Sample records for milliseconds proton emission

  1. Systematics of proton emission

    E-Print Network [OSTI]

    D. S. Delion; R. J. Liotta; R. Wyss

    2006-01-24T23:59:59.000Z

    A very simple formula is presented that relates the logarithm of the half-life, corrected by the centrifugal barrier, with the Coulomb parameter in proton decay processes. The corresponding experimental data lie on two straight lines which appear as a result of a sudden change in the nuclear shape marking two regions of deformation independently of the angular momentum of the outgoing proton. This feature provides a powerful tool to assign experimentally quantum numbers in proton emitters.

  2. -delayed proton emission branches in 43Cr

    SciTech Connect (OSTI)

    Pomorski, M. [University of Warsaw; Miernik, K. [University of Warsaw; Dominik, W. [University of Warsaw; Janas, Z. [University of Warsaw; Pfutzner, M. [University of Warsaw; Bingham, C. R. [University of Tennessee, Knoxville (UTK); Czyrkowski, H. [University of Warsaw; Cwiok, Mikolaj [Warsaw University; Darby, Iain [University of Tennessee, Knoxville (UTK); Dabrowski, Ryszard [Warsaw University; Ginter, T. N. [Michigan State University, East Lansing; Grzywacz, Robert Kazimierz [ORNL; Karny, M. [University of Warsaw; Korgul, A. [University of Warsaw; Kusmierz, W. [University of Warsaw; Liddick, Sean [University of Tennessee, Knoxville (UTK); Rajabali, M. M. [University of Tennessee, Knoxville (UTK); Rykaczewski, Krzysztof Piotr [ORNL; Stolz, A. [Michigan State University, East Lansing

    2011-01-01T23:59:59.000Z

    The + decay of very neutron-deficient 43Cr was studied by means of an imaging time projection chamber that allowed recording tracks of charged particles. Events of -delayed emission of one, two, and three protons were clearly identified. The absolute branching ratios for these channels were determined to be (81 4)%, (7.1 0.4)%, and (0.08 0.03)%, respectively. 43Cr is thus established as the second case in which the -3p decay occurs. Although the feeding to the proton-bound states in 43V is expected to be negligible, the large branching ratio of (12 4)% for decays without proton emission is found.

  3. PROBING MILLISECOND PULSAR EMISSION GEOMETRY USING LIGHT CURVES FROM THE FERMI/LARGE AREA TELESCOPE

    SciTech Connect (OSTI)

    Venter, C.; Harding, A. K. [Astrophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Guillemot, L. [Universite de Bordeaux, Centre d'Etudes Nucleaires Bordeaux Gradignan, UMR 5797, Gradignan, 33175 (France)

    2009-12-10T23:59:59.000Z

    An interesting new high-energy pulsar sub-population is emerging following early discoveries of gamma-ray millisecond pulsars (MSPs) by the Fermi Large Area Telescope (LAT). We present results from three-dimensional emission modeling, including the special relativistic effects of aberration and time-of-flight delays and also rotational sweepback of B-field lines, in the geometric context of polar cap (PC), outer gap (OG), and two-pole caustic (TPC) pulsar models. In contrast to the general belief that these very old, rapidly rotating neutron stars (NSs) should have largely pair-starved magnetospheres due to the absence of significant pair production, we find that most of the light curves are best fit by TPC and OG models, which indicates the presence of narrow accelerating gaps limited by robust pair production-even in these pulsars with very low spin-down luminosities. The gamma-ray pulse shapes and relative phase lags with respect to the radio pulses point to high-altitude emission being dominant for all geometries. We also find exclusive differentiation of the current gamma-ray MSP population into two MSP sub-classes: light curve shapes and lags across wavebands impose either pair-starved PC (PSPC) or TPC/OG-type geometries. In the first case, the radio pulse has a small lag with respect to the single gamma-ray pulse, while the (first) gamma-ray peak usually trails the radio by a large phase offset in the latter case. Finally, we find that the flux correction factor as a function of magnetic inclination and observer angles is typically of order unity for all models. Our calculation of light curves and flux correction factor for the case of MSPs is therefore complementary to the 'ATLAS paper' of Watters et al. for younger pulsars.

  4. Proton emission induced by polarized photons

    E-Print Network [OSTI]

    M. Anguiano; G. Co'; A. M. Lallena

    2006-08-29T23:59:59.000Z

    The proton emission induced by polarized photons is studied in the energy range above the giant resonance region and below the pion emission threshold. Results for the 12C, 16O and 40Ca nuclei are presented. The sensitivity of various observables to final state interaction, meson exchange currents and short range correlations is analyzed. We found relevant effects due to the virtual excitation of the $\\Delta$ resonance.

  5. Gamma-ray emission states in the redback millisecond pulsar binary system PSR J1227-4853

    E-Print Network [OSTI]

    Bednarek, W

    2015-01-01T23:59:59.000Z

    Long expected transition states between the rotation powered and accretion powered non-thermal emission in the millisecond pulsar binary systems have been recently observed in the case of three objects PSR J1023+0038, PSR J1824-2452, and PSR J1227-4859. Surprisingly, the transition is related to the significant change in the $\\gamma$-ray flux being a factor of a few higher with the presence of an accretion disk. The origin of this enhanced emission seems to be related to the penetration of the inner pulsar magnetosphere by the accretion disk. We propose that the radiation processes, characteristic for the rotation powered pulsar, can co-exist with the presence of an accretion disk in the inner pulsar magnetosphere. In our scenario additional $\\gamma$-ray emission is produced by secondary leptons, originated close to the acceleration gap, which Compton up-scatter thermal radiation from the accretion disk to GeV energies. The accretion disk penetrates deep into the pulsar magnetosphere allowing the matter to fa...

  6. Reverse Shock Emission and Ionization Break Out Powered by Post-merger Millisecond Magnetars

    E-Print Network [OSTI]

    Wang, Ling-Jun; Yu, Yun-Wei

    2015-01-01T23:59:59.000Z

    There is accumulating evidence that at least a fraction of binary neutron star mergers result in rapidly spinning magnetars, with subrelativistic neutron-rich ejecta as massive as a small fraction of solar mass. The ejecta could be heated continuously by the Poynting flux emanated from the central magnetars. Such Poynting flux could become lepton-dominated so that a reverse shock develops. It was demonstrated that such a picture is capable of accounting for the optical transient PTF11agg (Wang & Dai 2013b). In this paper we investigate the X-ray and ultraviolet (UV) radiation as well as the optical and radio radiation studied by Wang & Dai (2013b). UV emission is particularly important because it has the right energy to ionize the hot ejecta at times $t\\lesssim 600$ s. It is thought that the ejecta of binary neutron star mergers are a remarkably pure sample of r-process material, about which our understanding is still incomplete. In this paper we evaluate the possibility of observationally determining...

  7. One proton, two proton, and alpha emission from 14o+alpha resonance interactions 

    E-Print Network [OSTI]

    Fu, Changbo

    2009-05-15T23:59:59.000Z

    In this dissertation, proton, two proton, and emission from the 14O + a interactions were studied with the modified thick target inverse kinematics approach. The radioactive beam was obtained by using resonances in the 14N(p, n)14O reaction. The 14...

  8. Light meson emission in (anti)proton induced reactions

    E-Print Network [OSTI]

    E. A. Kuraev; E. S. Kokoulina; E. Tomasi-Gustafsson

    2015-03-07T23:59:59.000Z

    Reactions induced by high energy antiprotons on proton on nuclei are accompanied with large probability by the emission of a few mesons. Interesting phenomena can be observed and QCD tests can be performed, through the detection of one or more mesons. The collinear emission from high energy (anti)proton beams of a hard pion or vector meson, can be calculated similarly to the emission of a hard photon from an electron \\cite{Kuraev:2013izz}. This is a well known process in QED, and it is called the "Quasi-Real Electron method", where the incident particle is an electron and a hard photon is emitted leaving an 'almost on shell' electron impinging on the target \\cite{Baier:1973ms}. Such process is well known as Initial State Emission (ISR) method of scanning over incident energy, and can be used, in the hadron case, to produce different kind of particles in similar kinematical conditions. In case of emission of a charged light meson, $\\pi$ or $\\rho$-meson, in proton-proton(anti-proton) collisions, the meson can be deviated in a magnetic field and detected. The collinear emission (along the beam direction) of a charged meson may be used to produce high energy (anti)neutron beams. This can be very useful to measure the difference of the cross sections of (anti)proton and (anti)neutron scattering from the target and may open the way for checking sum rules with antiparticles. Hard meson emission allows also to enhance the cross section when the energy loss from one of the incident particles lowers the total energy up to the mass of a resonance. The cross section can be calculated, on the basis of factorized formulas, where the probability of emission of the light mesons multiplies the cross section of the sub-process. Multiplicity distributions for neutral and charged meson production are also given.

  9. Light meson emission in (anti)proton induced reactions

    E-Print Network [OSTI]

    Kuraev, E A; Tomasi-Gustafsson, E

    2015-01-01T23:59:59.000Z

    Reactions induced by high energy antiprotons on proton on nuclei are accompanied with large probability by the emission of a few mesons. Interesting phenomena can be observed and QCD tests can be performed, through the detection of one or more mesons. The collinear emission from high energy (anti)proton beams of a hard pion or vector meson, can be calculated similarly to the emission of a hard photon from an electron \\cite{Kuraev:2013izz}. This is a well known process in QED, and it is called the "Quasi-Real Electron method", where the incident particle is an electron and a hard photon is emitted leaving an 'almost on shell' electron impinging on the target \\cite{Baier:1973ms}. Such process is well known as Initial State Emission (ISR) method of scanning over incident energy, and can be used, in the hadron case, to produce different kind of particles in similar kinematical conditions. In case of emission of a charged light meson, $\\pi$ or $\\rho$-meson, in proton-proton(anti-proton) collisions, the meson can b...

  10. He-proton emission imaging for inertial-confinement-fusion experiments (invited)

    E-Print Network [OSTI]

    D3 He-proton emission imaging for inertial-confinement-fusion experiments (invited) F. H. Séguin, Livermore, California 94550 (Presented on 19 April 2004; published 5 October 2004) Proton emission imaging cameras, in combination with proton spectrometers and a proton temporal diagnostic, provide a great deal

  11. Beta-delayed proton emission from $^{21}$Mg

    E-Print Network [OSTI]

    Lund, M V; Briz, J A; Cederkäll, J; Fynbo, H O U; Jensen, J H; Jonson, B; Laursen, K L; Nilsson, T; Perea, A; Pesudo, V; Riisager, K; Tengblad, O

    2015-01-01T23:59:59.000Z

    Beta-delayed proton emission from $^{21}$Mg has been measured at ISOLDE, CERN, with a detection setup including particle identification capabilities. $\\beta$-delayed protons with center of mass energies between 0.39$\\,$MeV and 7.2$\\,$MeV were measured and used to determine the half life of $^{21}$Mg as $118.6\\pm 0.5\\,$ms. From a line shape fit of the $\\beta p$ branches we extract spectroscopic information about the resonances of $^{21}$Na. Finally an improved interpretation of the decay scheme in accordance with the results obtained in reaction studies is presented.

  12. Proc. of Atmospheric Studies by Optical Methods (2001) :16 Optical Emissions from Proton Aurora

    E-Print Network [OSTI]

    Lummerzheim, Dirk

    2001-01-01T23:59:59.000Z

    Proc. of Atmospheric Studies by Optical Methods (2001) :1­6 Optical Emissions from Proton Aurora D of proton aurora. The Doppler-shifted hydrogen emission lines can be inter- preted in terms of the mean in electron aurora, the relative brightness of emis- sion features differs from that in electron aurora

  13. Different mechanism of two-proton emission from proton-rich nuclei $^{23}$Al and $^{22}$Mg

    E-Print Network [OSTI]

    Y. G. Ma; D. Q. Fang; X. Y. Sun; P. Zhou; Y. Togano; N. Aoi; H. Baba; X. Z. Cai; X. G. Cao; J. G. Chen; Y. Fu; W. Guo; Y. Hara; T. Honda; Z. G. Hu; K. Ieki; Y. Ishibashi; Y. Ito; N. Iwasa; S. Kanno; T. Kawabata; H. Kimura; Y. Kondo; K. Kurita; M. Kurokawa; T. Moriguchi; H. Murakami; H. Ooishi; K. Okada; S. Ota; A. Ozawa; H. Sakurai; S. Shimoura; R. Shioda; E. Takeshita; S. Takeuchi; W. D. Tian; H. W. Wang; J. S. Wang; M. Wang; K. Yamada; Y. Yamada; Y. Yasuda; K. Yoneda; G. Q. Zhang; T. Motobayashi

    2015-03-19T23:59:59.000Z

    Two-proton relative momentum ($q_{pp}$) and opening angle ($\\theta_{pp}$) distributions from the three-body decay of two excited proton-rich nuclei, namely $^{23}$Al $\\rightarrow$ p + p + $^{21}$Na and $^{22}$Mg $\\rightarrow$ p + p + $^{20}$Ne, have been measured with the projectile fragment separator (RIPS) at the RIKEN RI Beam Factory. An evident peak at $q_{pp}\\sim20$ MeV/c as well as a peak in $\\theta_{pp}$ around 30$^\\circ$ are seen in the two-proton break-up channel from a highly-excited $^{22}$Mg. In contrast, such peaks are absent for the $^{23}$Al case. It is concluded that the two-proton emission mechanism of excited $^{22}$Mg is quite different from the $^{23}$Al case, with the former having a favorable diproton emission component at a highly excited state and the latter dominated by the sequential decay process.

