01T23:59:59.000Z

386

Toughness of Cr-Mo-V steels for steam-turbine rotors  

SciTech Connect (OSTI)

Cr-Mo-V steels are used extensively as the rotor material in the High Pressure and Intermediate Pressure Sections of modern steam turbines. The toughness of these rotors has a major influence on the reliability and efficiency of the turbine and the overall economy of operation and maintenance of the plant. The metallurgical factors affecting the toughness of the rotors and the methods to improve the toughness are now understood better than ever before. This paper will present a broad overview of the materials and design aspects of the toughness of Cr-Mo-V rotors with emphasis on the salient results of recent research programs aimed at improving their toughness.

Viswanathan, R.; Jaffee, R.I.

1982-04-01T23:59:59.000Z

387

Mo-99 production at the Annular Core Research Reactor - recent calculative results  

SciTech Connect (OSTI)

Significant progress has been made over the past year in understanding the chemistry and processing challenges associated with {sup 99}Mo production using Cintichem type targets. Targets fabricated at Los Alamos National Laboratory have been successfully irradiated in fuel element locations at the Annular Core Research Reactor (ACRR) and processed at the Sandia Hot Cell Facility. The next goal for the project is to remove the central cavity experiment tube from the reactor core, allowing for the irradiation of up to 37 targets. After the in-core work is complete, the reactor will be capable of producing significant quantities of {sup 99}Mo.

Parma, E.J.

1997-11-01T23:59:59.000Z

388

GAS AND DUST ABSORPTION IN THE DoAr 24E SYSTEM  

SciTech Connect (OSTI)

We present findings for DoAr 24E, a binary system that includes a classical infrared companion. We observed the DoAr 24E system with the Spitzer Infrared Spectrograph (IRS), with high-resolution, near-infrared spectroscopy of CO vibrational transitions, and with mid-infrared imaging. The source of high extinction toward infrared companions has been an item of continuing interest. Here we investigate the disk structure of DoAr 24E using the column densities, temperature, and velocity profiles of two CO absorption features seen toward DoAr 24Eb. We model the spectral energy distributions found using T-ReCS imaging and investigate the likely sources of extinction toward DoAr 24Eb. We find the lack of silicate absorption and small CO column density toward DoAr 24Eb suggest that the mid-infrared continuum is not as extinguished as the near-infrared, possibly due to the mid-infrared originating from an extended region. This, along with the velocity profile of the CO absorption, suggests that the source of high extinction is likely due to a disk or disk wind associated with DoAr 24Eb.

Kruger, Andrew J. [Department of Physical Science, Wilbur Wright College, 4300 North Narragansett Avenue, Chicago, IL 60634 (United States); Richter, Matthew J. [Department of Physics, University of California at Davis, One Shields Avenue, Davis, CA 95616 (United States); Seifahrt, Andreas [Department of Astronomy and Astrophysics, University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Carr, John S. [Remote Sensing Division, Naval Research Laboratory, Code 7210, Washington, DC 20375 (United States); Najita, Joan R. [National Optical Astronomy Observatory, Tucson, AZ 85719 (United States); Moerchen, Margaret M. [European Southern Observatory, Alonso de Cordova 3107, Santiago (Chile); Doppmann, Greg W. [W.M. Keck Observatory, 65-1120 Mamalahoa Hwy, Kamuela, HI 96743 (United States)

2012-11-20T23:59:59.000Z

389

Solar Energy Materials & Solar Cells 58 (1999) 199}208 The behaviour of Na implanted into Mo thin "lms  

E-Print Network [OSTI]

Solar Energy Materials & Solar Cells 58 (1999) 199}208 The behaviour of Na implanted into Mo thin, As ngstro( m Solar Center, P.O. Box 534, SE-751 21 Uppsala, Sweden Department of Materials Science Mo thin "lms used as back contacts for Cu(In,Ga)Se solar cells. The samples were analysed

Rockett, Angus

390

Materials Science and Engineering A261 (1999) 4452 Mo5Si3 single crystals: physical properties and mechanical behavior  

E-Print Network [OSTI]

. Among these phases, refractory metal silicides appear to be more attractive because of their ultra-high melting temperatures [1]. Among the refractory metal silicides, the silicides in the Mo­Si system show processing, physical properties and mechanical behavior of an ultrahigh temperature structural silicide, Mo5

391

11/04/02 G. W. Rubloff AVS 2002 MS MoA5 1 Spatially Programmable Reactor Design  

E-Print Network [OSTI]

optimization is constrained by fixed reactor design manufacturing #12;11/04/02 G. W. Rubloff ­ AVS 2002 ­ MS Mo spatial conditions in programmable reactor Uniformity unacceptable Produce high uniformity with optimal11/04/02 G. W. Rubloff ­ AVS 2002 ­ MS MoA5 1 Spatially Programmable Reactor Design: Toward a New

Rubloff, Gary W.

392

Giant Two-Photon Absorption Coefficient and Frequency Up-Converted Luminescence in Monolayer MoS2  

E-Print Network [OSTI]

Strong two-photon absorption (TPA) in monolayer MoS2 is demonstrated in contrast to saturable absorption (SA) in multilayer MoS2 under the excitation of femtosecond laser pulses in the near infrared region. MoS2 in the forms of monolayer single crystal and multilayer triangular islands are grown on either quartz or SiO2/Si by employing the seeding method through chemistry vapor deposition. The nonlinear transmission measurements reveal that monolayer MoS2 possesses a giant nonsaturation TPA coefficient, larger than that of conventional semiconductors. As a result of TPA, two-photon pumped frequency up-converted luminescence is observed directly in the monolayer MoS2. For the multilayer MoS2, the SA response is demonstrated with the ratio of the excited-state absorption cross section to ground-state cross section of 0.18. In addition, the laser damage threshold of the monolayer MoS2 is 97 GW/cm2, larger than that of the multilayer MoS2 of 78 GW/cm2.

Li, Yuanxin; Zhang, Saifeng; Zhang, Xiaoyan; Feng, Yanyan; Wang, Kangpeng; Zhang, Long; Wang, Jun

2015-01-01T23:59:59.000Z

393

Processing and characterization of nanocrystalline molybdenum disilicide (MoSi{sub 2}) consolidated by hot isostatic pressing (HIP)  

SciTech Connect (OSTI)

This work studied the effect nanocrystalline processing may have on mechanical properties of MoSi{sub 2} and the ease with which MoSi{sub 2} powder can be processed into a bulk shape. (MoSi{sub 2} presently is limited by poor strength above 1000 C and brittleness below DBTT.) This work studied cold and hot isostatic pressing (CIP, HIP). The attrited, CIPed, and HIPed samples were characterized by chemical analysis, XRD, SEM, microhardness, optical microscopy, and quantitative metallography (porosity, density). Fracture toughness of the nanocrystalline MoSi{sub 2} was found to be a factor of two higher than conventional MoSi{sub 2} and the hardness of 1500 C-HIPed compacts were higher, as well. Modulus test showed the calculated elastic constants to be higher than the original Cerac material.

Haji-Mahmood, M.S.

1995-02-10T23:59:59.000Z

394

Single-layer MoS{sub 2} roughness and sliding friction quenching by interaction with atomically flat substrates  

SciTech Connect (OSTI)

We experimentally study the surface roughness and the lateral friction force in single-layer MoS{sub 2} crystals deposited on different substrates: SiO{sub 2}, mica, and hexagonal boron nitride (h-BN). Roughness and sliding friction measurements are performed by atomic force microscopy. We find a strong dependence of the MoS{sub 2} roughness on the underlying substrate material, being h-BN the substrate which better preserves the flatness of the MoS{sub 2} crystal. The lateral friction also lowers as the roughness decreases, and attains its lowest value for MoS{sub 2} flakes on h-BN substrates. However, it is still higher than for the surface of a bulk MoS{sub 2} crystal, which we attribute to the deformation of the flake due to competing tip-to-flake and flake-to-substrate interactions.

Quereda, J. [Departamento de Física de la Materia Condensada, Universidad Autónoma de Madrid, Madrid E-28049 (Spain); Castellanos-Gomez, A. [Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft (Netherlands); Agraït, N. [Departamento de Física de la Materia Condensada, Universidad Autónoma de Madrid, Madrid E-28049 (Spain); Instituto Madrileño de Estudios Avanzados en Nanociencia, IMDEA-Nanociencia, E-28049 Madrid (Spain); Instituto de Ciencia de Materiales Nicolás Cabrera, Campus de Cantoblanco, E-28049 Madrid (Spain); Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, E-28049 Madrid (Spain); Rubio-Bollinger, G., E-mail: gabino.rubio@uam.es [Departamento de Física de la Materia Condensada, Universidad Autónoma de Madrid, Madrid E-28049 (Spain); Instituto de Ciencia de Materiales Nicolás Cabrera, Campus de Cantoblanco, E-28049 Madrid (Spain); Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, E-28049 Madrid (Spain)

2014-08-04T23:59:59.000Z

395

High blue-near ultraviolet photodiode response of vertically stacked graphene-MoS{sub 2}-metal heterostructures  

SciTech Connect (OSTI)

We present a study on the photodiode response of vertically stacked graphene/MoS{sub 2}/metal heterostructures in which MoS{sub 2} layers are doped with various plasma species. In comparison with undoped heterostructures, such doped ones exhibit significantly improved quantum efficiencies in both photovoltaic and photoconductive modes. This indicates that plasma-doping-induced built-in potentials play an important role in photocurrent generation. As compared to indium-tin-oxide/ MoS{sub 2}/metal structures, the presented graphene/MoS{sub 2}/metal heterostructures exhibit greatly enhanced quantum efficiencies in the blue-near ultraviolet region, which is attributed to the low density of recombination centers at graphene/MoS{sub 2} heterojunctions. This work advances the knowledge for making photo-response devices based on layered materials.