  14. Different mechanism of two-proton emission from proton-rich nuclei $^{23}$Al and $^{22}$Mg

    E-Print Network [OSTI]

    Ma, Y G; Sun, X Y; Zhou, P; Togano, Y; Aoi, N; Baba, H; Cai, X Z; Cao, X G; Chen, J G; Fu, Y; Guo, W; Hara, Y; Honda, T; Hu, Z G; Ieki, K; Ishibashi, Y; Ito, Y; Iwasa, N; Kanno, S; Kawabata, T; Kimura, H; Kondo, Y; Kurita, K; Kurokawa, M; Moriguchi, T; Murakami, H; Ooishi, H; Okada, K; Ota, S; Ozawa, A; Sakurai, H; Shimoura, S; Shioda, R; Takeshita, E; Takeuchi, S; Tian, W D; Wang, H W; Wang, J S; Wang, M; Yamada, K; Yamada, Y; Yasuda, Y; Yoneda, K; Zhang, G Q; Motobayashi, T

    2015-01-01T23:59:59.000Z

    Two-proton relative momentum ($q_{pp}$) and opening angle ($\\theta_{pp}$) distributions from the three-body decay of two excited proton-rich nuclei, namely $^{23}$Al $\\rightarrow$ p + p + $^{21}$Na and $^{22}$Mg $\\rightarrow$ p + p + $^{20}$Ne, have been measured with the projectile fragment separator (RIPS) at the RIKEN RI Beam Factory. An evident peak at $q_{pp}\\sim20$ MeV/c as well as a peak in $\\theta_{pp}$ around 30$^\\circ$ are seen in the two-proton break-up channel from a highly-excited $^{22}$Mg. In contrast, such peaks are absent for the $^{23}$Al case. It is concluded that the two-proton emission mechanism of excited $^{22}$Mg is quite different from the $^{23}$Al case, with the former having a favorable diproton emission component at a highly excited state and the latter dominated by the sequential decay process.

  15. Biomedical applications of proton induced X-ray emission

    SciTech Connect (OSTI)

    Vis, R.D.

    1988-06-01T23:59:59.000Z

    Apart from studies on aerosols, the majority of applications of proton induced X-ray emission (PIXE) with a normal beam or a microprobe (micro-PIXE) is found in biology and medicine. Two aspects of broad beam PIXE are often decisive for the choice of this analytical technique. Compared to other techniques capable of analysis down beyond the ppm level, PIXE can be carried out with a very small amount of material and minute fractions of the composite samples, even in the scale of micrometers and quite often with minimal sample preparation, which are important requirements for biomedical investigations. Secondly, the speed of the total analysis opens the possibility to analyze large numbers of samples in a reasonable time, which is often necessary in biomedical studies in order to obtain sufficiently significant correlations between trace element concentrations and biomedical phenomena. Few, if any, techniques can compete with micro-PIXE; quantitative trace element analysis on a micrometer scale still represent a challenging problem. The electron microprobe normally lacks the sensitivity while the laser induced techniques suffer as yet from quantification problems. This paper describes recent developments especially in micro-PIXE in biomedical research.

  16. Transport properties and neutrino emissivity of dense neutron-star matter with localized protons

    E-Print Network [OSTI]

    D. A. Baiko; P. Haensel

    1999-06-18T23:59:59.000Z

    As pointed out by Kutschera and W{\\'o}jcik, very low concentration of protons combined with a specific density dependence of effective neutron-proton interaction could lead to a localization of ``proton impurities'' in neutron medium at densities exceeding four times normal nuclear matter density. We study consequences of the localization of protons for transport processes in dense neutron star cores, assuming random distribution of proton impurities. Kinetic equations, relevant for the transport of charge, heat and momentum, are solved using variational method. Localization of protons removes a T^{-2} factor from the transport coefficients, which leads, at lower temperatures, to a strong decrease of thermal conductivity, electrical conductivity and shear viscosity of neutron star matter, as compared to the standard case, where protons form a Fermi liquid. Due to the localization of protons a number of conventional neutrino emission processes (including modified URCA process) become inoperative in neutron star cores. On the other hand, the energy loss rate from neutrino-antineutrino pair bremsstrahlung due to electron and neutron scattering off (localized) protons, will have a specific T^6 dependence, which could modify the cooling of the neutron star core, as compared to the standard case. Possible astrophysical implications of the localization of protons for neutron star evolution and dynamics are discussed.

  17. First Observation of Beta-Delayed Three-Proton Emission in 45Fe

    SciTech Connect (OSTI)

    Miernik, K. [University of Warsaw; Dominik, Wojciech [Warsaw University; Janas, Z. [University of Warsaw; Pfutzner, M. [University of Warsaw; Bingham, C. R. [University of Tennessee, Knoxville (UTK); Czyrkowski, Henryk [Warsaw University; Cwiok, Mikolaj [Warsaw University; Darby, Iain [University of Tennessee, Knoxville (UTK); Djbrowski, R. [University of Warsaw; Ginter, T. N. [Michigan State University, East Lansing; Grzywacz, R. [University of Tennessee, Knoxville (UTK); Karny, M. [University of Warsaw; Korgul, A. [University of Warsaw; Kusmierz, W. [University of Warsaw; Liddick, Sean [University of Tennessee, Knoxville (UTK); Rajabali, Mustafa [University of Tennessee, Knoxville (UTK); Rykaczewski, Krzysztof Piotr [ORNL; Stolz, A. [Michigan State University, East Lansing

    2007-01-01T23:59:59.000Z

    The decay of extremely neutron deficient 45Fe has been studied by means of a new type of a gaseous detector in which a technique of digital imaging was used to record tracks of charged particles. The + decay channels accompanied by proton emission were clearly identified. In addition to -delayed one-proton and -delayed two-proton decays, -delayed three-proton emission was recorded which represents the first direct and unambiguous observation of this decay channel. The branching ratio for the decay of 45Fe and the corresponding partial half-life are found to be 0.30 0.04 and T1/2( ) = 8.7 1.3 ms, respectively.

  18. First observation of {beta}-delayed three-proton emission in {sup 45}Fe

    SciTech Connect (OSTI)

    Miernik, K.; Dominik, W.; Janas, Z.; Pfuetzner, M.; Czyrkowski, H.; Cwiok, M.; DaPbrowski, R.; Karny, M.; Korgul, A.; Kusmierz, W. [Institute of Experimental Physics, Warsaw University, PL-00-681 Warsaw (Poland); Bingham, C. R.; Darby, I. G.; Liddick, S. N.; Rajabali, M. [Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996 (United States); Ginter, T.; Stolz, A. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States); Grzywacz, R. [Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996 (United States); Physics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Rykaczewski, K. [Physics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

    2007-10-15T23:59:59.000Z

    The decay of extremely neutron deficient {sup 45}Fe has been studied by means of a new type of a gaseous detector in which a technique of digital imaging was used to record tracks of charged particles. The {beta}{sup +} decay channels accompanied by proton emission were clearly identified. In addition to {beta}-delayed one-proton and {beta}-delayed two-proton decays, {beta}-delayed three-proton emission was recorded which represents the first direct and unambiguous observation of this decay channel. The branching ratio for the {beta} decay of {sup 45}Fe and the corresponding partial half-life are found to be 0.30{+-}0.04 and T{sub 1/2}({beta})=8.7{+-}1.3 ms, respectively.

  19. One proton, two proton, and alpha emission from 14o+alpha resonance interactions

    E-Print Network [OSTI]

    Fu, Changbo

    2009-05-15T23:59:59.000Z

    ) reactions occurring at different places in the helium gas target were identified. With this information, we were able to measure a spectrum of protons corresponding to the population of 17F particle stable states in the 14O(a, p)17F reaction. This method...

  20. Millisecond Oxidation of Alkanes

    SciTech Connect (OSTI)

    Scott Han

    2011-09-30T23:59:59.000Z

    This project was undertaken in response to the Department of Energy's call to research and develop technologies 'that will reduce energy consumption, enhance economic competitiveness, and reduce environmental impacts of the domestic chemical industry.' The current technology at the time for producing 140 billion pounds per year of propylene from naphtha and Liquified Petroleum Gas (LPG) relied on energy- and capital-intensive steam crackers and Fluidized Catalytic Cracking (FCC) units. The propylene is isolated from the product stream in a costly separation step and subsequently converted to acrylic acid and other derivatives in separate production facilities. This project proposed a Short Contact Time Reactor (SCTR)-based catalytic oxydehydrogenation process that could convert propane to propylene and acrylic acid in a cost-effective and energy-efficient fashion. Full implementation of this technology could lead to sizeable energy, economic and environmental benefits for the U. S. chemical industry by providing up to 45 trillion BTUs/year, cost savings of $1.8 billion/year and a combined 35 million pounds/year reduction in environmental pollutants such as COx, NOx, and SOx. Midway through the project term, the program directive changed, which approval from the DOE and its review panel, from direct propane oxidation to acrylic acid at millisecond contact times to a two-step process for making acrylic acid from propane. The first step was the primary focus, namely the conversion of propane to propylene in high yields assisted by the presence of CO2. The product stream from step one was then to be fed directly into a commercially practiced propylene-to-acrylic acid tandem reactor system.

  1. The Effects of {beta}-Delayed Proton Emission on the Path of the rp-Process

    SciTech Connect (OSTI)

    Boyd, R.N.

    2000-12-31T23:59:59.000Z

    The rp-process occurs in a hot hydrogen-rich stellar environment. Its trajectory passes through the most proton-rich nuclides in the periodic table. It has long been thought to be responsible for synthesizing at least the light p-process nuclides. Thus these nuclides can provide signatures for rp-process nucleosynthesis. Difficulties with various rp-process scenarios often focus on {sup 92,94}Mo and {sup 96,98}Ru p-nuclides, as their anomalously large abundances are difficult to produce in any model of nucleosynthesis. However, it now appears that they might be produced in the rp-process resulting from accretion onto a neutron star. If the rp-process does synthesize these nuclides, {beta}-delayed proton emission might well resolve some of the difficulties made evident by the model calculations.

  2. Proton-

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible forPortsmouth/Paducah47,193.70 HgPromisingProtectingSciTechProton DrippingWeakProton- 3

  3. Millisecond Oxidation of Alkanes

    Broader source: Energy.gov [DOE]

    This factsheet describes a project whose goal is to commercialize a production process for propylene and acrylic acid from propane using a catalytic auto-thermal oxydehydrogenation process operating at short contact times. Auto-thermal oxidation for conversion of propane to propylene and acrylic acid promises energy savings of 20 trillion Btu per year by 2020. In addition to reducing energy consumption, this technology can reduce manufacturing costs by up to 25 percent, and reduce a variety of greenhouse gas emissions.

  4. Investigating fusion plasma instabilities in the Mega Amp Spherical Tokamak using mega electron volt proton emissions (invited)

    SciTech Connect (OSTI)

    Perez, R. V., E-mail: rvale006@fiu.edu; Boeglin, W. U.; Angulo, A.; Avila, P.; Leon, O.; Lopez, C. [Department of Physics, Florida International University, 11200 SW 8 ST, CP204, Miami, Florida 33199 (United States); Darrow, D. S. [Princeton Plasma Physics Laboratory, James Forrestal Campus, P.O. Box 451, Princeton, New Jersey 08543 (United States); Cecconello, M.; Klimek, I. [Department of Physics and Astronomy, Uppsala University, Uppsala SE-751 20 (Sweden); Allan, S. Y.; Akers, R. J.; Keeling, D. L.; McClements, K. G.; Scannell, R.; Conway, N. J. [CCFE, Culham Science Centre, Abingdon, Oxfordshire OX14 3DB (United Kingdom); Turnyanskiy, M. [ITER Physics Department, EFDA CSU Garching, Boltzmannstrasse 2, D-85748, Garching (Germany); Jones, O. M. [CCFE, Culham Science Centre, Abingdon, Oxfordshire OX14 3DB (United Kingdom); Department of Physics, Durham University, Durham DH1 3LE (United Kingdom); Michael, C. A. [Australian National University, Canberra ACT 0200 (Australia)

    2014-11-15T23:59:59.000Z

    The proton detector (PD) measures 3 MeV proton yield distributions from deuterium-deuterium fusion reactions within the Mega Amp Spherical Tokamak (MAST). The PD’s compact four-channel system of collimated and individually oriented silicon detectors probes different regions of the plasma, detecting protons (with gyro radii large enough to be unconfined) leaving the plasma on curved trajectories during neutral beam injection. From first PD data obtained during plasma operation in 2013, proton production rates (up to several hundred kHz and 1 ms time resolution) during sawtooth events were compared to the corresponding MAST neutron camera data. Fitted proton emission profiles in the poloidal plane demonstrate the capabilities of this new system.