Wi, Sungjin; Chen, Mikai; Nam, Hongsuk; Liu, Amy C.; Meyhofer, Edgar; Liang, Xiaogan, E-mail: xiaoganl@umich.edu [Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109 (United States)

2014-06-09T23:59:59.000Z

396

Incremental Development for Automotive Software in AutoMoDe Andreas Bauer1  

E-Print Network [OSTI]

Incremental Development for Automotive Software in AutoMoDe Andreas Bauer1 Jan Romberg1 Bernhard Validas AG 3 ETAS GmbH 4 PMSF IT Consulting 5 Robert Bosch GmbH Abstract Automotive software development. To facilitate the design and evolution of heterogeneous automotive software, suitable views for each level

Braun, Peter

397

Standards as InterdependentArtifacts: the Case of the Internet Mo-Han Hsieh  

E-Print Network [OSTI]

Standards as InterdependentArtifacts: the Case of the Internet by Mo-Han Hsieh B.S. Civil Systems Chair, Engineer ystems Division Education Committee #12;1 #12;Standards as Interdependent in Engineering Systems ABSTRACT This thesis has explored a new idea: viewing standards as interdependent

de Weck, Olivier L.

398

Synthesis Gas Conversion to Aliphatic Alcohols: Study of MoS2 catalytic systems  

E-Print Network [OSTI]

by sulfidation of ammonium thiomolybate and acetate salts of co-promoters. Several catalyst formulations were prepared by calcination, followed by doping with alkali promoters. Solid state modifications were made in some cases to dilute the active MoS2 material...

Baksh, Faisal

2010-04-19T23:59:59.000Z

399

Investigation of Double Beta Decay of 100Mo to Excited States of 100Ru  

SciTech Connect (OSTI)

Double beta decay of 100Mo to the excited states of daughter nuclei has been studied using a 600 cm3 low-background HPGe detector and an external source consisting of 2588 g of 97.5% enriched metallic 100Mo, which was formerly inside the NEMO-3 detector and used for the NEMO-3 measurements of 100Mo. The half-life for the two-neutrino double beta decay of 100Mo to the excited View the MathML source state in 100Ru is measured to be T1/2=[7.5±0.6(stat)±0.6(syst)]·1020 yr. For other (0?+2?) transitions to the View the MathML source, View the MathML source, View the MathML source, View the MathML source and View the MathML source levels in 100Ru, limits are obtained at the level of ~(0.25–1.1)·1022 yr.

A. J. Caffrey; The NEMO-3 Collaboration

2014-05-01T23:59:59.000Z

400

Spectroscopy of low energy solar neutrinos by MOON -Mo Observatory Of Neutrinos-  

E-Print Network [OSTI]

Spectroscopy of low energy solar neutrinos by MOON -Mo Observatory Of Neutrinos- R. Hazamaa , P Be solar 's. The present status of MOON for the low energy solar experiment is briefly discussed the pp solar flux with good accuracy. 1. INTRODUCTION Realtime studies of the high-energy component of 8

Washington at Seattle, University of

Note: This page contains sample records for the topic "ia mo ar" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Statistical Mechanics, CHEM 6481, Fall MWF 10:05-10:55am, MoSE 1224  

E-Print Network [OSTI]

Statistical Mechanics, CHEM 6481, Fall MWF 10:05-10:55am, MoSE 1224 Course website: T" are considered background material. Required Text: "Introduction to Modern Statistical Mechanics," David Chandler (Oxford, New York, 1982) Recommended Text: "Statistical Mechanics," Donald McQuarrie (HarperCollins, New

Sherrill, David

402

Rejection of randomly coinciding events in ZnMoO$_4$ scintillating bolometers  

E-Print Network [OSTI]

Random coincidence of events (particularly from two neutrino double beta decay) could be one of the main sources of background in the search for neutrinoless double beta decay with cryogenic bolometers due to their poor time resolution. Pulse-shape discrimination by using front edge analysis, mean-time and $\\chi^2$ methods was applied to discriminate randomly coinciding events in ZnMoO$_4$ cryogenic scintillating bolometers. These events can be effectively rejected at the level of 99% by the analysis of the heat signals with rise-time of about 14 ms and signal-to-noise ratio of 900, and at the level of 92% by the analysis of the light signals with rise-time of about 3 ms and signal-to-noise ratio of 30, under the requirement to detect 95% of single events. These rejection efficiencies are compatible with extremely low background levels in the region of interest of neutrinoless double beta decay of $^{100}$Mo for enriched ZnMoO$_4$ detectors, of the order of $10^{-4}$ counts/(y keV kg). Pulse-shape parameters have been chosen on the basis of the performance of a real massive ZnMoO$_4$ scintillating bolometer. Importance of the signal-to-noise ratio, correct finding of the signal start and choice of an appropriate sampling frequency are discussed.

D. M. Chernyak; F. A. Danevich; A. Giuliani; M. Mancuso; C. Nones; E. Olivieri; M. Tenconi; V. I. Tretyak

2014-04-04T23:59:59.000Z

403

TURBO EQUALIZATIONWITH AN UNKNOWN CHANNEL SeongwookSong', Andrew C. Singer2,Koeng-MoSun?  

E-Print Network [OSTI]

TURBO EQUALIZATIONWITH AN UNKNOWN CHANNEL SeongwookSong', Andrew C. Singer2,Koeng-MoSun? l t 2Univ the method of turbo equalization originally de- veloped by Douillard, et al. [3]. In its original form, turbo and without training data. The resultingjoint channeland data estimator is shown to outperform standard turbo

Singer, Andrew C

404

On the Higher-Order MoM-PO Electromagnetic Modeling of Vehicles  

E-Print Network [OSTI]

vehicles (cars, airplanes, helicopters, spacecraft, etc.). From the electromagnetic point of view and accurate higher-order, large-domain hybrid computational technique based on the method of moments (Mo the efficiency and accuracy of the hybrid higher-order computational technique and its advantages over

Notaros, Branislav M.

405

ZnMoO4: a promising bolometer for neutrinoless double beta decay searches  

E-Print Network [OSTI]

We investigate the performances of two ZnMoO4 scintillating crystals operated as bolometers, in view of a next generation experiment to search the neutrinoless double beta decay of Mo-100. We present the results of the alpha vs beta/gamma discrimination, obtained through the scintillation light as well as through the study of the shape of the thermal signal alone. The discrimination capability obtained at the 2615 keV line of Tl-208 is 8 sigma, using the heat-light scatter plot, while it exceeds 20 sigma using the shape of the thermal pulse alone. The achieved FWHM energy resolution ranges from 2.4 keV (at 238 keV) to 5.7 keV (at 2615 keV). The internal radioactive contaminations of the ZnMoO4 crystals were evaluated through a 407 hours background measurement. The obtained limit is < 32 microBq/kg for Th-228 and Ra-226. These values were used for a Monte Carlo simulation aimed at evaluating the achievable background level of a possible, future array of enriched ZnMoO4 crystals.

J. W. Beeman; F. Bellini; S. Capelli; L. Cardani; N. Casali; I. Dafinei; S. Di Domizio; F. Ferroni; E. N. Galashov; L. Gironi; F. Orio; L. Pattavina; G. Pessina; G. Piperno; S. Pirro; V. N. Shlegel; Ya. V. Vasilyev; C. Tomei; M. Vignati

2012-02-01T23:59:59.000Z

406

EIS-0475: Disposition of the Bannister Federal Complex, Kansas City, MO  

Broader source: Energy.gov [DOE]

NNSA/DOE announces its intent to prepare an EIS for the disposition of the Bannister Federal Complex, Kansas City, MO. NNSA previously decided in a separate NEPA review (EA-1592) to relocate its operations from the Bannister Federal Complex to a newly constructed industrial campus eight miles from the current location.

407

TheElectronMicroscopyCore(EMC) UniversityofMissouriColumbia,MO65211  

E-Print Network [OSTI]

TheElectronMicroscopyCore(EMC) UniversityofMissouriColumbia,MO65211 The. The EMC houses two field emission SEM's, a Hitachi cold-field SEM (S-4700) and a FEI thermal FE SEM imaging and chemical analysis from their SEM/EDS systems. AdditionalSupportby: FormoreInformationortoregistergoto:http://www.emc

Noble, James S.

408

Hole Selective MoOx Contact for Silicon Solar Cells Corsin Battaglia,,,  

E-Print Network [OSTI]

Hole Selective MoOx Contact for Silicon Solar Cells Corsin Battaglia,,, Xingtian Yin,,,§, Maxwell, University of California, Berkeley, California 94720, United States Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States § Electronic Materials Research

Javey, Ali

409

This is MoFo. Scientific/Technical Patent Analysts/Agents  

E-Print Network [OSTI]

This is MoFo. Scientific/Technical Patent Analysts/Agents (Los Angeles, CA; McLean, VA; Palo Alto level patent analysts/agents for our Los Angeles, Palo Alto, San Diego and San Francisco offices of business strategies. Patent analysts/agents participate in domestic and foreign patent prosecution

Straight, Aaron

410

2008 IEEE Swarm Intelligence Symposium St. Louis MO USA, September 21-23, 2008  

E-Print Network [OSTI]

2008 IEEE Swarm Intelligence Symposium St. Louis MO USA, September 21-23, 2008 Roach Infestation of the PSO algorithm, entitled Roach Infestation Optimization (RIO), that is inspired by recent discoveries discoveries in the behavior of cockroaches are the inspiration for our proposed algorithm, Roach Infestation

Havens, Timothy

411

Microstructural Analysis of Irradiated U-Mo Fuel Plates: Recent Results  

SciTech Connect (OSTI)

Microstructural characterization of irradiated dispersion and monolithic RERTR fuel plates using scanning electron microscopy (SEM) is being performed in the Electron Microscopy Laboratory at the Idaho National Laboratory. The SEM analysis of samples from U-Mo dispersion fuel plates focuses primarily on the behavior of the Si that has been added to the Al matrix to improve the irradiation performance of the fuel plate and on the overall behavior of fission gases (e.g., Xe and Kr) that develop as bubbles in the fuel microstructure. For monolithic fuel plates, microstructural features of interest, include those found in the U-Mo foil and at the U-Mo/Zr and Zr/6061 Al cladding interfaces. For both dispersion and monolithic fuel plates, samples have been produced using an SEM equipped with a Focused Ion Beam (FIB). These samples are of very high quality and can be used to uncover some very unique microstructural features that are typically not observed when characterizing samples produced using more conventional techniques. Overall, for the dispersion fuel plates with matrices that contained Si, narrower fuel/matrix interaction layers are typically observed compared to the fuel plates with pure Al matrix, and for the monolithic fuel plates microstructural features have been observed in the U-10Mo foil that are similar to what have been observed in the fuel particles found in U-Mo dispersion fuels. Most recently, more prototypic monolithic fuel samples have been characterized and this paper describes the microstructures that have been observed in these samples.