  5. Green Bank Telescope Studies of Giant Pulses from Millisecond Pulsars

    E-Print Network [OSTI]

    H. S. Knight; M. Bailes; R. N. Manchester; S. M. Ord; B. A. Jacoby

    2005-12-13T23:59:59.000Z

    We have conducted a search for giant pulses from four millisecond pulsars using the 100m Green Bank Telescope. Coherently dedispersed time-series from PSR J0218+4232 were found to contain giant pulses of very short intrinsic duration whose energies follow power-law statistics. The giant pulses are in phase with the two minima of the radio integrated pulse profile but are phase aligned with the peaks of the X-ray profile. Historically, individual pulses more than 10-20 times the mean pulse energy have been deemed to be ``giant pulses''. As only 4 of the 155 pulses had energies greater than 10 times the mean pulse-energy, we argue the emission mechanism responsible for giant pulses should instead be defined through: (a) intrinsic timescales of microsecond or nanosecond duration; (b) power-law energy statistics; and (c) emission occurring in narrow phase-windows coincident with the phase windows of non-thermal X-ray emission. Four short-duration pulses with giant-pulse characteristics were also observed from PSR B1957+20. As the inferred magnetic fields at the light cylinders of the millisecond pulsars that emit giant pulses are all very high, this parameter has previously been considered to be an indicator of giant pulse emissivity. However, the frequency of giant pulse emission from PSR~B1957+20 is significantly lower than for other millisecond pulsars that have similar magnetic fields at their light cylinders. This suggests that the inferred magnetic field at the light cylinder is a poor indicator of the rate of emission of giant pulses.

  6. Optical emission spectroscopy of the Linac4 and superconducting proton Linac plasma generators

    SciTech Connect (OSTI)

    Lettry, J.; Kronberger, M.; Mahner, E.; Schmitzer, C.; Sanchez, J.; Scrivens, R.; Midttun, O.; O'Neil, M.; Pereira, H.; Paoluzzi, M. [European Organization for Nuclear Research, CERN, 1211 Geneva 23 (Switzerland); Fantz, U.; Wuenderlich, D. [Max-Planck-Institut fuer Plasmaphysik, IPP, 85748 Garching (Germany); Kalvas, T.; Koivisto, H.; Komppula, J.; Myllyperkioe, P.; Tarvainen, O. [Department of Physics, University of Jyvaeskylae, 40500 Jyvaeskylae (Finland)

    2012-02-15T23:59:59.000Z

    CERN's superconducting proton Linac (SPL) study investigates a 50 Hz high-energy, high-power Linac for H{sup -} ions. The SPL plasma generator is an evolution of the DESY ion source plasma generator currently operated at CERN's Linac4 test stand. The plasma generator is a step towards a particle source for the SPL, it is designed to handle 100 kW peak RF-power at a 6% duty factor. While the acquisition of an integrated hydrogen plasma optical spectrum is straightforward, the measurement of a time-resolved spectrum requires dedicated amplification schemes. The experimental setup for visible light based on photomultipliers and narrow bandwidth filters and the UV spectrometer setup are described. The H{sub {alpha}}, H{sub {beta}}, and H{sub {gamma}} Balmer line intensities, the Lyman band and alpha transition were measured. A parametric study of the optical emission from the Linac4 ion source and the SPL plasma generator as a function of RF-power and gas pressure is presented. The potential of optical emission spectrometry coupled to RF-power coupling measurements for on-line monitoring of short RF heated hydrogen plasma pulses is discussed.

  7. Cosmic-ray positrons from millisecond pulsars

    E-Print Network [OSTI]

    Venter, C; Harding, A K; Gonthier, P L; Büsching, I

    2015-01-01T23:59:59.000Z

    Observations by the Fermi Large Area Telescope of gamma-ray millisecond pulsar light curves imply copious pair production in their magnetospheres, and not exclusively in those of younger pulsars. Such pair cascades may be a primary source of Galactic electrons and positrons, contributing to the observed enhancement in positron flux above ~10 GeV. Fermi has also uncovered many new millisecond pulsars, impacting Galactic stellar population models. We investigate the contribution of Galactic millisecond pulsars to the flux of terrestrial cosmic-ray electrons and positrons. Our population synthesis code predicts the source properties of present-day millisecond pulsars. We simulate their pair spectra invoking an offset-dipole magnetic field. We also consider positrons and electrons that have been further accelerated to energies of several TeV by strong intrabinary shocks in black widow and redback systems. Since millisecond pulsars are not surrounded by pulsar wind nebulae or supernova shells, we assume that the p...

  8. Impurities in extruded cables: A proton-induced x-ray emission diagnostic study

    SciTech Connect (OSTI)

    Crine, J.P.; Hinrichsen, P.F.; Houdayer, A. (Institut de Recherche d'Hydro-Quebec, Varennes, PQ (Canada))

    1990-06-01T23:59:59.000Z

    The impurity contents and distributions in electrical trees grown in various field-aged XLPE distribution cables were measured by micro-Proton Induced X-ray Emission (PIXE). The objectives pursued in this preliminary study were the following. Determination of any possible correlation between electrical tree initiation and the nature of some specific impurities. Evaluation of micro-PIXE as a reliable analytical technique to measure impurities in localized defects, such as small trees. For that purpose we used the micro-PIXE facility of the Laboratoire de Physique Nucleaire at University of Montreal where proton beams of {approx}20 microns can be focused on small samples. From the emitted x-rays, it is possible to determine the nature and content of most impurities (whose content is above {approx}1 ppM). Cable samples with electrical trees grown either from insulation shield or from water trees were analyzed. A few field-aged cable samples containing breakdown channels of various sizes were also analyzed. The aim here was to determine whether impurities could still be detected after breakdown. The observations made can be summarized as follows: the electrical trees studied were heavily contaminated by a wide variety of impurities; electrical trees contain the same impurities as the connecting water trees and the amounts are about the same in both types of trees; provided that the energy released during breakdown is not too high, that is as long as breakdown channels remain small; the minimum level of contamination leading to tree growth is difficult to ascertain; no clear correlation can be established between the nature of impurities and electrical tree initiation; it cannot be determined whether contamination leads to tree initiation or whether contamination follows tree growth; and micro-PIXE is well suited to study impurities in electrical (and water) trees. 20 refs., 18 figs., 8 tabs.

  9. Assessment of the use of prompt gamma emission for proton therapy range verification

    E-Print Network [OSTI]

    Styczynski, John R

    2009-01-01T23:59:59.000Z

    PURPOSE: Prompt gamma rays emitted from proton-nucleus interactions in tissue present a promising non-invasive, in situ means of monitoring proton beam based radiotherapy. This study investigates the fluence and energy ...

  10. Measurements of nuclear $?$-ray line emission in interactions of protons and $?$ particles with N, O, Ne and Si

    E-Print Network [OSTI]

    H. Benhabiles-Mezhoud; J. Kiener; J. -P. Thibaud; V. Tatischeff; I. Deloncle; A. Coc; J. Duprat; C. Hamadache; A. Lefebvre-Schuhl; J. -C. Dalouzy; F. De Grancey; F. De Oliveira; F. Dayras; N. De Séréville; M. -G. Pellegriti; L. Lamia; S. Ouichaoui

    2010-11-11T23:59:59.000Z

    $\\gamma$-ray production cross sections have been measured in proton irradiations of N, Ne and Si and $\\alpha$-particle irradiations of N and Ne. In the same experiment we extracted also line shapes for strong $\\gamma$-ray lines of $^{16}$O produced in proton and $\\alpha$-particle irradiations of O. For the measurements gas targets were used for N, O and Ne and a thick foil was used for Si. All targets were of natural isotopic composition. Beams in the energy range up to 26 MeV for protons and 39 MeV for $\\alpha$-particles have been delivered by the IPN-Orsay tandem accelerator. The $\\gamma$ rays have been detected with four HP-Ge detectors in the angular range 30$^{\\circ}$ to 135$^{\\circ}$. We extracted 36 cross section excitation functions for proton reactions and 14 for $\\alpha$-particle reactions. For the majority of the excitation functions no other data exist to our knowledge. Where comparison with existing data was possible usually a very good agreement was found. It is shown that these data are very interesting for constraining nuclear reaction models. In particular the agreement of cross section calculations in the nuclear reaction code TALYS with the measured data could be improved by adjusting the coupling schemes of collective levels in the target nuclei $^{14}$N, $^{20,22}$Ne and $^{28}$Si. The importance of these results for the modeling of nuclear $\\gamma$-ray line emission in astrophysical sites is discussed.

  11. Origins of PM10 determined by the micro-proton induced X-ray emission spectra of single aerosol particles

    SciTech Connect (OSTI)

    Yue, W.S.; Li, X.L.; Wan, T.M.; Liu, J.F.; Zhang, G.L.; Li, Y. [Chinese Academy of Science, Shanghai (China). Shanghai Institute of Applied Physics

    2006-06-15T23:59:59.000Z

    The micro-proton induced X-ray emission (micro-PIXE) spectrum of a single aerosol particle (SAP) was considered as its fingerprint for tracing its origin. A proton microprobe was used to extract fingerprints of SAPs. Environmental monitoring samples of PM10 were collected from a heavy industrial area of Shanghai and were analyzed by proton microprobe for finding their pollution sources. In order to find the sources of SAPs collected from environmental monitoring sites, a fingerprint database of SAPS collected from various pollution Sources was established. The origins of samples collected through environmental monitoring were identified by comparison of the micro-PIXE spectra of SAPs with those of SAPs in the fingerprint database using a pattern recognition technique. The results of this study show that most of the measured PM10 is derived from metallurgic industry, soil dust, coal combustion, automobile exhaust, and motorcycle exhaust. The study also shows that the proton microprobe is an ideal tool for the analysis of SAPs. The unidentified particles of PM10 are classified into seven classes by hierarchical cluster analysis based on the element peak intensity in the spectra.

  12. DETECTION AND FLUX DENSITY MEASUREMENTS OF THE MILLISECOND PULSAR J2145–0750 BELOW 100 MHz

    SciTech Connect (OSTI)

    Dowell, J.; Taylor, G. B.; Craig, J.; Henning, P. A.; Schinzel, F. [Department of Physics and Astronomy, University of New Mexico, Albuquerque, NM 87131 (United States)] [Department of Physics and Astronomy, University of New Mexico, Albuquerque, NM 87131 (United States); Ray, P. S. [Space Science Division, Naval Research Laboratory, Washington, DC 20375 (United States)] [Space Science Division, Naval Research Laboratory, Washington, DC 20375 (United States); Blythe, J. N. [School of Physics, Georgia Institute of Technology, Atlanta, GA 3033 (United States)] [School of Physics, Georgia Institute of Technology, Atlanta, GA 3033 (United States); Clarke, T.; Helmboldt, J. F. [U.S. Naval Research Laboratory, Washington, DC 20375 (United States)] [U.S. Naval Research Laboratory, Washington, DC 20375 (United States); Ellingson, S. W.; Wolfe, C. N. [Bradley Department of Electrical and Computer Engineering, Virginia Tech, Blacksburg, VA 24061 (United States)] [Bradley Department of Electrical and Computer Engineering, Virginia Tech, Blacksburg, VA 24061 (United States); Lazio, T. J. W. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States)] [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Stovall, K., E-mail: jdowell@unm.edu [Center for Gravitational Wave Astronomy and Department of Physics and Astronomy, University of Texas at Brownsville, Brownsville, TX 78520 (United States)

    2013-09-20T23:59:59.000Z

    We present flux density measurements and pulse profiles for the millisecond pulsar PSR J2145–0750 spanning 37 to 81 MHz using data obtained from the first station of the Long Wavelength Array. These measurements represent the lowest frequency detection of pulsed emission from a millisecond pulsar to date. We find that the pulse profile is similar to that observed at 102 MHz. We also find that the flux density spectrum between ?40 MHz to 5 GHz is suggestive of a break and may be better fit by a model that includes spectral curvature with a rollover around 730 MHz rather than a single power law.

  13. Energy deposition spectra of simultaneous electron emissions from low energy protons

    E-Print Network [OSTI]

    DePriest, Kendall Russell

    1998-01-01T23:59:59.000Z

    track is more complicated than the normal LET/RBE relationship. Recent measurements of atomic cross-section indicate that interactions of low energy protons with target atoms sometimes produce two or more electrons simultaneously. However, these cross...

  14. BETA-DELAYED PROTON EMISSION IN NEUTRON-DEFICIENT LRNTHANIDE ISOTOPES

    E-Print Network [OSTI]

    Witmarth, P.A.

    2010-01-01T23:59:59.000Z

    J.C. Hardy and E. Hubert. "Beta-delayed Proton astd Alphahalf-lives from (a) the grou theory of beta decay and (b)from Nilsson/RPA beta-strength function calculations for the

  15. Proton emission imaging of the nuclear burn in inertial confinement fusion experiments

    E-Print Network [OSTI]

    DeCiantis, Joseph Loreto

    2005-01-01T23:59:59.000Z

    A proton core imaging system has been developed and extensively used for measuring the nuclear burn regions of inertial confinement fusion implosions. These imaging cameras, mounted to the 60-beam OMEGA laser facility, use ...

  16. Beta delayed emission of a proton by a one-neutron halo nucleus

    E-Print Network [OSTI]

    D. Baye; E. M. Tursunov

    2010-12-28T23:59:59.000Z

    Some one-neutron halo nuclei can emit a proton in a beta decay of the halo neutron. The branching ratio towards this rare decay mode is calculated within a two-body potential model of the initial core+neutron bound state and final core+proton scattering states. The decay probability per second is evaluated for the $^{11}$Be, $^{19}$C and $^{31}$Ne one-neutron halo nuclei. It is very sensitive to the neutron separation energy.

  17. Beta delayed emission of a proton by a one-neutron halo nucleus

    E-Print Network [OSTI]

    Baye, D

    2010-01-01T23:59:59.000Z

    Some one-neutron halo nuclei can emit a proton in a beta decay of the halo neutron. The branching ratio towards this rare decay mode is calculated within a two-body potential model of the initial core+neutron bound state and final core+proton scattering states. The decay probability per second is evaluated for the $^{11}$Be, $^{19}$C and $^{31}$Ne one-neutron halo nuclei. It is very sensitive to the neutron separation energy.