D. D. Keiser, Jr.; J. Jue; B. D. Miller; J. Gan; A. B. Robinson; P. V. Medvedev

2012-03-01T23:59:59.000Z

412

Novel Processing of mo-si-b Intermetallics for improved efficiency of power systems  

SciTech Connect (OSTI)

Multiphase composite alloys based on the Mo-Si-B system are candidate materials for ultra-high temperature applications. In non load-bearing applications such as thermal barrier coatings or heat exchangers in fossil fuel burners, these materials may be ideally suited. Alloys based on the Mo{sub 5}Si{sub 3}B{sub x} phase (Tl phase) possess excellent oxidation resistance to at least 1600 C in synthetic air atmospheres. However, the ability of Tl-based alloys to resist aggressive combustion environments has not yet been determined. The present work seeks to investigate the resistance of these Mo-Si-B alloys to simulated combustion atmospheres. Material was pre-alloyed by combustion synthesis, and samples for testing were prepared by classic powder metallurgical processing techniques. Precursor material synthesized by self-heating-synthesis was sintered to densities exceeding 98% in an argon atmosphere at 1800 C. The approximate phase assemblage of the material was 57% Tl, 29% MoB, 14% MoSi{sub 2} (wt%). The alloy was oxidized from 1000-1100 C in flowing air containing water vapor at 18 Torr. At 1000 C the material achieved a steady state mass loss, and at 1100 C the material undergoes a steady state mass gain. The oxidation rate of these alloys in this temperature regime was accelerated by the presence of water vapor compared to oxidation in dry air. The results of microstructural analysis of the tested alloys will be discussed. Techniques and preliminary results for fabricating near-net-shaped parts will also be presented.

M.J. Kramer; O. Degirmen; A.J. Thom; M. Akinc

2004-09-30T23:59:59.000Z

413

Modeling of Interaction Layer Growth Between U-Mo Particles and an Al Matrix  

SciTech Connect (OSTI)

Interaction layer growth between U-Mo alloy fuel particles and Al in a dispersion fuel is a concern due to the volume expansion and other unfavorable irradiation behavior of the interaction product. To reduce interaction layer (IL) growth, a small amount of Si is added to the Al. As a result, IL growth is affected by the Si content in the Al matrix. In order to predict IL growth during fabrication and irradiation, empirical models were developed. For IL growth prediction during fabrication and any follow-on heating process before irradiation, out-of-pile heating test data were used to develop kinetic correlations. Two out-of-pile correlations, one for the pure Al matrix and the other for the Al matrix with Si addition, respectively, were developed, which are Arrhenius equations that include temperature and time. For IL growth predictions during irradiation, the out-of-pile correlations were modified to include a fission-rate term to consider fission enhanced diffusion, and multiplication factors to incorporate the Si addition effect and the effect of the Mo content. The in-pile correlation is applicable for a pure Al matrix and an Al matrix with the Si content up to 8 wt%, for fuel temperatures up to 200 degrees C, and for Mo content in the range of 6 – 10wt%. In order to cover these ranges, in-pile data were included in modeling from various tests, such as the US RERTR-4, -5, -6, -7 and -9 tests and Korea’s KOMO-4 test, that were designed to systematically examine the effects of the fission rate, temperature, Si content in Al matrix, and Mo content in U-Mo particles. A model converting the IL thickness to the IL volume fraction in the meat was also developed.

Yeon Soo Kim; G. L. Hofman; Ho Jin Ryu; Jong Man Park; A. B. Robinson; D. M. Wachs

2013-12-01T23:59:59.000Z

414

E-Print Network 3.0 - adaptive response ar Sample Search Results  

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

of adaptation could approximate the ARs of P-cells on a single-trial basis in response to a richer stimulus... and color-sensitive pathway) showed response adaptation with...

415

An Application of Augmented Reality (AR) in the Teaching of an Arc Welding Robot  

E-Print Network [OSTI]

Augmented Reality (AR) is an emerging technology that utilizes computer vision methods to overlay virtual objects onto the real world scene so as to make them appear to co-exist with the real objects. Its main objective ...

Chong, J. W. S.

416

arXiv:hep-ph/0301023v321Feb2003 SCIPP 02/37  

E-Print Network [OSTI]

arXiv:hep-ph/0301023v321Feb2003 UCD-02-18 SCIPP 02/37 IUHEX-202 December, 2002 hep-ph/0301023 Higgs-energy supersymmetry . . . . . . . . . . . . . . . . 22 5.1 MSSM Higgs sector at tree level

California at Santa Cruz, University of

417

Apprentice Researchers The Apprentice Researchers (AR) program was awarded supplemental funding by NSF's EHR  

E-Print Network [OSTI]

Apprentice Researchers The Apprentice Researchers (AR) program was awarded supplemental funding apprentices acquire scientific knowledge and lab skills while experiencing what real research in hopes to their peers, family, and mentors. Totals -Summers 1991 to 2008 Total #Apprentices % Apprentices All

Bigelow, Stephen

418

The Navigation and Control technology inside the AR.Drone micro UAV  

E-Print Network [OSTI]

) for the mass market of videos games and home entertainment. The project was publicly presented at the 2010 reality (AR), video games, and interactivity. As is discussed in this article, this landmarking project

419

E-Print Network 3.0 - ar gas mixture Sample Search Results  

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

Search Powered by Explorit Topic List Advanced Search Sample search results for: ar gas mixture Page: << < 1 2 3 4 5 > >> 1 A redetermination of the isotopic abundances of...

420

E-Print Network 3.0 - angular correlations 31ar Sample Search...  

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

Sample search results for: angular correlations 31ar Page: << < 1 2 3 4 5 > >> 1 Low Energy Nuclear and Solid State Physics 1a). BetaGamma Angular Correlations in Au 193 and...

Note: This page contains sample records for the topic "ia mo ar" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

E-Print Network 3.0 - ar-rich source gas Sample Search Results  

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

gas mixture containing 1%CH4... - and Ar-rich plasmas and, as such, a broader range of process parameters investigated. The reported values... , irrespective of the choice of...

422

E-Print Network 3.0 - ar em tomografia Sample Search Results  

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

tomografia Search Powered by Explorit Topic List Advanced Search Sample search results for: ar em tomografia Page: << < 1 2 3 4 5 > >> 1 0.5setgray00.5setgray1 Determinao de...

423

Rovibrational spectroscopy of ArCO van der Waals complex  

SciTech Connect (OSTI)

The information that can be obtained from the high resolution rovibrational spectra of small molecular clusters is very useful for determining intermolecular potentials and the effects of intermolecular interactions on intramolecular bonds. Recently, such spectra have been obtained via absorption measurements using F-center, frequency difference and diode laser sources. Because F-center and frequency difference lasers operate best in the 2-4 ..mu..m region, studies using these laser sources have involved high frequency vibrational modes (H-X, X-C,F,Cl,Br) or overtones. Although diode lasers cover a much broader spectral range (3-20 ..mu..m), they are less convenient to use for doing survey spectroscopy. We have developed several new techniques which improve the sensitivity and convenience of absorption measurements using diode lasers for the study of molecular clusters in supersonic expansions. Here we describe these techniques and their application for the measurement of the rovibrational spectra of ArCO near 5 ..mu..m. 11 refs., 4 figs., 1 tab.

Campbell, E.J.; De Piante Johnston, A.; Buelow, S.J.

1987-01-01T23:59:59.000Z

424

STRUCTURE OF PRESSURE PULSES IN LIQUIDS WITH GAS BUBBLES N.V. Malykh, I.A. 0G0R0DNIK0V  

E-Print Network [OSTI]

are predominant. This leads to the sound speed dispersion and determines either the short pulse structure oriSTRUCTURE OF PRESSURE PULSES IN LIQUIDS WITH GAS BUBBLES N.V. Malykh, I.A. 0G0R0DNIK0V Institute. I.-INTRODUCTION - The main specific feature of a liquide with gas bubbles is the great difference

Paris-Sud XI, Université de

425

EXCELLENTIA CoLumbIA ENgINEErINg26 en million Americans suffer from osteoporosis, a gradual weakening of the  

E-Print Network [OSTI]

HEALTH EXCELLENTIA CoLumbIA ENgINEErINg26 T en million Americans suffer from osteoporosis Laboratory, is try- ing to figure out how to prevent and treat osteoporosis from both engineering analysis of osteoporosis. Guo and his team also plan to use their knowledge to better understand osteoporosis and bone loss

Hone, James

426

EXCELLENTIA CoLumbIA ENgINEErINg22 eople suffering from brain diseases and conditions ranging from traumatic brain  

E-Print Network [OSTI]

HEALTH EXCELLENTIA CoLumbIA ENgINEErINg22 P eople suffering from brain diseases and conditions ranging from traumatic brain injury to brain cancer to progressive brain disorders could be helped if therapeu- tic drugs could be easily delivered to the affected areas. The blood-brain barrier (BBB

Hone, James

427

Cavitation in elastomeric solids: I--A defect-growth theory Oscar Lopez-Pamies a,, Martin I. Idiart b,c  

E-Print Network [OSTI]

Cavitation in elastomeric solids: I--A defect-growth theory Oscar Lopez-Pamies a,�, Marti´n I. The occurrence of such instabilities, commonly referred to as cavitation, can be attributed to the growth of pre-existing defects into finite sizes. This paper introduces a new theory to study the phenomenon of cavitation

Nakamura, Toshio

428

I.A. Karimi and Rajagopalan Srinivasan (Editors), Proceedings of the 11th International Symposium on Process Systems Engineering, 15-19 July 2012, Singapore.  