  18. SU-E-J-121: Measuring Prompt Gamma Emission Profiles with a Multi-Stage Compton Camera During Proton Beam Irradiation: Initial Studies

    SciTech Connect (OSTI)

    Polf, J; McCleskey, M [University of Maryland School of Medicine, Baltimore, MD (United States); Brown, S; Mann, J; He, Z [University of Michigan, Ann Arbor, MI (United States); Mackin, D; Beddar, S [MD Anderson Cancer Center, Houston, TX (United States); Zheng, Y [Procure Proton Therapy Center, Oklahoma City, OK (United States)

    2014-06-01T23:59:59.000Z

    Purpose: Recent studies have suggested that the characteristics of prompt gammas (PG) emitted during proton beam irradiation are advantageous for determining beam range during treatment delivery. The purpose of this work was to determine the feasibility of determining the proton beam range from PG data measured with a prototype Compton camera (CC) during proton beam irradiation. Methods: Using a prototype multi-stage CC the PG emission from a water phantom was measured during irradiation with clinical proton therapy beams. The measured PG emission data was used to reconstruct an image of the PG emission using a backprojection reconstruction algorithm. One dimensional (1D) profiles extracted from the PG images were compared to: 1) PG emission data measured at fixed depths using collimated high purity Germanium and Lanthanum Bromide detectors, and 2) the measured depth dose profiles of the proton beams. Results: Comparisons showed that the PG emission profiles reconstructed from CC measurements agreed very well with the measurements of PG emission as a function of depth made with the collimated detectors. The distal falloff of the measured PG profile was between 1 mm to 4 mm proximal to the distal edge of the Bragg peak for proton beam ranges from 4 cm to 16 cm in water. Doses of at least 5 Gy were needed for the CC to measure sufficient data to image the PG profile and localize the distal PG falloff. Conclusion: Initial tests of a prototype CC for imaging PG emission during proton beam irradiation indicated that measurement and reconstruction of the PG profile was possible. However, due to limitations of the operational parameters (energy range and count rate) of the current CC prototype, doses of greater than a typical treatment dose (?2 Gy) were needed to measure adequate PG signal to reconstruct viable images. Funding support for this project provided by a grant from DoD.

  19. Pion absorption on {sup 3}He and {sup 4}He with emission of three energetic protons

    SciTech Connect (OSTI)

    LADS Collaboration

    1997-06-01T23:59:59.000Z

    Results from a 4{pi} solid angle measurement of the reactions {sup 3}He({pi}{sup +},ppp) and {sup 4}He({pi}{sup +},ppp)n at incident pion energies of T{sub {pi}{sup +}}=70, 118, 162, 239, and 330 MeV are presented. For {sup 3}He the total absorption cross sections and their decomposition into two-proton and three-proton components are evaluated; for {sup 4}He the three-proton absorption cross sections are given. The differential distributions of the three-proton multinucleon absorption mode of both nuclei are analyzed and compared to each other by making use of a complete set of variables. The data are investigated for signatures of initial and final state interactions: it is found that more than half of the three-proton yield cannot be accounted for by cascade mechanisms. The remaining strength shows dependence on the incident pion angular momentum, but also structures that are not explained by simple semiclassical models. {copyright} {ital 1997} {ital The American Physical Society}

  20. SU-E-J-247: A Simulation of X-Ray Emission with Gold Nanoparticle Irradiated by Energetic Proton Beam

    SciTech Connect (OSTI)

    Newpower, M; Ahmad, S; Chen, Y [University of Oklahoma Health Sciences Center, Oklahoma City, OK (United States)

    2014-06-01T23:59:59.000Z

    Purpose: To investigate the proton induced X-ray emissions in gold-water mixture materials. Methods: In this study a Monte Carlo simulation was created using the GEANT4 toolkit (version 4.9.6). The geometry in this setup includes a 2 cm × 2 cm × 2 cm target, a scoring sphere (radius = 10 cm) and a 65 MeV planar proton source (2 cm × 2 cm). Four concentrations of a gold-water solution were irradiated with 5×10{sup 5} incident protons at a distance of 0.5 cm perpendicular to the surface of the target. The solutions of gold-water mixture had 10%, 5%, 1% and 0.5% of gold by mass, respectively. The number of photon emitting for the target was counted in the scoring sphere for the energy range of 0-86.0 keV in 0.1 keV bins. For this study the reference physics list PhysListEmStandard was used together with the x-ray fluorescence, Auger electron and PIXE (particle induced xray emission) options enabled. The range cuts for photons and electrons were set at 0.5 mm and 1.0 mm, respectively. Results: In the energy spectra of emitting X-ray fluorescence, peaks from gold K shell characteristic x-rays (68.8 and 66.9 keV) were observed. The number of counts under the peaks of Ka1 and Ka2 was found to increase with the increasing of the gold concentrations in the mixture materials. The X-ray yields (for both Ka1 and Ka2) when fitted with least-square method as a function of gold concentration demonstrate a linear dependency with R{sup 2} > 0.96. The Ka1yield per incident proton was found to be 0.0016 for 10% gold-water mixture solutions. Conclusion: This preliminary study with PIXE technique with gold nanoparticle has demonstrated potentials for its utilization in the development of range and dose verification methodology that is currently of great interest in the field of proton radiation therapy.

  1. New Proton Radioactivity Measurements

    E-Print Network [OSTI]

    Edinburgh, University of

    New Proton Radioactivity Measurements Richard J. Irvine Thesis submitted for the degree of Doctor to search for examples of proton emission from ground and low­lying states in odd­Z nuclei at the proton into a double­sided silicon strip detector system, where their subsequent particle decays (proton or alpha) were

  2. Modeling pulse profiles of accreting millisecond pulsars

    E-Print Network [OSTI]

    Juri Poutanen

    2008-09-14T23:59:59.000Z

    I review the basic observational properties of accreting millisecond pulsars that are important for understanding the physics involved in formation of their pulse profiles. I then discuss main effects responsible for shaping these profiles. Some analytical results that help to understand the results of simulations are presented. Constraints on the pulsar geometry and the neutron star equation of state obtained from the analysis of the pulse profiles are discussed.

  3. Semiclassical Distorted Wave Model Analysis of Backward Proton Emission from $(p,p^{\\prime}x)$ Reactions at Intermediate Energies

    E-Print Network [OSTI]

    M. K. Gaidarov; Y. Watanabe; K. Ogata; M. Kohno; M. Kawai; A. N. Antonov

    2003-07-28T23:59:59.000Z

    A semiclassical distorted wave (SCDW) model with Wigner transform of one-body density matrix is presented for multistep direct $(p,p^{\\prime}x)$ reactions to the continuum. The model uses Wigner distribution functions obtained in methods which include nucleon-nucleon correlations to a different extent, as well as Woods-Saxon (WS) single-particle wave function. The higher momentum components of target nucleons that play a crucial role in reproducing the high-energy part of the backward proton spectra are properly taken into account. This SCDW model is applied to analyses of multistep direct processes in $^{12}$C$(p,p^{\\prime}x)$, $^{40}$Ca$(p,p^{\\prime}x)$ and $^{90}$Zr$(p,p^{\\prime}x)$ in the incident energy range of 150--392 MeV. The double differential cross sections are calculated up to three-step processes. The calculated angular distributions are in good agreement with the experimental data, in particular at backward angles where the previous SCDW calculations with the WS single-particle wave function showed large underestimation. It is found that the result with the Wigner distribution function based on the coherent density fluctuation model provides overall better agreement with the experimental data over the whole emission energies.

  4. A propeller model for the sub-luminous disk state of the transitional millisecond pulsar PSR J1023+0038

    E-Print Network [OSTI]

    Papitto, A

    2015-01-01T23:59:59.000Z

    The discovery of millisecond pulsars switching between states powered either by the rotation of their magnetic field or by the accretion of matter, has recently proved the tight link shared by millisecond radio pulsars and neutron stars in low-mass X-ray binaries. Transitional millisecond pulsars also show an enigmatic intermediate state in which the neutron star is surrounded by an accretion disk, it emits coherent X-ray pulsations, but is sub-luminous in X-rays with respect to accreting neutron stars, and is brighter in gamma-rays than millisecond pulsars in the rotation-powered state. Here, we model the X-ray and gamma-ray emission observed from PSR J1023+0038 in such a state based on the assumption that most of the disk in-flow is propelled away by the rapidly rotating neutron star magnetosphere, and that electrons can be accelerated to energies of a few GeV at the turbulent disk-magnetosphere boundary. We show that the synchrotron and self-synchrotron Compton emission coming from such a region, together ...

  5. Light curves and polarization of accretion- and nuclear-powered millisecond pulsars

    E-Print Network [OSTI]

    Kerttu Viironen; Juri Poutanen

    2004-08-13T23:59:59.000Z

    We study theoretical X-ray light curves and polarization properties of accretion-powered millisecond pulsars. We assume that the radiation is produced in two antipodal spots at the neutron star surface which are associated with the magnetic poles. We compute the angle-dependent intensity and polarization produced in an electron-scattering dominated plane-parallel accretion shock in the frame of the shock. The observed flux, polarization degree and polarization angle are calculated accounting for special and general relativistic effects. The calculations also extended to the case of nuclear-powered millisecond pulsars -- X-ray bursts. In this case, we consider one spot and the radiation is assumed to be produced in the atmosphere of the infinite Thomson optical depth. The light curves and polarization profiles show a large diversity depending on the model parameters. Presented results can be used as a first step to understand the observed pulse profiles of accretion- and nuclear-powered millisecond pulsars. Future observations of the X-ray polarization will provide a valuable tool to test the geometry of the emission region and its physical characteristics.

  6. The Millisecond Magnetar Central Engine in short GRBs

    E-Print Network [OSTI]

    Lü, Hou-Jun; Lei, Wei-Hua; Li, Ye; Lasky, Paul D

    2015-01-01T23:59:59.000Z

    One favored progenitor model for short duration gamma-ray bursts (SGRBs) is the coalescence of two neutron stars (NS-NS). One possible outcome of such a merger would be a rapidly spinning, strongly magnetized neutron star (known as a millisecond magnetar). These magnetars may be "supra-massive", implying they would collapse to black holes after losing centrifugal support due to magnetic dipole spindown. By systematically analyzing the BAT-XRT light curves of all short GRBs detected by {\\em swift}, we test how well the data are consistent with this central engine model of short GRBs. We find that the so-called "extended emission" observed with BAT in some short GRBs are fundamentally the same component as the "internal X-ray plateau" as observed in many short GRBs, which is defined as a plateau in the lightcurve followed by a very rapid drop. Based on how likely a short GRB hosts a magnetar, we characterize the entire {\\em Swift} short GRB sample into three categories: the "internal plateau" sample, the "exter...

  7. Unique decay process: {beta}-delayed emission of a proton and a neutron by the {sup 11}Li halo nucleus

    SciTech Connect (OSTI)

    Baye, D.; Descouvemont, P.; Tursunov, E. M. [Physique Quantique, CP 165/82, and Physique Nucleaire Theorique et Physique Mathematique, CP 229, Universite Libre de Bruxelles (ULB), B-1050 Brussels (Belgium); Institute of Nuclear Physics, Uzbekistan Academy of Sciences, 100214, Ulugbek, Tashkent (Uzbekistan)

    2010-11-15T23:59:59.000Z

    The neutron-rich {sup 11}Li halo nucleus is unique among nuclei with known separation energies in its ability to emit a proton and a neutron in a {beta}-decay process. The branching ratio toward this rare decay mode is evaluated within a three-body model for the initial bound state and with Coulomb three-body final scattering states. The branching ratio should be comprised between two extreme cases, i.e., a lower bound 6x10{sup -12} obtained with a pure Coulomb wave and an upper bound 5x10{sup -10} obtained with a plane wave. A simple model with modified Coulomb waves provides plausible values between 0.8x10{sup -10} and 2.2x10{sup -10}, with most probable total energies of the proton and neutron between 0.15 and 0.3 MeV.

  8. A unique decay process: beta delayed emission of a proton and a neutron by the $^{11}$Li halo nucleus

    E-Print Network [OSTI]

    Baye, D; Tursunov, E M

    2010-01-01T23:59:59.000Z

    The neutron-rich $^{11}$Li halo nucleus is unique among nuclei with known separation energies by its ability to emit a proton and a neutron in a $\\beta$ decay process. The branching ratio towards this rare decay mode is evaluated within a three-body model for the initial bound state and with Coulomb three-body final scattering states. The branching ratio should be comprised between two extreme cases, i.e.\\ a lower bound $6 \\times 10^{-12}$ obtained with a pure Coulomb wave and an upper bound $5 \\times 10^{-10}$ obtained with a plane wave. A simple model with modified Coulomb waves provides plausible values between between $0.8 \\times 10^{-10}$ and $2.2 \\times 10^{-10}$ with most probable total energies of the proton and neutron between 0.15 and 0.3 MeV.

  9. A unique decay process: beta delayed emission of a proton and a neutron by the $^{11}$Li halo nucleus

    E-Print Network [OSTI]

    D. Baye; P. Descouvemont; E. M. Tursunov

    2010-12-28T23:59:59.000Z

    The neutron-rich $^{11}$Li halo nucleus is unique among nuclei with known separation energies by its ability to emit a proton and a neutron in a $\\beta$ decay process. The branching ratio towards this rare decay mode is evaluated within a three-body model for the initial bound state and with Coulomb three-body final scattering states. The branching ratio should be comprised between two extreme cases, i.e.\\ a lower bound $6 \\times 10^{-12}$ obtained with a pure Coulomb wave and an upper bound $5 \\times 10^{-10}$ obtained with a plane wave. A simple model with modified Coulomb waves provides plausible values between between $0.8 \\times 10^{-10}$ and $2.2 \\times 10^{-10}$ with most probable total energies of the proton and neutron between 0.15 and 0.3 MeV.