E-Print Network [OSTI]

I.A. Karimi and Rajagopalan Srinivasan (Editors), Proceedings of the 11th International Symposium for a hydrodesulfurization HDS plant of a petroleum refinery with regards to hydrogen consumption optimization. The resulting be looked for. Potential application to global refinery H2 network is also discussed. Keywords: self

Skogestad, Sigurd

429

First-principles study of the interfacial adhesion between SiO2 and MoSi2 D. E. Jiang1 and Emily A. Carter2  

E-Print Network [OSTI]

the energy efficiency and per- formance of gas turbine engines requires structural materials able to operate on MoSi2, a potential high-temperature coating material for metals. This silica scale protects MoSi2 the potential of MoSi2 as a high-temperature structural material and coating. DOI: 10.1103/PhysRevB.72

Carter, Emily A.

430

Le magn)sme ar)ficiel pour les gaz d'atomes froids Jean Dalibard  

E-Print Network [OSTI]

Le magné)sme ar)ficiel pour les gaz d'atomes froids Jean Dalibard Année 2013-14 Chaire Atomes et rayonnement Magné8sme ar8ficiel et interac8ons : condensats en rota8on #12;Magné8sme dans une assemblée de par8cule en interac8on

Dalibard, Jean

431

The science case for 37Ar as a monitor for underground nuclear explosions  

SciTech Connect (OSTI)

A new calculation of the production of 37Ar from nuclear explosion neutron interactions on 40Ca in a suite of common sub-surface materials (rock, etc) is presented. Even in mineral structures that are relatively low in Ca, the resulting 37Ar signature is large enough for detection in cases of venting or gaseous diffusion driven by barometric pumping. Field and laboratory detection strategies and projected sensitivities are presented.

Haas, Derek A.; Orrell, John L.; Bowyer, Ted W.; McIntyre, Justin I.; Miley, Harry S.; Aalseth, Craig E.; Hayes, James C.

2010-06-04T23:59:59.000Z

432

Ion chemistry in H{sub 2}-Ar low temperature plasmas  

SciTech Connect (OSTI)

A rate equation model is devised to study the ion composition of inductively coupled H{sub 2}-Ar plasmas with different H{sub 2}-Ar mixing ratios. The model is applied to calculate the ion densities n{sub i}, the wall loss probability of atomic hydrogen ?{sub H}, and the electron temperature T{sub e}. The calculated n{sub i}'s of Ar{sup +}, H{sup +}, H{sub 2}{sup +}, H{sub 3}{sup +}, and ArH{sup +} are compared with experimental results. Calculations were made for a total gas pressure of 1.0 Pa. The production and loss channels of all ions are presented and discussed in detail. With the production and loss rates, the density dependence of each ion on the plasma parameters is explained. It is shown that the primary ions H{sub 2}{sup +} and Ar{sup +} which are produced by ionization of the background gas by electron collisions are effectively converted into H{sub 3}{sup +} and ArH{sup +}. The high density of ArH{sup +} and Ar{sup +} is attributed to the low loss to the walls compared to hydrogen ions. It is shown that the H{sup +}/H{sub 2}{sup +} density ratio is strongly correlated to the H/H{sub 2} density ratio. The dissociation degree is around 1.7%. From matching the calculated to the measured atomic hydrogen density n{sub H}, the wall loss probability of atomic hydrogen on stainless steel ?{sub H} was determined to be ?{sub H}=0.24. The model results were compared with recently published experimental results. The calculated and experimentally obtained data are in fair agreement.

Sode, M.; Schwarz-Selinger, T.; Jacob, W. [Max-Planck-Institut für Plasmaphysik, EURATOM Association, Boltzmannstraße 2, D-85748 Garching (Germany)] [Max-Planck-Institut für Plasmaphysik, EURATOM Association, Boltzmannstraße 2, D-85748 Garching (Germany)

2013-08-14T23:59:59.000Z

433

Data Packages in Hanford Site's Administrative Record (AR) and Public Information Repository (PIR)  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

In 1989, the Department of Energy joined with the Washington State Department of Ecology and the U.S. Environmental Protection Agency in signing the Hanford Federal Facility Agreement and Consent Order more commonly known as the Tri-Party Agreement (TPA). The TPA outlines legally enforceable milestones for Hanford cleanup over the next several decades. The AR is the body of documents and information that is considered or relied upon to arrive at a final decision for remedial action or hazardous waste management. An AR is established for each operable unit (OU); treatment, storage, or disposal unit (TSD); or Expedited Response Action (ERA) group and will contain all documents having information considered in arriving at a Record of Decision or permit. Documents become part of the AR after they have been designated as an AR by the TPA or after EPA, DOE, or other official parties have identified a document or set of documents for inclusion. Furthermore, AR documents are to be kept in a Public Information Repository (PIR).Thousands of data packages that support the AR documents are available to the public in the Hanford PIR.

434

MoS{sub 2}@ZnO nano-heterojunctions with enhanced photocatalysis and field emission properties  

SciTech Connect (OSTI)

The molybdenum disulfide (MoS{sub 2})@ZnO nano-heterojunctions were successfully fabricated through a facile three-step synthetic process: prefabrication of the ZnO nanoparticles, the synthesis of MoS{sub 2} nanoflowers, and the fabrication of MoS{sub 2}@ZnO heterojunctions, in which ZnO nanoparticles were uniformly self-assembled on the MoS{sub 2} nanoflowers by utilizing polyethyleneimine as a binding agent. The photocatalytic activities of the composite samples were evaluated by monitoring the photodegradation of methylene blue (MB). Compared with pure MoS{sub 2} nanoflowers, the composites show higher adsorption capability in dark and better photocatalytic efficiency due to the increased specific surface area and improved electron-hole pair separation. After irradiation for 100?min, the remaining MB in solution is about 7.3%. Moreover, the MoS{sub 2}@ZnO heterojunctions possess enhanced field emission properties with lower turn-on field of 3.08?V ?m{sup ?1}and lower threshold field of 6.9?V ?m{sup ?1} relative to pure MoS{sub 2} with turn-on field of 3.65?V ?m{sup ?1} and threshold field of 9.03?V ?m{sup ?1}.

Tan, Ying-Hua; Yu, Ke, E-mail: yk5188@263.net; Li, Jin-Zhu; Fu, Hao; Zhu, Zi-Qiang [Key Laboratory of Polar Materials and Devices (Ministry of Education of China), Department of Electronic Engineering, East China Normal University, Shanghai 200241 (China)

2014-08-14T23:59:59.000Z

435

Effect of MoS{sub 2} on hydrogenation storage properties of LiBH{sub 4}  

SciTech Connect (OSTI)

The hydrogen storage properties of LiBH{sub 4} ball milled with 20 wt% MoS{sub 2} have been investigated. It shows that the LiBH{sub 4} doped with MoS{sub 2} exhibits favorable hydrogenation and dehydrogenation properties in terms of decomposition temperature and hydriding/dehydriding reversibility. The sample with MoS{sub 2} starts to release hydrogen at 230 °C and has a decrease of 80 °C in contrast with pristine LiBH{sub 4}. Furthermore, for the second cycle, the LiBH{sub 4} with MoS{sub 2} maintains a reversible hydrogen storage capacity of about 8.0 wt% which is almost identical with the first cycle under 5 MPa at 550 °C. Analyzed by the XRD and the FTIR results, LiBH{sub 4} can be regenerated after re-hydrogenation under a relatively mild condition by adding MoS{sub 2}. The improvement of the hydrogenation and dehydrogenation properties mainly results from the formation of Li{sub 2}S and MoB{sub 2} during ball milling. -- Graphical abstract: Hydrogen absorption curves of LiBH{sub 4} doped with MoS{sub 2} for five cycles at 400 °C. Highlights: • The hydrogen absorption capacity is nearly the same for 5 cycles at 400 °C. • The sample with MoS{sub 2} starts to release hydrogen at 230 °C. • The coexistence of MoB{sub 2} and Li{sub 2}S catalyzes the decomposition of LiBH{sub 4}.

Liang, Dan [College of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao 066004 (China); Han, Shumin, E-mail: hanshm@ysu.edu.cn [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004 (China); College of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao 066004 (China); Wang, Jiasheng [College of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao 066004 (China); Zhang, Wei [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004 (China); College of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao 066004 (China); Zhao, Xin; Zhao, Ziyang [College of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao 066004 (China)

2014-03-15T23:59:59.000Z

436

The University of Iowa College of Engineering Engineering Professional Development  

E-Print Network [OSTI]

Athena GTX Des Moines, IA Caterpillar Mossville, IL Caterpillar Peoria, IL Cerner Kansas City, MO Eaton Rapids, IA Siemens Corporate Research Princeton, NJ Source Allies Des Moines, IA Square D Cedar Rapids

Jacob, Mathews

437

Photoresponse properties of large-area MoS{sub 2} atomic layer synthesized by vapor phase deposition  

SciTech Connect (OSTI)

Photoresponse properties of a large area MoS{sub 2} atomic layer synthesized by vapor phase deposition method without any catalyst are studied. Scanning electron microscopy, atomic force microscopy, Raman spectrum, and photoluminescence spectrum characterizations confirm that the two-dimensional microstructures of MoS{sub 2} atomic layer are of high quality. Photoelectrical results indicate that the as-prepared MoS{sub 2} devices have an excellent sensitivity and a good reproducibility as a photodetector, which is proposed to be ascribed to the potential-assisted charge separation mechanism.

Luo, Siwei; Qi, Xiang, E-mail: xqi@xtu.edu.cn, E-mail: jxzhong@xtu.edu.cn; Ren, Long; Hao, Guolin; Fan, Yinping; Liu, Yundan; Han, Weijia; Zang, Chen; Li, Jun; Zhong, Jianxin, E-mail: xqi@xtu.edu.cn, E-mail: jxzhong@xtu.edu.cn [Hunan Key Laboratory for Micro-Nano Energy Materials and Devices, People's Republic of China Laboratory for Quantum Engineering and Micro-Nano Energy Technology, and Faculty of Materials and Optoelectronic Physics, Xiangtan University, Hunan 411105 (China)

2014-10-28T23:59:59.000Z

438

Sr{sub 2}MgMoO{sub 6??} thin films fabricated using pulsed-laser deposition with high concentrations of oxygen vacancies  

SciTech Connect (OSTI)

We fabricated epitaxial thin films of oxygen-vacant Sr{sub 2}MgMoO{sub 6??} using pulsed laser deposition. The films showed low resistivity of the order of 10{sup ?2} ??cm at 300?K. X-ray diffraction analyses revealed that Mg and Mo ions in the Sr{sub 2}MgMoO{sub 6??} films were considerably disordered, compared to those in bulk Sr{sub 2}MgMoO{sub 6??}. The proportion of oxygen vacancies estimated through hard x-ray photoemission measurements was as large as 0.37, and correlated well with the Mg/Mo ordering.

Shigematsu, K. [Department of Chemistry, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033 (Japan); Chikamatsu, A., E-mail: chikamatsu@chem.s.u-tokyo.ac.jp; Fukumura, T. [Department of Chemistry, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033 (Japan); JST-CREST, Bunkyo-ku, Tokyo 113-0033 (Japan); Toyoda, S. [Department of Materials Science and Engineering, Kyoto University, Yoshida-honmachi, Kyoto 606-8501 (Japan); Ikenaga, E. [JASRI/SPring-8, Mikazuki-cho, Hyogo 679-5198 (Japan); Hasegawa, T. [Department of Chemistry, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033 (Japan); JST-CREST, Bunkyo-ku, Tokyo 113-0033 (Japan); Kanagawa Academy of Science and Technology (KAST), Kawasaki, Kanagawa 213-0012 (Japan)

2014-06-30T23:59:59.000Z

439

Symmetry energy and the isoscaling properties of the fragments in multifragmentation of 40Ca+58Ni, 40Ar+58Ni, and 40Ar+58Fe reactions  

E-Print Network [OSTI]

The symmetry energy and the isoscaling properties of the fragments produced in multifragmentation of 40Ar, 40Ca + 58Fe, 58Ni reactions at 25, 33, 45 and 53 MeV/nucleon were investigated within the framework of a statistical multifragmentation model...

Iglio, Jennifer Ann

2007-09-17T23:59:59.000Z

440

AMoRE: Collaboration for searches for the neutrinoless double-beta decay of the isotope of {sup 100}Mo with the aid of {sup 40}Ca{sup 100}MoO{sub 4} as a cryogenic scintillation detector  

SciTech Connect (OSTI)

The AMoRE (Advanced Mo based Rare process Experiment) Collaboration is planning to employ {sup 40}Ca{sup 100}MoO{sub 4} single crystals as a cryogenic Scintillation detector for studying the neutrinoless double-beta decay of the isotope {sup 100}Mo. A simultaneous readout of phonon and scintillation signals is performed in order to suppress the intrinsic background. The planned sensitivity of the experiment that would employ 100 kg of {sup 40}Ca{sup 100}MoO{sub 4} over five years of data accumulation would be T{sub 1/2}{sup 0{nu}} = 3 Multiplication-Sign 10{sup 26} yr, which corresponds to values of the effective Majorana neutrino mass in the range of Left-Pointing-Angle-Bracket m{sub {nu}} Right-Pointing-Angle-Bracket {approx} 0.02-0.06 eV.

Khanbekov, N. D., E-mail: xanbekov@gmail.com [Institute of Theoretical and Experimental Physics (Russian Federation)

2013-09-15T23:59:59.000Z

Note: This page contains sample records for the topic "ia mo ar" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Structure of Co-Mo/UPSILON-Al/sub 7/O/sub 3/ catalysts and relationship to HDS and hydrogenation activity. [Hydrodesulfurization (HDS)  

SciTech Connect (OSTI)

From Mossbauer spectroscopy studies of catalysts of typical industrial compositions and activity measurements it was shown that catalysts containing the ''Co-Mo-S'' phase have relatively higher hydrodesulfurization (HDS) activities. It was also found that the use of Co in the first impregnation step favored the formation of Co/sub 9/S/sub 8/ (in addition to Co in alumina), while the reverse impregnation order produced mainly the ''Co-Mo-S'' phase. Avoiding Co/sub 3/O/sub 4/ formation in the oxide precursor was important for the formation of the ''Co-Mo-S'' phase and this was achieved by the impregnation of Mo before Co. There was also evidence that when Co was used in the second impregnation step, there was significant Mo, Co interaction. This interaction my produce a CoMo surface phase which is disordered and well dispersed and sulfides to the ''Co-Mo-S'' phase. (JMT)

Bennet, B.A. (Imperial Coll., London, England); Chadwick, D.; Jawahery, A.R.; Breysse, M.; Vrinat, M.

1982-09-01T23:59:59.000Z

442

Improved performance of U-Mo dispersion fuel by Si addition in Al matrix.  

SciTech Connect (OSTI)

The purpose of this report is to collect in one publication and fit together work fragments presented in many conferences in the multi-year time span starting 2002 to the present dealing with the problem of large pore formation in U-Mo/Al dispersion fuel plates first observed in 2002. Hence, this report summarizes the excerpts from papers and reports on how we interpreted the relevant results from out-of-pile and in-pile tests and how this problem was dealt with. This report also provides a refined view to explain in detail and in a quantitative manner the underlying mechanism of the role of silicon in improving the irradiation performance of U-Mo/Al.

Kim, Y S; Hofman, G L [Nuclear Engineering Division

2011-06-01T23:59:59.000Z

443

Oxidation Behavior and Chlorination Treatment to Improve Oxidation Resistance of Nb-Mo-Si-B Alloys  

SciTech Connect (OSTI)

This thesis is written in an alternate format. The thesis is composed of a general introduction, two original manuscripts, and a general conclusion. References cited within each chapter are given at the end of each chapter. The general introduction starts with the driving force behind this research, and gives an overview of previous work on boron doped molybdenum silicides, Nb/Nb{sub 5}Si{sub 3} composites, boron modified niobium silicides and molybdenum niobium silicides. Chapter 2 focuses on the oxidation behavior of Nb-Mo-Si-B alloys. Chapter 3 contains studies on a novel chlorination technique to improve the oxidation resistance of Nb-Mo-Si-B alloys. Chapter 4 summarizes the important results in this study.

Vikas Behrani

2004-12-19T23:59:59.000Z

444

Spectroscopy of Double-Beta and Inverse-Beta Decays from 100Mo for Neutrinos  

E-Print Network [OSTI]

Spectroscopic studies of two beta-rays from 100Mo are shown to be of potential interest for investigating both the Majorana neutrino mass by neutrinoless double beta-decay and low energy solar neutrino's by inverse beta-decay. With a multi-ton 100Mo detector, coincidence studies of correlated beta-beta from neutrinoless double beta-decay, together with the large Q value, permit identification of the neutrino-mass term with a sensitivity of ~ 0.03 eV. Correlation studies of the inverse beta and the successive beta-decay of 100Tc, together with the large capture rates for low energy solar neutrino's, make it possible to detect in realtime individual low energy solar neutrino in the same detector.

H. Ejiri; J. Engel; R. Hazama; P. Krastev; N. Kudomi; R. G. H. Robertson

2000-05-15T23:59:59.000Z

445

Silicon heterojunction solar cell with passivated hole selective MoO{sub x} contact  

SciTech Connect (OSTI)

We explore substoichiometric molybdenum trioxide (MoO{sub x}, x?MoO{sub x}, we observe a substantial gain in photocurrent of 1.9?mA/cm{sup 2} in the ultraviolet and visible part of the solar spectrum, when compared to a p-type amorphous silicon emitter of a traditional silicon heterojunction cell. Our results emphasize the strong potential for oxides as carrier selective heterojunction partners to inorganic semiconductors.

Battaglia, Corsin; Yin, Xingtian; Zheng, Maxwell; Javey, Ali, E-mail: ajavey@eecs.berkeley.edu [Electrical Engineering and Computer Sciences Department, University of California, Berkeley, California 94720 (United States); Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Martín de Nicolás, Silvia; De Wolf, Stefaan; Ballif, Christophe [Photovoltaics and Thin Film Electronics Laboratory, Ecole Polytechnique Fédérale de Lausanne, 2000 Neuchâtel (Switzerland)

2014-03-17T23:59:59.000Z

446

Induced codeposition. 1: An experimental investigation of Ni-Mo alloys  

SciTech Connect (OSTI)

The electrodeposition of nickel-molybdenum alloys was studied on rotating cylinder electrodes. The current density, electrode rotation rate, electrolyte temperature, and species concentrations were shown to influence alloy composition. The mass-transport limiting species were identified for different operating conditions and electrolyte compositions in order to study the rate-limiting steps of induced codeposition. If the concentration of nickel in the electrolyte was much larger than that of molybdate the molybdenum content in the alloy increased with rotation rate. On the other hand, if the concentration of molybdate in the electrolyte was larger than that of nickel the alloy composition was found to be independent of rotation rate. These results were applied to the deposition of compositionally modulated Ni-Mo alloys exhibiting larger periodic variations in Mo concentration than hitherto reported.