  10. Control of emission wavelength for InGaAs/GaAs quantum wells and laser structures on their basis by means of proton irradiation

    SciTech Connect (OSTI)

    Akhlestina, S. A.; Vasil'ev, V. K.; Vikhrova, O. V., E-mail: vikhrova@nifti.unn.ru; Danilov, Yu. A.; Zvonkov, B. N.; Nekorkin, S. M. [Lobachevsky Nizhni Novgorod State University, Physicotechnical Research Institute (Russian Federation)

    2010-11-15T23:59:59.000Z

    Features of controlling the wavelength of emission from laser heterostructures with strained InGaAs/GaAs quantum wells by irradiation with medium-energy (with the energy as high as 150 keV) protons are studied. It is established that irradiation with H{sup +} ions and subsequent thermal annealing at a temperature of 700 deg. C make it possible to decrease the wavelength of emission from quantum wells. As the dose of ions is increased from 10{sup 13} to 10{sup 16} cm{sup -2}, the magnitude of change in the wavelength increases to 20 nm. Starting with a dose of 10{sup 15} cm{sup -2}, a significant decrease in the intensity of emission is observed. The optimum dose of H{sup +} ions (6 x 10{sup 14} cm{sup -2}) and annealing temperature (700 deg. C) for modifying the InGaAs/GaAs/InGaP laser structures are determined; it is shown that, in this case, one can obtain a shift of {approx}(8-10) nm for the wavelength of laser radiation with low losses in intensity with the quality of the surface of laser structures retained. The observed 'blue' shift is caused by implantation-stimulated processes of intermixing of the In and Ga atoms at the InGaAs/GaAs interface.

  11. Assessing Millisecond Proto-Magnetars as GRB Central Engines

    E-Print Network [OSTI]

    Todd A. Thompson

    2006-11-12T23:59:59.000Z

    Magnetars are a sizable subclass of the neutron star census. Their very high magnetic field strengths are thought to be a consequence of rapid (millisecond) rotation at birth in a successful core-collapse supernova. In their first tens of seconds of existence, magnetars transition from hot, extended ``proto-''magnetars to the cooled and magnetically-dominated objects we identify $\\sim10^4$ years later as Soft Gamma-ray Repeaters (SGRs) and Anamolous X-ray Pulsars (AXPs). Millisecond proto-magnetar winds during this cooling phase likewise transition from non-relativistic and thermally-driven to magneto-centrifugally-driven, and finally to relativistic and Poynting-flux dominated. Here we review the basic considerations associated with that transition. In particular, we discuss the spindown of millisecond proto-magnetars throughout the Kelvin-Helmholtz cooling epoch. Because of their large reservoir of rotational energy, their association with supernovae, and the fact that their winds are expected to become highly relativistic in the seconds after their birth, proto-magnetars have been suggested as the central engine of long-duration gamma ray bursts. We discuss some of the issues and outstanding questions in assessing them as such.

  12. Proton emission from cone-in-shell fast-ignition experiments at Omega N. Sinenian, W. Theobald, J. A. Frenje, C. Stoeckl, F. H. Sguin et al.

    E-Print Network [OSTI]

    for Laser Energetics, Rochester, New York 14623, USA 3 General Atomics, San Diego, California 92186, USA of energetic protons from cone-in-shell fast-igniton implosions at Omega have been conducted ) of energetic protons (7.5 MeV max.), indicating the presence of strong electric fields. These energetic protons

  13. Extension of the T{sub z} = {minus}3/2, A = 4n + 1 series of beta-delayed proton emitters to {sup 65}Se and {sup 73}Sr, and low energy beta-delayed proton emission from the T{sub z} = {minus}3/2, A = 4n + 3 nucleus {sup 23}Al

    SciTech Connect (OSTI)

    Batchelder, J.C.

    1993-12-01T23:59:59.000Z

    The series of known Tz = {minus}3/2, A = 4n + 1 nuclei has been extended to include the previously undiscovered isotopes {sup 65}Se and {sup 73}Sr, through the observation of beta-delayed proton emission via the isobaric analog state (IAS) of the beta-daughter (emitter). Due to the relatively large proton energies involved, these experiments were conducted using standard Si-Si {Delta}E-E telescopes. Beta-delayed protons arising from {sup 65}Se have been observed at an energy (laboratory) of 3.55 {plus_minus} 0.03 MeV, corresponding to the decay of the T = 3/2 isobaric analog state in {sup 65}As to the ground state of {sup 64}Ge. Similarly, beta-delayed protons from {sup 73}Sr at an energy of 3.75 {plus_minus} 0.04 MeV have been observed, corresponding to decay of the T = 3/2 isobaric analog state in {sup 73}Rb to the ground state of {sup 72}Kr. From the energies of these proton transitions, an improved prediction of the mass excesses of the two parent nuclei ({sup 65}Se and {sup 73}Sr) is made through the use of a Coulomb displacement formula. These predictions are {minus}33.41 {plus_minus} 0.26 and {minus}31.87 {plus_minus} 0.24 MeV for {sup 65}Se and {sup 73}Sr, respectively. Studies of low energy (down to {approximately}200 keV) beta-delayed protons from {sup 23}Al necessitated that a particle identification telescope with a low energy threshold for observation and identification of protons be developed. {sup 23}Al is of interest because of its role in the breakout of the hot CNO cycle leading to the astrophysical rp process.

  14. Far-Infrared ISO Limits on Dust Disks around Millisecond Pulsars

    E-Print Network [OSTI]

    T. J. W. Lazio; J. Fischer; R. S. Foster

    2001-09-26T23:59:59.000Z

    We report 60 and 90 micron observations of 7 millisecond pulsars with the ISOPHOT instrument and describe our analysis procedures. No pulsars were detected, and typical (3\\sigma) upper limits are 150 mJy. We combine our results with others in the literature and use them to place constraints on the existence of protoplanetary or dust disks around millisecond pulsars.

  15. Millisecond pulsar population in the Galactic center and high energy contributions

    E-Print Network [OSTI]

    W. Wang

    2005-10-15T23:59:59.000Z

    We propose that there possibly exists a population of millisecond pulsars in the Galactic center region. Millisecond pulsars (MSPs) could emit GeV gamma-rays through synchrotron-curvature radiation as predicted by outer gap models. In the same time, the compact wind nebulae around millisecond pulsars can emit X-rays though synchrotron radiation and TeV photons through inverse Compton processes. Besides, millisecond pulsar winds provide good candidates for the electron-positrons sources in the Galactic center. Therefore, we suggest that the millisecond pulsar population could contribute to the weak unidentified Chandra X-ray sources, the diffuse gamma-rays detected by EGRET, electron-positron annihilation lines and TeV photons detected by HESS toward the Galactic center.

  16. Scattering in the inner accretion disk and the waveforms and polarization of millisecond flux oscillations in LMXBs

    E-Print Network [OSTI]

    Sergei Y. Sazonov; Rashid A. Sunyaev

    2000-11-19T23:59:59.000Z

    The scattering by the inner accretion disk of X-ray radiation generated near the surface of a spinning neutron star in a low-mass X-ray binary (LMXB) has observable effects on the waveforms of millisecond X-ray flux oscillations produced e.g. during type-I bursts or in the millisecond pulsar SAX J1808.4--3658. We study these effects in the framework of a simplified model in which there is a single emitting spot on the stellar surface, which is visible both directly and in X-rays scattered from the disk. The main signature of scattering from a thin disk is that the pulse of scattered flux leads (if the star rotates in the same sense as the disk) or lags (in the contrary case) the primary pulse of direct emission by a quarter of a spin cycle. This is caused by Doppler boosting of radiation in the sub-relativistic Keplerian flow. The disk-scattered flux is revealed better in energy-resolved waveforms and the phase dependence of the polarized flux component. The phenomenon discussed permits direct testing of the presence of standard thin disks near the neutron stars in LMXBs and should be observable with future X-ray timing experiments having a few times better sensitivity than RXTE and also with sensitive X-ray polarimeters.

  17. Pulsed Gamma-Rays From the Millisecond Pulsar J0030+0451 with the Fermi Large Area Telescope

    SciTech Connect (OSTI)

    Abdo, Aous A.; /Naval Research Lab, Wash., D.C.; Ackermann, M.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Atwood, W.B.; /UC, Santa Cruz; Axelsson, M. /Stockholm U., OKC /Stockholm U.; Baldini, L.; /INFN, Pisa; Ballet, J.; /DAPNIA, Saclay; Barbiellini, Guido; /INFN, Trieste /Trieste U.; Bastieri, Denis; /INFN, Padua /Padua U.; Battelino, M.; /Stockholm U., OKC /Royal Inst. Tech., Stockholm; Baughman, B.M.; /Ohio State U.; Bechtol, K.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Bellazzini, R.; /INFN, Pisa; Berenji, B.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Bloom, Elliott D.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Bonamente, E.; /INFN, Perugia /Perugia U.; Borgland, A.W.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Bregeon, J.; /INFN, Pisa; Brez, A.; /INFN, Pisa; Brigida, M.; /Bari U. /INFN, Bari; Bruel, P.; /Ecole Polytechnique; Burnett, Thompson H.; /Washington U., Seattle /Bari U. /INFN, Bari /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /IASF, Milan /IASF, Milan /DAPNIA, Saclay /INFN, Perugia /Perugia U. /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /George Mason U. /Naval Research Lab, Wash., D.C. /NASA, Goddard /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /INFN, Perugia /Perugia U. /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /LPCE, Orleans /Montpellier U. /Sonoma State U. /Stockholm U., OKC /Royal Inst. Tech., Stockholm /Stockholm U. /ASDC, Frascati /Naval Research Lab, Wash., D.C. /INFN, Trieste /Bari U. /INFN, Bari /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /UC, Santa Cruz /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /CENBG, Gradignan /CENBG, Gradignan /Montpellier U. /Bari U. /INFN, Bari /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /INFN, Trieste /Hiroshima U.; /more authors..

    2011-11-17T23:59:59.000Z

    We report the discovery of gamma-ray pulsations from the nearby isolated millisecond pulsar PSR J0030+0451 with the Large Area Telescope (LAT) on the Fermi Gamma-ray Space Telescope (formerly GLAST). This discovery makes PSR J0030+0451 the second millisecond pulsar to be detected in gamma-rays after PSR J0218+4232, observed by the EGRET instrument on the Compton Gamma Ray Observatory. The spin-down power {dot E} = 3.5 x 10{sup 33} ergs s{sup -1} is an order of magnitude lower than the empirical lower bound of previously known gamma-ray pulsars. The emission profile is characterized by two narrow peaks, respectively 0.07 {+-} 0.01 and 0.08 {+-} 0.02 wide, separated by 0.44 {+-} 0.02 in phase. The first gamma-ray peak falls 0.15 {+-} 0.01 after the main radio peak. The pulse shape is similar to that of the 'normal' gamma-ray pulsars. An exponentially cut-off power-law fit of the emission spectrum leads to an integral photon flux above 100 MeV of (6.76 {+-} 1.05 {+-} 1.35) x 10{sup -8} cm{sup -2} s{sup -1} with cut-off energy (1.7 {+-} 0.4 {+-} 0.5) GeV. Based on its parallax distance of (300 {+-} 90) pc, we obtain a gamma-ray efficiency L{sub {gamma}}/{dot E} {approx_equal} 15% for the conversion of spin-down energy rate into gamma-ray radiation, assuming isotropic emission.

  18. The proton microquasar

    E-Print Network [OSTI]

    Gabriela S. Vila; Gustavo E. Romero

    2008-10-06T23:59:59.000Z

    We present a model for high-energy emission in microquasars where the energy content of the jets is dominated by relativistic protons. We also include a primary leptonic component. Particles are accelerated up to relativistic energies in a compact region located near the base of the jet, where most of the emission is produced. We calculate the production spectrum due to proton and electron synchrotron radiation and photohadronic interactions. The target field for proton-photon collisions is provided by the synchrotron radiation in the acceleration region. In models with a significant leptonic component, strong internal photon-photon absorption can attenuate the emission spectrum at high energies. Depending on the values of the parameters, our model predicts luminosities in the range 10^34-10^37 erg s^-1 up to GeV energies, with a high-energy tail that can extend up to 10^16 eV. In some cases, however, absorption effects can completely suppress the emission above 10 GeV, giving rise to different spectral shapes. These results can be tested in the near future by observations with instruments like GLAST-Fermi, HESS II and MAGIC II.

  19. Exploring the intrabinary shock from the redback millisecond pulsar PSR J2129-0429

    E-Print Network [OSTI]

    Hui, C Y; Park, S M; Takata, J; Li, K L; Tam, P H T; Lin, L C C; Kong, A K H; Cheng, K S; Kim, Chunglee

    2015-01-01T23:59:59.000Z

    We have investigated the intrabinary shock emission from the redback millisecond pulsar PSR J2129-0429 with XMM-Newton and Fermi. Orbital modulation in X-ray and UV can be clearly seen. Its X-ray modulation has a double-peak structure with a dip in between. The observed X-rays are non-thermal dominant which can be modeled by a power-law with a photon index of ~1.2. Intrabinary shock can be the origin of the observed X-rays. The UV light curve is resulted from the ellipsoidal modulation of the companion. Modeling the UV light curve prefers a large viewing angle. The heating effect of the UV light curve is found to be negligible which suggests the high energy radiation beam of PSR J2129-0429 does not direct toward its companion. On the other hand, no significant orbital modulation can be found in gamma-ray which suggests the majority of the gamma-rays come from the pulsar.