Podlaha, E.J.; Landolt, D. [Ecole Polytechnique Federale de Lausanne (Switzerland)

1996-03-01T23:59:59.000Z

447

Phase transitions in K-doped MoO{sub 2}  

SciTech Connect (OSTI)

K{sub 0.05}MoO{sub 2} has been studied by x-ray and neutron diffractometry, electrical resistivity, magnetization, heat capacity, and thermal expansion measurements. The compound displays two phase transitions, a first-order phase transition near room temperature and a second-order transition near 54?K. Below the transition at 54?K, a weak magnetic anomaly is observed and the electrical resistivity is well described by a power-law temperature dependence with exponent near 0.5. The phase transitions in the K-doped MoO{sub 2} compound have been discussed for the first time using neutron diffraction, high resolution thermal expansion, and heat capacity measurements as a function of temperature.

Alves, L. M. S., E-mail: leandro-fisico@hotmail.com; Lima, B. S. de; Santos, C. A. M. dos [Departamento de Engenharia de Materiais, Escola de Engenharia de Lorena-USP, Lorena, São Paulo 12602-810 (Brazil); Rebello, A.; Masunaga, S. H.; Neumeier, J. J. [Department of Physics, Montana State University, P.O. Box 173840, Bozeman, Montana 59717-3840 (United States); Leão, J. B. [NIST Center for Neutron Research, National Institute of Standards and Technology, 100 Bureau Dr. MS 6102, Gaithersburg, Maryland 20899-6102 (United States)

2014-05-28T23:59:59.000Z

448

AutoMoDe - Model-Based Development of Automotive Software  

E-Print Network [OSTI]

This paper describes first results from the AutoMoDe (Automotive Model-Based Development) project. The overall goal of the project is to develop an integrated methodology for model-based development of automotive control software, based on problem-specific design notations with an explicit formal foundation. Based on the existing AutoFOCUS framework, a tool prototype is being developed in order to illustrate and validate the key elements of our approach.

Ziegenbein, Dirk; Freund, Ulrich; Bauer, Andreas; Romberg, Jan; Schatz, Bernhard

2011-01-01T23:59:59.000Z

449

Process-dependent electronic states at Mo/hafnium oxide/Si interfaces  

SciTech Connect (OSTI)

The authors have used low energy electron-excited nanoscale depth-resolved cathodoluminescence spectroscopy (DRCLS) to probe the bulk and interface defect states of ultrathin Mo/HfO{sub 2}/Si with eight different process sequences. After atomic layer deposition of 4 nm HfO{sub 2} on Si and an O{sub 2} post-treatment, they deposited 10 nm Mo using either plasma vapor or electron beam deposition, with or without a subsequent 1000 deg. C N{sub 2} anneal and with or without a forming gas anneal. DRCLS revealed pronounced gap state emissions within the ultrathin films and their interfaces with Mo and Si. There are multiple deep level emissions below the {approx}5.9 eV near band edge, including peak emissions at 3.4, 3.5, and 3.9-4.3 eV that can be associated with HfO{sub 2} oxygen vacancies in different charge states predicted theoretically. In addition, states at 2-2.6 eV that resemble known SiO{sub 2}-related nonbonding oxygen hole centers and E{sup '} (positively charged O vacancy) native defects increase with depth within the 4 nm HfO{sub 2} film, suggesting the formation of a Hf silicate at the HfO{sub 2}/Si interface. No metal-specific interface states at the HfO{sub 2}/Mo interface are evident. Furthermore, different process steps produce large changes in these states and for at least one sequence, a dramatic decrease in both types of defects. The differences between process sequences can be understood in terms of known reactions at HfO{sub 2}-Si interfaces.

Walsh, S.; Fang, L.; Schaeffer, J. K.; Brillson, L. J. [Department of Physics, Ohio State University, Columbus, Ohio 43210 (United States); Technology Solutions Organization, Freescale Semiconductor, Inc., Austin, Texas 78721 (United States); Department of Electrical and Computer Engineering, Department of Physics and Center for Materials Research, Ohio State University, Columbus, Ohio 43210 (United States)

2007-07-15T23:59:59.000Z

450

Continuing investigations for technology assessment of /sup 99/Mo production from LEU (low enriched Uranium) targets  

SciTech Connect (OSTI)

Currently much of the world's supply of /sup 99m/Tc for medical purposes is produced from /sup 99/Mo derived from the fissioning of high enriched uranium (HEU). The need for /sup 99m/Tc is continuing to grow, especially in developing countries, where needs and national priorities call for internal production of /sup 99/Mo. This paper presents the results of our continuing studies on the effects of substituting low enriched Uranium (LEU) for HEU in targets for the production of fission product /sup 99/Mo. Improvements in the electrodeposition of thin films of uranium metal are reported. These improvements continue to increase the appeal for the substitution of LEU metal for HEU oxide films in cylindrical targets. The process is effective for targets fabricated from stainless steel or hastaloy. A cost estimate for setting up the necessary equipment to electrodeposit uranium metal on cylindrical targets is reported. Further investigations on the effect of LEU substitution on processing of these targets are also reported. Substitution of uranium silicides for the uranium-aluminum alloy or uranium aluminide dispersed fuel used in other current target designs will allow the substitution of LEU for HEU in these targets with equivalent /sup 99/Mo-yield per target and no change in target geometries. However, this substitution will require modifications in current processing steps due to (1) the insolubility of uranium silicides in alkaline solutions and (2) the presence of significant quantities of silicate in solution. Results to date suggest that both concerns can be handled and that substitution of LEU for HEU can be achieved.

Vandergrift, G.F.; Kwok, J.D.; Marshall, S.L.; Vissers, D.R.; Matos, J.E.

1987-01-01T23:59:59.000Z

451

First spectroscopic investigation of the 4d transition metal monocarbide MoC  

E-Print Network [OSTI]

C simply fills the 2 orbital. Next in the 4d metal-carbide series is another well studied mol- ecule, RhFirst spectroscopic investigation of the 4d transition metal monocarbide MoC Dale J. Brugh transition metal monocarbides, of which only FeC,1­3 CoC,4,5 and NiC Ref. 6 have been studied in detail

Morse, Michael D.

452

Production and Characterization of Atomized U-Mo Powder by the Rotating Electrode Process  

SciTech Connect (OSTI)

In order to produce feedstock fuel powder for irradiation testing, the Idaho National Laboratory has produced a rotating electrode type atomizer to fabricate uranium-molybdenum alloy fuel. Operating with the appropriate parameters, this laboratory-scale atomizer produces fuel in the desired size range for the RERTR dispersion experiments. Analysis of the powder shows a homogenous, rapidly solidified microstructure with fine equiaxed grains. This powder has been used to produce irradiation experiments to further test adjusted matrix U-Mo dispersion fuel.

C.R. Clark; B.R. Muntifering; J.F. Jue

2007-09-01T23:59:59.000Z

453

Co-Rolled U10Mo/Zirconium-Barrier-Layer Monolithic Fuel Foil Fabrication Process  

SciTech Connect (OSTI)

Integral to the current UMo fuel foil processing scheme being developed at Idaho National Laboratory (INL) is the incorporation of a zirconium barrier layer for the purpose of controlling UMo-Al interdiffusion at the fuel-meat/cladding interface. A hot “co-rolling” process is employed to establish a ~25-µm-thick zirconium barrier layer on each face of the ~0.3-mm-thick U10Mo fuel foil.

G. A. Moore; M. C. Marshall

2010-01-01T23:59:59.000Z

454

THE TIP OF THE RED GIANT BRANCH DISTANCES TO TYPE Ia SUPERNOVA HOST GALAXIES. II. M66 AND M96 IN THE LEO I GROUP  

SciTech Connect (OSTI)

M66 and M96 in the Leo I Group are nearby spiral galaxies hosting Type Ia supernovae (SNe Ia). We estimate the distances to these galaxies from the luminosity of the tip of the red giant branch (TRGB). We obtain VI photometry of resolved stars in these galaxies from F555W and F814W images in the Hubble Space Telescope archive. From the luminosity function of these red giants, we find the TRGB I-band magnitude to be I{sub TRGB} = 26.20 {+-} 0.03 for M66 and 26.21 {+-} 0.03 for M96. These values yield distance modulus (m - M){sub 0} = 30.12 {+-} 0.03(random) {+-} 0.12(systematic) for M66 and (m - M){sub 0} = 30.15 {+-} 0.03(random) {+-} 0.12(systematic) for M96. These results show that they are indeed the members of the same group. With these results we derive absolute maximum magnitudes of two SNe (SN 1989B in M66 and SN 1998bu in M96). V-band magnitudes of these SNe Ia are {approx}0.2 mag fainter than SN 2011fe in M101, one of the nearest recent SNe Ia. We also derive near-infrared magnitudes for SN 1998bu. Optical magnitudes of three SNe Ia (SN 1989B, SN 1998bu, and SN 2011fe) based on TRGB analysis yield a Hubble constant, H{sub 0} = 68.4 {+-} 2.6(random) {+-} 3.7(systematic) km s{sup -1} Mpc{sup -1}. This value is similar to the values derived from recent WMAP9 results, H{sub 0} = 69.32 {+-} 0.80 km s{sup -1} Mpc{sup -1}, and from Planck results, H{sub 0} = 67.3 {+-} 1.2 km s{sup -1} Mpc{sup -1}, but smaller than other recent determinations based on Cepheid calibration for SNe Ia luminosity, H{sub 0} = 74 {+-} 3 km s{sup -1} Mpc{sup -1}.