  20. RADIO DETECTION OF THE FERMI-LAT BLIND SEARCH MILLISECOND PULSAR J1311-3430

    SciTech Connect (OSTI)

    Ray, P. S.; Wood, K. S. [Space Science Division, Naval Research Laboratory, Washington, DC 20375-5352 (United States); Ransom, S. M. [National Radio Astronomy Observatory (NRAO), Charlottesville, VA 22903 (United States); Cheung, C. C. [National Academy of Sciences, Washington, DC 20001 (United States); Giroletti, M. [INAF Istituto di Radioastronomia, I-40129 Bologna (Italy); Cognard, I. [Laboratoire de Physique et Chimie de l'Environnement, LPCE UMR 6115 CNRS, F-45071 Orleans Cedex 02 (France); Camilo, F. [Columbia Astrophysics Laboratory, Columbia University, New York, NY 10027 (United States); Bhattacharyya, B. [Inter-University Centre for Astronomy and Astrophysics, Pune 411 007 (India); Roy, J. [National Centre for Radio Astrophysics, Tata Institute of Fundamental Research, Pune 411 007 (India); Romani, R. W.; Kerr, M. [W. W. Hansen Experimental Physics Laboratory, Kavli Institute for Particle Astrophysics and Cosmology, Department of Physics and SLAC National Accelerator Laboratory, Stanford University, Stanford, CA 94305 (United States); Ferrara, E. C. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Guillemot, L.; Kramer, M. [Max-Planck-Institut fuer Radioastronomie, Auf dem Huegel 69, D-53121 Bonn (Germany); Johnston, S.; Keith, M. [CSIRO Astronomy and Space Science, Australia Telescope National Facility, Epping NSW 1710 (Australia); Pletsch, H. J. [Max-Planck-Institut fuer Gravitationsphysik, Albert-Einstein-Institut, D-30167 Hannover (Germany); Saz Parkinson, P. M., E-mail: Paul.Ray@nrl.navy.mil [Santa Cruz Institute for Particle Physics, Department of Physics and Department of Astronomy and Astrophysics, University of California at Santa Cruz, Santa Cruz, CA 95064 (United States)

    2013-01-20T23:59:59.000Z

    We report the detection of radio emission from PSR J1311-3430, the first millisecond pulsar (MSP) discovered in a blind search of Fermi Large Area Telescope (LAT) gamma-ray data. We detected radio pulsations at 2 GHz, visible for <10% of {approx}4.5 hr of observations using the Green Bank Telescope (GBT). Observations at 5 GHz with the GBT and at several lower frequencies with Parkes, Nancay, and the Giant Metrewave Radio Telescope resulted in non-detections. We also report the faint detection of a steep spectrum continuum radio source (0.1 mJy at 5 GHz) in interferometric imaging observations with the Jansky Very Large Array. These detections demonstrate that PSR J1311-3430 is not radio quiet and provide additional evidence that radio-quiet MSPs are rare. The radio dispersion measure of 37.8 pc cm{sup -3} provides a distance estimate of 1.4 kpc for the system, yielding a gamma-ray efficiency of 30%, typical of LAT-detected MSPs. We see apparent excess delay in the radio pulses as the pulsar appears from eclipse and we speculate on possible mechanisms for the non-detections of the pulse at other orbital phases and observing frequencies.

  1. Lighthouses with two lights: burst oscillations from the accretion-powered millisecond pulsars

    E-Print Network [OSTI]

    Anna L. Watts

    2008-08-19T23:59:59.000Z

    The key contribution of the discovery of nuclear-powered pulsations from the accretion-powered millisecond pulsars (AMPs) has been the establishment of burst oscillation frequency as a reliable proxy for stellar spin rate. This has doubled the sample of rapidly-rotating accreting neutron stars and revealed the unexpected absence of any stars rotating near the break-up limit. The resulting `braking problem' is now a major concern for theorists, particularly given the possible role of gravitational wave emission in limiting spin. This, however, is not the only area where burst oscillations from the AMPs are having an impact. Burst oscillation timing is developing into a promising technique for verifying the level of spin variability in the AMPs (a topic of considerable debate). These sources also provide unique input to our efforts to understand the still-elusive burst oscillation mechanism. This is because they are the only stars where we can reliably gauge the role of uneven fuel deposition and, of course, the magnetic field.

  2. BRIGHT 'MERGER-NOVA' FROM THE REMNANT OF A NEUTRON STAR BINARY MERGER: A SIGNATURE OF A NEWLY BORN, MASSIVE, MILLISECOND MAGNETAR

    SciTech Connect (OSTI)

    Yu, Yun-Wei [Institute of Astrophysics, Central China Normal University, Wuhan 430079 (China)] [Institute of Astrophysics, Central China Normal University, Wuhan 430079 (China); Zhang, Bing; Gao, He, E-mail: yuyw@mail.ccnu.edu.cn, E-mail: zhang@physics.unlv.edu [Department of Physics and Astronomy, University of Nevada, Las Vegas, NV 89154 (United States)] [Department of Physics and Astronomy, University of Nevada, Las Vegas, NV 89154 (United States)

    2013-10-20T23:59:59.000Z

    A massive millisecond magnetar may survive the merger of a neutron star (NS) binary, which would continuously power the merger ejecta. We develop a generic dynamic model for the merger ejecta with energy injection from the central magnetar. The ejecta emission (the {sup m}erger-nova{sup )} powered by the magnetar peaks in the UV band and the peak of the light curve, progressively shifts to an earlier epoch with increasing frequency. A magnetar-powered merger-nova could have an optical peak brightness comparable to a supernova, which is a few tens or hundreds times brighter than the radioactive-powered merger-novae (the so-called macro-nova or kilo-nova). On the other hand, such a merger-nova would peak earlier and have a significantly shorter duration than that of a supernova. An early collapse of the magnetar could suppress the brightness of the optical emission and shorten its duration. Such millisecond-magnetar-powered merger-novae may be detected from NS-NS merger events without an observed short gamma-ray burst, and could be a bright electromagnetic counterpart for gravitational wave bursts due to NS-NS mergers. If detected, it suggests that the merger leaves behind a massive NS, which has important implications for the equation-of-state of nuclear matter.

  3. accreting millisecond pulsars: Topics by E-print Network

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

    pulsars formed by accretion induced collapse can be a source of cosmological gamma-ray bursts. We find that relativistic beaming of gamma-ray emission and precession of...

  4. accreting millisecond pulsar: Topics by E-print Network

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

    pulsars formed by accretion induced collapse can be a source of cosmological gamma-ray bursts. We find that relativistic beaming of gamma-ray emission and precession of...

  5. XMM-Newton Data Processing for Faint Diffuse Emission: Proton Flares, Exposure Maps and Report on EPIC MOS1 Bright CCDs Contamination

    E-Print Network [OSTI]

    J. Pradas; J. Kerp

    2005-08-04T23:59:59.000Z

    We present a study of the in-flight performance of the XMM-Newton EPIC MOS and pn detectors, with focus on the influence of proton flares and vignetting on the data. The very wide range in the conditions of our sample of observations, in terms of exposure length and background intensities, allows the detection of a wide range in the spectra of the proton flares, in contrast to the hard-spectrum flares proposed by Lumb et al.(2002) or Read et al.(2003) We also find an up to now unreported contamination in the low energy regime (Econtamination yields in "bright CCDs" in the observations. Its effect must be taken into account for the study of sources detected in the affected CCDs. With respect to vignetting, we present in-flight exposure maps and we propose a method to repeat this calculation for user-definable energy bands. All the results presented here, have the goal to enable the study of very faint extended sources with XMM-Newton, like nearby galactic X-ray halos or the soft X-ray background.

  6. Evolution from Canonical to Millisecond Pulsar through the X-ray Accretion Stage

    E-Print Network [OSTI]

    Norman K. Glendenning; Fridolin Weber

    2000-10-17T23:59:59.000Z

    We model the evolution of canonical pulsars from the death line to millisecond pulsars through the X-ray neutron star stage of accretion from a low-mass companion. We trace this evolution in magnetic field strength starting at $B=10^{12}$ to $10^8$ G and in period of about 1 s to milliseconds. Important factors are accretion rate and the decay rate of the magnetic field. A broad swathe is traced in the $B-P$ plane according to the value of these factors, which represent different conditions of the binary pair. An important ingredient is the dependence of the stellar moment of inertia on rotation frequency (time).

  7. A compact proton spectrometer for measurement of the absolute DD proton spectrum from which yield and R are determined in thin-shell inertial-confinement-fusion

    E-Print Network [OSTI]

    A compact proton spectrometer for measurement of the absolute DD proton spectrum from which yield for extending by 103 the dynamic range of compact proton spectrometers for diagnosing ICF implosions. Sci. Instrum. 85, 063502 (2014); 10.1063/1.4880203 D 3 He -proton emission imaging for inertial

  8. Proton radioactivity half lives with Skyrme interactions

    E-Print Network [OSTI]

    T. R. Routray; Abhishek Mishra; S. K. Tripathy; B. Behera; D. N. Basu

    2012-05-31T23:59:59.000Z

    The potential barrier impeding the spontaneous emission of protons in the proton radioactive nuclei is calculated as the sum of nuclear, Coulomb and centrifugal contributions. The nuclear part of the proton-nucleus interaction potential is obtained in the energy density formalism using Skyrme effective interaction that results into a simple algebraic expression. The half-lives of the proton emitters are calculated for the different Skyrme sets within the improved WKB framework. The results are found to be in reasonable agreement with the earlier results obtained for more complicated calculations involving finite range interactions.

  9. Nuclear-Powered Millisecond Pulsars and the Maximum Spin Frequency of Neutron Stars

    E-Print Network [OSTI]

    Deepto Chakrabarty; Edward H. Morgan; Michael P. Muno; Duncan K. Galloway; Rudy Wijnands; Michiel van der Klis; Craig B. Markwardt

    2003-07-01T23:59:59.000Z

    Millisecond pulsars are neutron stars (NSs) that are thought to have been spun-up by mass accretion from a stellar companion. It is unknown whether there is a natural brake for this process, or if it continues until the centrifugal breakup limit is reached at submillisecond periods. Many NSs that are accreting from a companion exhibit thermonuclear X-ray bursts that last tens of seconds, caused by unstable nuclear burning on their surfaces. Millisecond brightness oscillations during bursts from ten NSs (as distinct from other rapid X-ray variability that is also observed) are thought to measure the stellar spin, but direct proof of a rotational origin has been lacking. Here, we report the detection of burst oscillations at the known spin frequency of an accreting millisecond pulsar, and we show that these oscillations always have the same rotational phase. This firmly establishes burst oscillations as nuclear-powered pulsations tracing the spin of accreting NSs, corroborating earlier evidence. The distribution of spin frequencies of the 11 nuclear-powered pulsars cuts off well below the breakup frequency for most NS models, supporting theoretical predictions that gravitational radiation losses can limit accretion torques in spinning up millisecond pulsars.

  10. Millisecond switching in solid state electrochromic polymer devices fabricated from ionic self-assembled multilayers

    E-Print Network [OSTI]

    Heflin, Randy

    Millisecond switching in solid state electrochromic polymer devices fabricated from ionic self The electrochromic switching times of solid state conducting polymer devices fabricated by the ionic self shown to decrease with the active area of the electrochromic device suggesting that even faster

  11. Swinging between rotation and accretion power in a millisecond binary pulsar

    E-Print Network [OSTI]

    Papitto, A; Bozzo, E; Rea, N; Pavan, L; Campana, S; Romano, P; Burderi, L; Di Salvo, T; Riggio, A; Torres, D F; Falanga, M; Hessels, J W T; Burgay, M; Sarkissian, J M; Wieringa, M H; Filipovi?, M D; Wong, G F

    2013-01-01T23:59:59.000Z

    Radio pulsars are neutron stars that emit radiation modulated and powered by the rotation of their magnetic field, and which consequently decelerate (Pacini, 1967). The very fast millisecond spin periods measured in old radio pulsars (Backer et al. 1982) are thought to be the outcome of an earlier X-ray bright phase, during which the neutron star accretes matter and angular momentum from a low mass companion star in a binary system (Alpar et al. 1982; Radhakrishnan & Srinivasan 1982). This evolutionary scenario has been supported by the detection of X-ray millisecond pulsations from several accreting neutron stars in the past fifteen years (Wijnands & van der Klis 1998), as well as by the indirect evidence for the presence of a disk in the past around a millisecond radio pulsar now powered by rotation (Archibald et al. 2009). However, a transition between a rotation-powered and an accretion-powered state was never observed. Here we present the detection of millisecond X-ray pulsations from an accretin...

  12. Proton core imaging of the nuclear burn in inertial confinement fusion implosions

    E-Print Network [OSTI]

    Proton core imaging of the nuclear burn in inertial confinement fusion implosions J. L. De; published online 7 April 2006 A proton emission imaging system has been developed and used extensively the penetrating 14.7 MeV protons produced from D 3 He fusion reactions to produce emission images of the nuclear

  13. Proton radioactivity within a generalized liquid drop model J. M. Dong,1

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Proton radioactivity within a generalized liquid drop model J. M. Dong,1 H. F. Zhang,1 and G. Royer) The proton radioactivity half-lives of spherical proton emitters are investigated theoretically. The potential barriers preventing the emission of proton are determined in the quasimolecular shape path within

  14. Moving Protons with Pendant Amines: Proton Mobility in a Nickel...

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

    Moving Protons with Pendant Amines: Proton Mobility in a Nickel Catalyst for Oxidation of Hydrogen. Moving Protons with Pendant Amines: Proton Mobility in a Nickel Catalyst for...

  15. Testing the millisecond pulsar scenario of the Galactic center gamma-ray excess with very high energy gamma-rays

    E-Print Network [OSTI]

    Qiang Yuan; Kunihito Ioka

    2015-02-09T23:59:59.000Z

    The recent analyses of the Fermi Large Area Telescope data show an extended GeV $\\gamma$-ray excess on top of the expected diffuse background in the Galactic center region, which can be explained with annihilating dark matter or a population of millisecond pulsars (MSPs). We propose to observe the very high energy $\\gamma$-rays for distinguishing the MSP scenario from the dark matter scenario. The GeV $\\gamma$-ray MSPs should release most energy to the relativistic $e^{\\pm}$ wind, which will diffuse in the Galaxy and radiate TeV $\\gamma$-rays through inverse Compton scattering and bremsstrahlung processes. By calculating the spectrum and spatial distribution, we show that such emission is detectable with the next generation very high energy $\\gamma$-ray observatory, the Cherenkov Telescope Array (CTA), under reasonable model parameters. It is essential to search for the multi-wavelength counterparts to the GeV $\\gamma$-ray excess for solving this mystery in the high energy universe.

  16. FIVE NEW MILLISECOND PULSARS FROM A RADIO SURVEY OF 14 UNIDENTIFIED FERMI-LAT GAMMA-RAY SOURCES

    SciTech Connect (OSTI)

    Kerr, M. [W. W. Hansen Experimental Physics Laboratory, Kavli Institute for Particle Astrophysics and Cosmology, Department of Physics and SLAC National Accelerator Laboratory, Stanford University, Stanford, CA 94305 (United States); Camilo, F. [Columbia Astrophysics Laboratory, Columbia University, New York, NY 10027 (United States); Johnson, T. J. [National Academy of Sciences, Washington, DC 20001 (United States); Ferrara, E. C.; Harding, A. K. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Guillemot, L.; Kramer, M. [Max-Planck-Institut fuer Radioastronomie, Auf dem Huegel 69, 53121 Bonn (Germany); Hessels, J. [Netherlands Institute for Radio Astronomy (ASTRON), Postbus 2, 7990 AA Dwingeloo (Netherlands); Johnston, S.; Keith, M.; Reynolds, J. E. [CSIRO Astronomy and Space Science, Australia Telescope National Facility, Epping, NSW 1710 (Australia); Ransom, S. M. [National Radio Astronomy Observatory (NRAO), Charlottesville, VA 22903 (United States); Ray, P. S.; Wood, K. S. [Space Science Division, Naval Research Laboratory, Washington, DC 20375-5352 (United States); Sarkissian, J., E-mail: kerrm@stanford.edu, E-mail: fernando@astro.columbia.edu, E-mail: tyrel.j.johnson@gmail.com [CSIRO Parkes Observatory, Parkes, NSW 2870 (Australia)

    2012-03-20T23:59:59.000Z

    We have discovered five millisecond pulsars (MSPs) in a survey of 14 unidentified Fermi Large Area Telescope sources in the southern sky using the Parkes radio telescope. PSRs J0101-6422, J1514-4946, and J1902-5105 reside in binaries, while PSRs J1658-5324 and J1747-4036 are isolated. Using an ephemeris derived from timing observations of PSR J0101-6422 (P = 2.57 ms, DM = 12 pc cm{sup -3}), we have detected {gamma}-ray pulsations and measured its proper motion. Its {gamma}-ray spectrum (a power law of {Gamma} = 0.9 with a cutoff at 1.6 GeV) and efficiency are typical of other MSPs, but its radio and {gamma}-ray light curves challenge simple geometric models of emission. The high success rate of this survey-enabled by selecting {gamma}-ray sources based on their detailed spectral characteristics-and other similarly successful searches indicate that a substantial fraction of the local population of MSPs may soon be known.

  17. Coherence of burst oscillations and accretion-powered pulsations in the accreting millisecond pulsar XTE J1814-338

    E-Print Network [OSTI]

    Anna L. Watts; Alessandro Patruno; Michiel van der Klis

    2008-10-02T23:59:59.000Z

    X-ray timing of the accretion-powered pulsations during the 2003 outburst of the accreting millisecond pulsar XTE J1814-338 has revealed variation in the pulse time of arrival residuals. These can be interpreted in several ways, including spin-down and wandering of the fuel impact point around the magnetic pole. In this Letter we show that the burst oscillations of this source are coherent with the persistent pulsations, to the level where they track all of the observed fluctuations. Only one burst, which occurs at the lowest accretion rates, shows a significant phase offset. We discuss what might lead to such rigid phase-locking between the modulations in the accretion and thermonuclear burst emission, and consider the implications for spin variation and the burst oscillation mechanism. Wandering of the fuel impact hot spot around a fixed magnetic pole seems the most likely cause for the accretion-powered pulse phase variations. This means that the burst asymmetry is coupled to the hot spot, not the magnetic pole. If premature ignition at this point (due to higher local temperatures) triggers a burning front that stalls before spreading over the entire surface, the resulting localized nuclear hot spot may explain the unusual burst and burst oscillation properties of this source.

  18. Micro-PIXE (proton-induced X-ray emission) study of the effects of fluoride on mineral distribution patterns in enamel and dentin in the developing hamster tooth germ

    SciTech Connect (OSTI)

    Lyaruu, D.M.; Tros, G.H.; Bronckers, A.L.; Woeltgens, J.H. (ACTA, Amsterdam (Netherland))

    1990-06-01T23:59:59.000Z

    Micro-PIXE (proton-induced X-ray emission) analysis was performed on unfixed and anhydrously prepared sections from developing enamel and dentin from hamsters injected with a single dose of 20 mg NaF/kg body weight. Fluoride, apart from inducing the formation of the characteristic paired response in the enamel (i.e., a hyper- followed by a hypomineralized band in the secretory enamel), also induces the formation of sub-ameloblastic cystic lesions under the transitional and early secretory enamel accompanied by relatively intense hypermineralization of the underlying cystic enamel surface. These cystic lesions, however, were only found to be associated with certain isolated populations of these cells. In addition, these lesions were restricted to the smooth surfaces of the tooth germ only. Cystic lesions such as those seen under the transitional and early secretory ameloblasts were not observed under the fully secretory or maturation stage ameloblasts. Why fluoride induces the formation of cystic lesions in some ameloblast populations while other cells in the same stage of development apparently remain unaffected, is a matter which needs further investigation.

  19. Time-resolved temperature measurement and numerical simulation of millisecond laser irradiated silicon

    SciTech Connect (OSTI)

    Li Zewen; Zhang Hongchao; Shen Zhonghua; Ni Xiaowu [School of Science, Nanjing University of Science and Technology, Nanjing 210094 (China)

    2013-07-21T23:59:59.000Z

    Thermal process of 1064 nm millisecond pulsed Nd:YAG laser irradiated silicon was time-resolved temperature measured by an infrared radiation pyrometer, temperature evolutions of the spot center for wide range of laser energy densities were presented. The waveforms of temperature evolution curves contained much information about phase change, melting, solidification and vaporization. An axisymmetric numerical model was established for millisecond laser heating silicon. The transient temperature fields were obtained by using the finite element method. The numerical results of temperature evolutions of the spot center are in good agreement with the experimental results. Furthermore, the axial temperature distributions of the numerical results give a better understanding of the waveforms in the experimental results. The melting threshold, vaporizing threshold, melting duration, and melting depth were better identified by analyzing two kinds of results.

  20. A Tighter Constraint on post-Newtonian Gravity using Millisecond Pulsars

    E-Print Network [OSTI]

    J. F. Bell

    1995-08-08T23:59:59.000Z

    Some theories of gravity predict the existence of preferred-frame effects and violations of conservation of energy and momentum. General relativity predicts no such effects. In the parameterised post-Newtonian (PPN) formalism, the parameter, \\al3 $\\equiv 0$ if these effects do not exist. The period derivatives ($\\dot{P}$) of millisecond pulsars (MSPs) are used to more tightly constrain these effects by showing that $|$\\al3$|$ $< 5 \\times 10^{-16}$.

  1. Temporal variations in space-time and progenitors of gamma ray burst and millisecond pulsars

    E-Print Network [OSTI]

    Preston Jones

    2007-08-31T23:59:59.000Z

    A time varying space-time metric is shown to be a source of electromagnetic radiation. The post-Newtonian approximation is used as a realistic model of the connection between the space-time metric and a time varying gravitational potential. Large temporal variations in the metric from the coalescence of colliding black holes and neutron stars are shown to be possible progenitors of gamma ray burst and millisecond pulsars.

  2. Millisecond Kinetics of Nanocrystal Cation Exchange UsingMicrofluidic X-ray Absorption Spectroscopy

    SciTech Connect (OSTI)

    Chan, Emory M.; Marcus, Matthew A.; Fakra, Sirine; Elnaggar,Mariam S.; Mathies, Richard A.; Alivisatos, A. Paul

    2007-05-07T23:59:59.000Z

    We describe the use of a flow-focusing microfluidic reactorto measure the kinetics of theCdSe-to-Ag2Se nanocrystal cation exchangereaction using micro-X-ray absorption spectroscopy (mu XAS). The smallmicroreactor dimensions facilitate the millisecond mixing of CdSenanocrystal and Ag+ reactant solutions, and the transposition of thereaction time onto spatial coordinates enables the in situ observation ofthe millisecond reaction with mu XAS. XAS spectra show the progression ofCdSe nanocrystals to Ag2Se over the course of 100 ms without the presenceof long-lived intermediates. These results, along with supporting stoppedflow absorption experiments, suggest that this nanocrystal cationexchange reaction is highly efficient and provide insight into how thereaction progresses in individual particles. This experiment illustratesthe value and potential of in situ microfluidic X-ray synchrotrontechniques for detailed studies of the millisecond structuraltransformations of nanoparticles and other solution-phase reactions inwhich diffusive mixing initiates changes in local bond structures oroxidation states.

  3. Proton Therapy - Accelerating Protons to Save Lives

    SciTech Connect (OSTI)

    Keppel, Cynthia (Hampton University Proton Therapy) [Hampton University Proton Therapy

    2011-10-25T23:59:59.000Z

    In 1946, physicist Robert Wilson first suggested that protons could be used as a form of radiation therapy in the treatment of cancer because of the sharp drop-off that occurs on the distal edge of the radiation dose. Research soon confirmed that high-energy protons were particularly suitable for treating tumors near critical structures, such as the heart and spinal column. The precision with which protons can be delivered means that more radiation can be deposited into the tumor while the surrounding healthy tissue receives substantially less or, in some cases, no radiation. Since these times, particle accelerators have continuously been used in cancer therapy and today new facilities specifically designed for proton therapy are being built in many countries. Proton therapy has been hailed as a revolutionary cancer treatment, with higher cure rates and fewer side effects than traditional X-ray photon radiation therapy. Proton therapy is the modality of choice for treating certain small tumors of the eye, head or neck. Because it exposes less of the tissue surrounding a tumor to the dosage, proton therapy lowers the risk of secondary cancers later in life - especially important for young children. To date, over 80,000 patients worldwide have been treated with protons. Currently, there are nine proton radiation therapy facilities operating in the United States, one at the Hampton University Proton Therapy Institute. An overview of the treatment technology and this new center will be presented.

  4. Proton structure and tensor gluons

    E-Print Network [OSTI]

    George Savvidy

    2014-07-31T23:59:59.000Z

    We consider a possibility that inside the proton and, more generally, inside the hadrons there are additional partons - tensor-gluons, which can carry a part of the proton momentum. The tensor-gluons have zero electric charge, like gluons, but have a larger spin. Inside the proton a nonzero density of the tensor-gluons can be generated by the emission of tensor-gluons by gluons. The last mechanism is typical for non-Abelian tensor gauge theories, in which there exists a gluon-tensor-tensor vertex of order g. Therefore the number of gluons changes not only because a quark may radiate a gluon or because a gluon may split into a quark-antiquark pair or into two gluons, but also because a gluon can split into two tensor-gluons. The process of gluon splitting suggests that part of the proton momentum which was carried by neutral partons is shared between vector and tensor gluons. We derive evolution equations for the parton distribution functions which take into account these new processes. The momentum sum rule allows to find the tensor-gluons contribution to the Callan-Simanzik beta function and to calculate the corresponding anomalous dimensions. This contribution changes the behavior of the structure functions, and the logarithmic correction to the Bjorken scaling becomes more mild. This also influences the unification scale at which the coupling constants of the Standard Model merge, shifting its value to lower energies of order of 40 TeV.

  5. Proton Angular Distribution for 90 Mev Neutron-proton Scattering

    E-Print Network [OSTI]

    Hadley, James

    2010-01-01T23:59:59.000Z

    recoil protons in neutron -proton scattering at 90 Mev hasFOR 90 lWEV NEUTRON-PROTON SCATTERING James Hadley, Cecil E.