Lee, Myung Gyoon; Jang, In Sung, E-mail: mglee@astro.snu.ac.kr, E-mail: isjang@astro.snu.ac.kr [Astronomy Program, Department of Physics and Astronomy, Seoul National University, Gwanak-gu, Seoul 151-742 (Korea, Republic of)

2013-08-10T23:59:59.000Z

455

Performance of ZnMoO4 crystal as cryogenic scintillating bolometer to search for double beta decay of molybdenum  

E-Print Network [OSTI]

Zinc molybdate (ZnMoO4) single crystals were grown for the first time by the Czochralski method and their luminescence was measured under X ray excitation in the temperature range 85-400 K. Properties of ZnMoO4 crystal as cryogenic low temperature scintillator were checked for the first time. Radioactive contamination of the ZnMoO4 crystal was estimated as <0.3 mBq/kg (228-Th) and 8 mBq/kg (226-Ra). Thanks to the simultaneous measurement of the scintillation light and the phonon signal, the alpha particles can be discriminated from the gamma/beta interactions, making this compound extremely promising for the search of neutrinoless Double Beta Decay of 100-Mo. We also report on the ability to discriminate the alpha-induced background without the light measurement, thanks to a different shape of the thermal signal that characterizes gamma/beta and alpha particle interactions.

L. Gironi; C. Arnaboldi; J. W. Beeman; O. Cremonesi; F. A. Danevich; V. Ya. Degoda; L. I. Ivleva; L. L. Nagornaya; M. Pavan; G. Pessina; S. Pirro; V. I. Tretyak; I. A. Tupitsyna

2010-10-01T23:59:59.000Z

456

High yield production of inorganic graphene-like materials (MoS?, WS?, BN) through liquid exfoliation testing key parameters  

E-Print Network [OSTI]

Inorganic graphene-like materials such as molybdenum disulfide (MoS?), tungsten sulfide (WS?), and boron nitride (BN) are known to have electronic properties. When exfoliated into layers and casted onto carbon nanofilms, ...

Pu, Fei, S.B. Massachusetts Institute of Technology

2012-01-01T23:59:59.000Z

457

Highly Z- and Enantioselective Ring-Opening/Cross-Metathesis Reactions Catalyzed by Stereogenic-at-Mo Adamantylimido Complexes  

E-Print Network [OSTI]

The first highly Z- and enantioselective class of ring-opening/cross-metathesis reactions is presented. Transformations are promoted in the presence of <2 mol % of chiral stereogenic-at-Mo monoaryloxide complexes bearing ...

Ibrahem, Ismail

458

LEXICAL DECISION IN A PHONOLOGICALLY SHALLOW ORTHOGRAPHY* G Lukatela+, Do Popadic+, P. Ognjenovic+, and Mo To Turvey++  

E-Print Network [OSTI]

+, and Mo To Turvey++ Abstracto The Serbo-Croatian language is written in two alphabets, Roman and Cyrillic shallow writing systems of Serbo-Croatian, lex ical decision proceeds with reference to the phonology

459

CO and NO Adsorption and Dissociation at the -Mo2C(0001) Surface: A Density Functional Theory Study  

E-Print Network [OSTI]

. Introduction Transition-metal carbides have attracted great interest because of their exciting physical as well as thermal conductivity.3 In addition, -molybdenum carbide ( -Mo2C)-based catalysts exhibit

460

Two photon absorption and its saturation of WS2 and MoS2 monolayer and few-layer films  

E-Print Network [OSTI]

The optical nonlinearity of WS2, MoS2 monolayer and few-layer films was investigated using the Z-scan technique with femtosecond pulses from the visible to the near infrared. The dependence of nonlinear absorption of the WS2 and MoS2 films on layer number and excitation wavelength was studied systematically. WS2 with 1~3 layers exhibits a giant two-photon absorption (TPA) coefficient. Saturation of TPA for WS2 with 1~3 layers and MoS2 with 25~27 layers was observed. The giant nonlinearity of WS2 and MoS2 is attributed to two dimensional confinement, a giant exciton effect and the band edge resonance of TPA.

Zhang, Saifeng; McEvoy, Niall; O'Brien, Maria; Winters, Sinéad; Berner, Nina C; Yim, Chanyoung; Zhang, Xiaoyan; Chen, Zhanghai; Zhang, Long; Duesberg, Georg S; Wang, Jun

2015-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "ia mo ar" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Evolution of collectivity along the N=Z line: The {sup 84}Mo nucleus  

SciTech Connect (OSTI)

The reaction {sup 58}Ni({sup 28}Si,2n{gamma}) at 90 MeV incident energy has been used to populate the N=Z nucleus {sup 84}Mo. The GASP array was used together with the ISIS Silicon ball, which allowed a subtraction of the charged particle channels in the {gamma}-{gamma} coincidences. The only known transition 2{sub 1}{sup +}{r_arrow}0{sub 1}{sup +} of 443.8 keV in {sup 84}Mo has been found in coincidence with a {gamma} ray of 673.5{plus_minus}0.4 keV which was assigned as the second (4{sub 1}{sup +}{r_arrow}2{sub 1}{sup +}) yrast transition. The behavior of the resulting yrast line indicates that {sup 84}Mo is a transitional nucleus. The correlation between the excitation energies of the 2{sub 1}{sup +} and 4{sub 1}{sup +} levels of the N=Z nuclei reveals a systematic deviation from the average behavior defined by all collective even-even nuclei. {copyright} {ital 1997} {ital The American Physical Society}

Bucurescu, D.; Ur, C.A.; Marginean, N.; Ionescu-Bujor, M.; Iordachescu, A.; Petrache, C.M. [Horia Hulubei National Institute of Physics and Nuclear Engineering, Bucharest (Romania)] [Horia Hulubei National Institute of Physics and Nuclear Engineering, Bucharest (Romania); Ur, C.A; Bazzacco, D.; Lunardi, S.; Petrache, C.M.; Brandolini, F.; Falconi, G.; Lenzi, S.M.; Venturelli, R. [Dipartimento di Fisica dellUniversita and INFN, Sezione di Padova, Padova (Italy)] [Dipartimento di Fisica dellUniversita and INFN, Sezione di Padova, Padova (Italy); Napoli, D.R.; de Angelis, G.; Gadea, A.; Foltescu, D.; Farnea, E.; Podolyak, Zs.; De Poli, M. [INFN, Laboratori Nazionali di Legnaro, Legnaro (Italy)] [INFN, Laboratori Nazionali di Legnaro, Legnaro (Italy); Rao, M.N. [Universidade de Sao Paolo, Sao Paolo, Brasil (Brazil)] [Universidade de Sao Paolo, Sao Paolo, Brasil (Brazil)

1997-11-01T23:59:59.000Z

462

Rejection of randomly coinciding events in ZnMoO$_4$ scintillating bolometers  

E-Print Network [OSTI]

Random coincidence of events (particularly from two neutrino double beta decay) could be one of the main sources of background in the search for neutrinoless double beta decay with cryogenic bolometers due to their poor time resolution. Pulse-shape discrimination by using front edge analysis, mean-time and $\\chi^2$ methods was applied to discriminate randomly coinciding events in ZnMoO$_4$ cryogenic scintillating bolometers. These events can be effectively rejected at the level of 99% by the analysis of the heat signals with rise-time of about 14 ms and signal-to-noise ratio of 900, and at the level of 92% by the analysis of the light signals with rise-time of about 3 ms and signal-to-noise ratio of 30, under the requirement to detect 95% of single events. These rejection efficiencies are compatible with extremely low background levels in the region of interest of neutrinoless double beta decay of $^{100}$Mo for enriched ZnMoO$_4$ detectors, of the order of $10^{-4}$ counts/(y keV kg). Pulse-shape parameters ...

Chernyak, D M; Giuliani, A; Mancuso, M; Nones, C; Olivieri, E; Tenconi, M; Tretyak, V I

2014-01-01T23:59:59.000Z

463

U-Mo Foil/Cladding Interactions in Friction Stir Welded Monolithic RERTR Fuel Plates  

SciTech Connect (OSTI)

Interaction between U-Mo fuel and Al has proven to dramatically impact the overall irradiation performance of RERTR dispersion fuels. It is of interest to better understand how similar interactions may affect the performance of monolithic fuel plates, where a uranium alloy fuel is sandwiched between aluminum alloy cladding. The monolithic fuel plate removes the fuel matrix entirely, which reduces the total surface area of the fuel that is available to react with the aluminum and moves the interface between the fuel and cladding to a colder region of the fuel plate. One of the major fabrication techniques for producing monolithic fuel plates is friction stir welding. This paper will discuss the interactions that can occur between the U-Mo foil and 6061 Al cladding when applying this fabrication technique. It has been determined that the time at high temperatures should be limited as much as is possible during fabrication or any post-fabrication treatment to reduce as much as possible the interactions between the foil and cladding. Without careful control of the fabrication process, significant interaction between the U-Mo foil and Al alloy cladding can result. The reaction layers produced from such interactions can exhibit notably different morphologies vis-à-vis those typically observed for dispersion fuels.

D.D. Keiser; J.F. Jue; C.R. Clark

2006-10-01T23:59:59.000Z

464

Traces on ion yields and electron spectra of Ar inner-shell hollow states with Free-Electron Lasers  

E-Print Network [OSTI]

We explore the formation by Free-Electron-Laser radiation of Ar hollow states with two or three inner-shell holes. We find that even charged Ar ion states can be more populated than odd charged Ar ion states. This depends on the pulse intensity and the number of energetically accessible inner- shell holes. Fully accounting for fine structure, we demonstrate that one electron spectra bare the imprints of Ar hollow states with two inner-shell holes. Moreover, we show how the Auger spectra of these hollow states can be extracted from two-electron coincidence spectra.

Wallis, A O G; Emmanouilidou, A

2015-01-01T23:59:59.000Z

465

Superconducting and structural properties of {delta}-MoC{sub 0.681} cubic molybdenum carbide phase  

SciTech Connect (OSTI)

The superconducting and lattice properties of {delta}-MoC{sub 0.681} were studied by electromagnetic measurements, synchrotron X-ray diffraction, neutron diffraction, and electron diffraction. The superconducting properties (T{sub c}=12 K) of {delta}-MoC{sub 0.681} were well characterized by a weak coupling model. The carbon vacancies present in the host cubic structure were found to be robust, although the material was synthesized from stoichiometric carbon and Mo powder under a high-pressure of 6 GPa. A thermodynamically-stable structure with ordered vacancies did not account for the robust features of {delta}-MoC{sub 0.681} since the vacancies are unlikely to be ordered in long range in the host structure. A model based on inherent phonon instability theoretically predicted for a stoichiometric MoC phase might be responsible for the robust features of {delta}-MoC{sub 0.681}. - Graphical Abstract: The cubic molybdenum carbide shows an excellent superconductivity with robust carbon vacancies. Inherent phonon instability theoretically predicted for a stoichiometric MoC phase might be responsible for the vacancies rather than a thermodynamically-stable structure with vacancies ordering. Highlights: Black-Right-Pointing-Pointer The 12 K superconductivity is well characterized by a weakly coupling model. Black-Right-Pointing-Pointer Carbon vacancies are robust and disordered in the cubic host structure. Black-Right-Pointing-Pointer Inherent phonon instability might be responsible for the robust carbon vacancies in {delta}-MoC{sub 0.681}.

Sathish, C.I. [Graduate School of Chemical Sciences and Engineering, Hokkaido University, Sapporo, Hokkaido 060-0810 (Japan) [Graduate School of Chemical Sciences and Engineering, Hokkaido University, Sapporo, Hokkaido 060-0810 (Japan); Superconducting Properties Unit, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan); Guo, Yanfeng, E-mail: GUO.Yanfeng@nims.go.jp [Superconducting Properties Unit, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)] [Superconducting Properties Unit, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan); Wang, Xia [Graduate School of Chemical Sciences and Engineering, Hokkaido University, Sapporo, Hokkaido 060-0810 (Japan) [Graduate School of Chemical Sciences and Engineering, Hokkaido University, Sapporo, Hokkaido 060-0810 (Japan); Superconducting Properties Unit, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan); Tsujimoto, Yoshihiro [International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)] [International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan); Li, Jun [Graduate School of Chemical Sciences and Engineering, Hokkaido University, Sapporo, Hokkaido 060-0810 (Japan) [Graduate School of Chemical Sciences and Engineering, Hokkaido University, Sapporo, Hokkaido 060-0810 (Japan); Superconducting Properties Unit, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan); Zhang, Shoubao [International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)] [International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan); Matsushita, Yoshitaka [Synchrotron X-ray Station at SPring-8, National Institute for Materials Science, 1-1-1 Kouto, Sayo-cho, Hyogo 679-5148 (Japan)] [Synchrotron X-ray Station at SPring-8, National Institute for Materials Science, 1-1-1 Kouto, Sayo-cho, Hyogo 679-5148 (Japan); Shi, Youguo; Tian, Huanfang; Yang, Huaixin; Li, Jianqi [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China)] [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Yamaura, Kazunari, E-mail: YAMAURA.Kazunari@nims.go.jp [Graduate School of Chemical Sciences and Engineering, Hokkaido University, Sapporo, Hokkaido 060-0810 (Japan) [Graduate School of Chemical Sciences and Engineering, Hokkaido University, Sapporo, Hokkaido 060-0810 (Japan); Superconducting Properties Unit, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)

2012-12-15T23:59:59.000Z

466

Low-frequency 1/f noise in MoS{sub 2} transistors: Relative contributions of the channel and contacts  

SciTech Connect (OSTI)

We report on the results of the low-frequency (1/f, where f is frequency) noise measurements in MoS{sub 2} field-effect transistors revealing the relative contributions of the MoS{sub 2} channel and Ti/Au contacts to the overall noise level. The investigation of the 1/f noise was performed for both as fabricated and aged transistors. It was established that the McWhorter model of the carrier number fluctuations describes well the 1/f noise in MoS{sub 2} transistors, in contrast to what is observed in graphene devices. The trap densities extracted from the 1/f noise data for MoS{sub 2} transistors, are 2?×?10{sup 19}?eV{sup ?1}cm{sup ?3} and 2.5?×?10{sup 20}?eV{sup ?1}cm{sup ?3} for the as fabricated and aged devices, respectively. It was found that the increase in the noise level of the aged MoS{sub 2} transistors is due to the channel rather than the contact degradation. The obtained results are important for the proposed electronic applications of MoS{sub 2} and other van der Waals materials.

Renteria, J.; Jiang, C. [Nano-Device Laboratory, Department of Electrical Engineering, Bourns College of Engineering, University of California – Riverside, Riverside, California 92521 (United States); Samnakay, R. [Materials Science and Engineering Program, Bourns College of Engineering, University of California – Riverside, Riverside, California 92521 (United States); Rumyantsev, S. L. [Department of Electrical, Computer, and Systems Engineering, Center for Integrated Electronics, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States); Ioffe Physical-Technical Institute, St. Petersburg 194021 (Russian Federation); Goli, P.; Balandin, A. A., E-mail: balandin@ee.ucr.edu [Nano-Device Laboratory, Department of Electrical Engineering, Bourns College of Engineering, University of California – Riverside, Riverside, California 92521 (United States); Materials Science and Engineering Program, Bourns College of Engineering, University of California – Riverside, Riverside, California 92521 (United States); Shur, M. S. [Department of Electrical, Computer, and Systems Engineering, Center for Integrated Electronics, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States)

2014-04-14T23:59:59.000Z

467

A practical grinding-assisted dry synthesis of nanocrystalline NiMoO{sub 4} polymorphs for oxidative dehydrogenation of propane  

SciTech Connect (OSTI)

A practical two-stage reactive grinding-assisted pathway waste-free and cost-effective for the synthesis of NiMoO{sub 4} has been successfully developed. It was demonstrated that proper design in synthetic strategy for grinding plays a crucial role in determining the ultimate polymorph of NiMoO{sub 4}. Specifically, direct grinding (DG) of MoO{sub 3} and NiO rendered {alpha}-NiMoO{sub 4} after annealing, whereas sequential grinding (SG) of the two independently pre-ground oxides followed by annealing generated {beta}-NiMoO{sub 4} solid solution. Characterizations in terms of Raman and X-ray diffraction suggest the creation of {beta}-NiMoO{sub 4} precursor in the latter alternative is the key aspect for the formation of {beta}-NiMoO{sub 4}. The DG-derived {alpha}-NiMoO{sub 4} tested by oxidative dehydrogenation of propane exhibited superior activity in contrast to its analog synthesized via conventional coprecipitation. It is suggested that the favorable chemical composition facilely obtained via grinding in contrast to that by coprecipitation was essential for achieving a more selective production of propylene. - Graphical Abstract: Grinding-assisted synthesis of NiMoO{sub 4} offers higher and more reproducible activities in contrast to coprecipitation for oxidative dehydrogenation of propane, and both {alpha}- and {beta}-NiMoO{sub 4} can be synthesized. Highlights: Black-Right-Pointing-Pointer NiMoO{sub 4} was prepared through grinding-assisted pathway. Black-Right-Pointing-Pointer Direct/sequential grinding rendered {alpha}-, {beta}-NiMoO{sub 4}, respectively. Black-Right-Pointing-Pointer Grinding-derived {alpha}-NiMoO{sub 4} showed high and reproducible activity for oxidative dehydrogenation of propane.

Chen Miao, E-mail: chenmiao@sinochem.com [Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry, Fudan University, Shanghai 200433 (China); Zhejiang Chemical Industry Research Institute, Hangzhou 310023 (China); Wu Jialing; Liu Yongmei [Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry, Fudan University, Shanghai 200433 (China); Cao Yong, E-mail: yongcao@fudan.edu.cn [Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry, Fudan University, Shanghai 200433 (China); Guo Li [Zhejiang Chemical Industry Research Institute, Hangzhou 310023 (China); He Heyong; Fan Kangnian [Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry, Fudan University, Shanghai 200433 (China)

2011-12-15T23:59:59.000Z

468

Transmission electron microscopy of RSP Fe/Cr/Mn/Mo/C alloy. [Fe-3 wt % Cr-2 wt % Mn-0. 5 wt % Mo, -0. 3 wt % C  

SciTech Connect (OSTI)

Rapid solidification processing (RSP) has been carried out on an Fe/Cr/Mn/Mo/C alloy using both electron-beam melting and piston-and-anvil techniques. Preliminary TEM results show RSP produces a refined duplex microstructure of ferrite and martensite, with a typical ferrite grain size of 0.50 - 3.0 microns. This RSP microstructure is significantly different from that observed in the conventionally austenitized and quenched alloys - a lath martensitic microstructure with thin films of retained interlath austenite. The morphological change produced by RSP is accompanied by an increase in hardness from 48R/sub c/ to 61R/sub c/ (approx. 480 to 720 VHN). It is intended to use electron-beam specimens to examine the potential beneficial effect of RSP upon sliding wear resistance and, by careful TEM studies, it will be possible to characterize the microstructure and its role in the hardness and wear behavior of the RSP alloy.

Rayment, J.J.; Thomas, G.

1982-03-01T23:59:59.000Z

469

Identification of the feature that causes the I-band secondary maximum of a type Ia supernova  

E-Print Network [OSTI]

We obtained a time series of spectra covering the secondary maximum in the I-band of the bright Type Ia supernova 2014J in M82 with the TIGRE telescope. Comparing the observations with theoretical models calculated with the time dependent extension of the PHOENIX code, we identify the feature that causes the secondary maximum in the I-band light curve. Fe II 3d6(3D)4s-3d6(5D)4p and similar high excitation transitions produce a blended feature at 7500 {\\AA}, which causes the rise of the light curve towards the secondary maximum. The series of observed spectra of SN 2014J and archival data of SN 2011fe confirm this conclusion. We further studied the plateau phase