  6. Fine Structure Studies in Proton Emission

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField8,Dist.New MexicoFinancing Opportunities for RenewableSeriesStructure

  7. What the Timing of Millisecond Pulsars Can Teach us about Their Interior

    E-Print Network [OSTI]

    Mark G. Alford; Kai Schwenzer

    2014-12-08T23:59:59.000Z

    The cores of compact stars reach the highest densities in nature and therefore could consist of novel phases of matter. We demonstrate via a detailed analysis of pulsar evolution that precise pulsar timing data can constrain the star's composition, through unstable global oscillations (r-modes) whose damping is determined by microscopic properties of the interior. If not efficiently damped, these modes emit gravitational waves that quickly spin down a millisecond pulsar. As a first application of this general method, we find that ungapped interacting quark matter is consistent with both the observed radio and x-ray data, whereas for ordinary nuclear matter some additional enhanced damping mechanism is required.

  8. Laser-induced damage threshold of silicon in millisecond, nanosecond, and picosecond regimes

    SciTech Connect (OSTI)

    Wang, X.; Shen, Z. H.; Lu, J.; Ni, X. W. [School of Science, Nanjing University of Science and Technology, Nanjing 210094 (China)

    2010-08-15T23:59:59.000Z

    Millisecond, nanosecond, and picosecond laser pulse induced damage thresholds on single-crystal are investigated in this study. The thresholds of laser-induced damage on silicon are calculated theoretically for three pulse widths based on the thermal damage model. An axisymmetric mathematical model is established for the transient temperature field of the silicon. Experiments are performed to test the damage thresholds of silicon at various pulse widths. The results indicate that the damage thresholds obviously increase with the increasing of laser pulse width. Additionally, the experimental results agree well with theoretical calculations and numerical simulation results.

  9. Modeling the observed proton aurora and ionospheric convection responses to changes in the IMF clock angle

    E-Print Network [OSTI]

    Lockwood, Mike

    Modeling the observed proton aurora and ionospheric convection responses to changes in the IMF clock angle: 1. Persistence of cusp proton aurora K. Throp, M. Lockwood,1 B. S. Lanchester, and S. K employ a numerical model of cusp ion precipitation and proton aurora emission to fit variations

  10. Proton transport model in the ionosphere. 2. Inuence of magnetic mirroring and collisions

    E-Print Network [OSTI]

    Lummerzheim, Dirk

    Proton transport model in the ionosphere. 2. In¯uence of magnetic mirroring and collisions on the angular redistribution in a proton beam M. Galand1 , J. Lilensten2 , W. Kofman2 , D. Lummerzheim3 1 High in a proton/hydrogen beam by using a transport code in comparison with observations. H-emission Doppler pro

  11. TRANSVERSE ELECTRON-PROTON TWO-STREAM INSTABILITY IN A BUNCHED BEAM

    SciTech Connect (OSTI)

    Wang, T. F. (Tai-Sen F.); Channell, Paul J.; Macek, R. J. (Robert J.); Davidson, Ronald C.

    2001-01-01T23:59:59.000Z

    For intense proton beams, the focus of recent two-stream instability analyses has been on the transverse instability observed in the Proton Storage Ring (PSR) at Los Alamos National Laboratory. The PSR stores a long proton bunch with a near triangular line density profile for a duration of about one millisecond. The instability is observed as rapidly growing transverse oscillations of the stored beam, usually occuring when the beam intensity reaches 2.5 x 10{sup 13} ppp or higher, causing fast beam loss. Experimental results support the conjecture that the instability in PSR is due to the two-stream interaction between the circulating proton beam and the electrons created in the ring, i.e., the so called e-p instability. However, the understanding of the physics of this instability is usually based on the theory developed for a continuous beam of uniform line density. Although computer simulations have been implemented or are being developed to study the e-p instability in bunched beams, a companion analytical theory still remains to be developed. The present work is an attempt to investigate the transverse e-p instability in a proton bunch using an analytical approach based on the centroid model built on the 'one-pass' interaction between the protons and the electrons. This paper is an analytical investigation of the transverse electron-proton (e-p) two-stream instability in a proton bunch propagating through a stationary electron background. The equations of motion, including the effect of damping, are derived for the centroids of the proton beam and the electron cloud. An approach is developed to solve the coupled linear centroid equations in the time domain describing the e-p instability in proton bunches with nonuniform line densities. Examples are presented for proton line densities corresponding to uniform and parabolic profiles.

  12. What's In a Proton?

    ScienceCinema (OSTI)

    Brookhaven Lab

    2010-01-08T23:59:59.000Z

    Physicist Peter Steinberg explains that fundamental particles like protons are themselves made up of still smaller particles called quarks. He discusses how new particles are produced when quarks are liberated from protons...a process that can be observed

  13. Particle production in proton-proton collisions

    E-Print Network [OSTI]

    M. T. Ghoneim; M. T. Hussein; F. H. Sawy

    2014-10-27T23:59:59.000Z

    In this work, we present a study of particle production in proton-proton collisions using data that are collected from many experiments of relative wide range of reaction energies. These data include production of pions and heavier particles; like keons and lambda hyperons. Proton-proton collision is a simple system to investigate and to be considered a starting point that guides to more complicated processes of production in the proton-nucleus and the nucleus-nucleus collisions. In this paper, we are interested in the mechanisms that describe the process of particle production over a wide range of interaction energy, and how the physics of production changes with changing energy. Besides, this work may raise a question: are heavier particles than pions produced via the same mechanism(s) of producing pions, or these are created differently, being different in masses and other physical properties?

  14. Numerical and experimental study of the thermal stress of silicon induced by a millisecond laser

    SciTech Connect (OSTI)

    Wang Xi; Qin Yuan; Wang Bin; Zhang Liang; Shen Zhonghua; Lu Jian; Ni Xiaowu

    2011-07-20T23:59:59.000Z

    A spatial axisymmetric finite element model of single-crystal silicon irradiated by a 1064 nm millisecond laser is used to investigate the thermal stress damage induced by a millisecond laser. The transient temperature field and the thermal stress field for 2 ms laser irradiation with a laser fluence of 254 J/cm{sup 2} are obtained. The numerical simulation results indicate that the hoop stresses along the r axis on the front surface are compressive stress within the laser spot and convert to tensile stress outside the laser spot, while the radial stresses along the r axis on the front surface and on the z axis are compressive stress. The temperature of the irradiated center is the highest temperature obtained, yet the stress is not always highest during laser irradiation. At the end of the laser irradiation, the maximal hoop stress is located at r=0.5 mm and the maximal radial stress is located at r=0.76 mm. The temperature measurement experiments are performed by IR pyrometer. The numerical result of the temperature field is consistent with the experimental result. The damage morphologies of silicon under the action of a 254 J/cm{sup 2} laser are inspected by optical microscope. The cracks are observed initiating at r=0.5 mm and extending along the radial direction.

  15. The X-ray afterglow flat segment in short GRB 051221A: Energy injection from a millisecond magnetar?

    E-Print Network [OSTI]

    Yizhong Fan; Dong Xu

    2006-07-12T23:59:59.000Z

    The flat segment lasting $\\sim 10^4$ seconds in the X-ray afterglow of GRB051221A represents the first clear case of strong energy injection in the external shock of a short GRB afterglow. In this work, we show that a millisecond pulsar with dipole magnetic field $\\sim 10^{14}$ Gauss could well account for that energy injection. The good quality X-ray flat segment thus suggests that the central engine of this short burst may be a millisecond magnetar.

  16. Excitation of a nonradial mode in a millisecond X-ray pulsar XTE J1751-305

    E-Print Network [OSTI]

    Lee, Umin

    2014-01-01T23:59:59.000Z

    We discuss candidates for non-radial modes excited in a mass accreting and rapidly rotating neutron star to explain the coherent frequency identified in the light curves of a millisecond X-ray pulsar XTE J1751-305. The spin frequency of the pulsar is $\

  17. Quick extended x-ray absorption fine structure instrument with millisecond time scale, optimized for in situ applications

    E-Print Network [OSTI]

    Sparks, Donald L.

    Quick extended x-ray absorption fine structure instrument with millisecond time scale, optimized of quick extended x-ray absorption fine structure QEXAFS and quick x-ray absorption near edge structure- tion spectroscopy XAS was developed in energy dispersive and quick extended x-ray absorption fine

  18. Broadband proton-decoupled proton spectra Andrew J. Pell

    E-Print Network [OSTI]

    Keeler, James

    Broadband proton-decoupled proton spectra Andrew J. Pell , Richard A. E. Edden§ and James Keeler.ac.uk. #12;Abstract We present a new method for recording broadband proton-decoupled proton spectra with ab reduction in sensitivity when com- pared to a conventional proton spectrum. The method is demonstrated

  19. Electromagetic proton form factors

    E-Print Network [OSTI]

    M Y Hussein

    2006-10-31T23:59:59.000Z

    The electromagnetic form factors are crucial to our understanding of the proton internal structure, and thus provide a strong constraint of the distributions of the charge and magnetization current within the proton. We adopted the quark-parton model for calculating and understanding the charge structure of the proton interms of the electromagnetic form factors. A remarkable agreement with the available experimental evidence is found.

  20. Proton-Antiproton

    ScienceCinema (OSTI)

    None

    2011-04-25T23:59:59.000Z

    Dernière session du cours sur proton-antiproton du Cern Accelarator School. John Peoples, directeur de Fermilab fait un exposà suivi de questions.

  1. Deformed proton emitters.

    SciTech Connect (OSTI)

    Carpenter, M. P.; Cizewski, J. A.; Davids, C. N.; Davinson, T.; Fotiades, N.; Henderson, D. J.; Janssens, R. V. F.; Lauritsen, T.; Reiter, P.; Ressler, J. J.; Schwartz, J.; Seweryniak, D.; Sonzogni, A. A.; Uusitalok, J.; Walters, W. B.; Wiedenhover, I. L.; Woods, P. J.

    1999-02-17T23:59:59.000Z

    The mechanisms of proton radioactivity from deformed rare earth nuclei are discussed and preliminary results on the fine structure decay of {sup 131}Eu are presented.

  2. Proton Angular Distribution for 90 Mev Neutron-proton Scattering

    E-Print Network [OSTI]

    Hadley, James

    2010-01-01T23:59:59.000Z

    3, 1947 The angular distribution of the recoil protons inneutron -proton scattering at 90 Mev has been measured forNO. W ..7405-Eng 48 PROTON .ANGULAR DISTRIBUTION FOR 90 lWEV

  3. Proton-Proton Scattering at 340 MeV

    E-Print Network [OSTI]

    Chamberlain, Owen; Wiegand, Clyde

    2008-01-01T23:59:59.000Z

    on Nuclear Physics. Basil. High yner gy Neutron- protonand Proton~proton Scattering 9 Helv. Phys. Acta (in press J a review

  4. INFRARED OBSERVATIONS OF THE MILLISECOND PULSAR BINARY J1023+0038: EVIDENCE FOR THE SHORT-TERM NATURE OF ITS INTERACTING PHASE IN 2000-2001

    SciTech Connect (OSTI)

    Wang, Xuebing; Wang, Zhongxiang [Key Laboratory for Research in Galaxies and Cosmology, Shanghai Astronomical Observatory, Chinese Academy of Sciences, 80 Nandan Road, Shanghai 200030 (China)] [Key Laboratory for Research in Galaxies and Cosmology, Shanghai Astronomical Observatory, Chinese Academy of Sciences, 80 Nandan Road, Shanghai 200030 (China); Morrell, Nidia [Las Campanas Observatory, Observatories of the Carnegie Institution of Washington, La Serena (Chile)] [Las Campanas Observatory, Observatories of the Carnegie Institution of Washington, La Serena (Chile)

    2013-02-20T23:59:59.000Z

    We report our multi-band infrared (IR) imaging of the transitional millisecond pulsar system J1023+0038, a rare pulsar binary known to have an accretion disk in 2000-2001. The observations were carried out with ground-based and space telescopes from near-IR to far-IR wavelengths. We detected the source in near-IR JH bands and Spitzer 3.6 and 4.5 {mu}m mid-IR channels. Combined with the previously reported optical spectrum of the source, the IR emission is found to arise from the companion star, with no excess emission detected in the wavelength range. Because our near-IR fluxes are nearly equal to those obtained by the 2MASS all-sky survey in 2000 February, the result indicates that the binary did not contain the accretion disk at the time, whose existence would have raised the near-IR fluxes to twice larger values. Our observations have thus established the short-term nature of the interacting phase seen in 2000-2001: the accretion disk existed for at most 2.5 yr. The binary was not detected by the WISE all-sky survey carried out in 2010 at its 12 and 22 {mu}m bands and our Herschel far-IR imaging at 70 and 160 {mu}m. Depending on the assumed properties of the dust, the resulting flux upper limits provide a constraint of <3 Multiplication-Sign 10{sup 22}-3 Multiplication-Sign 10{sup 25} g on the mass of the dust grains that possibly exist as the remnants of the previously seen accretion disk.

  5. Proton-proton colliding beam facility ISABELLE

    SciTech Connect (OSTI)

    Hahn, H

    1980-01-01T23:59:59.000Z

    This paper attempts to present the status of the ISABELLE construction project, which has the objective of building a 400 + 400 GeV proton colliding beam facility. The major technical features of the superconducting accelerators with their projected performance are described. Progress made so far, difficulties encountered, and the program until completion in 1986 is briefly reviewed.

  6. Proton radioactivity within a generalized liquid drop model

    E-Print Network [OSTI]

    J. M. Dong; H. F. Zhang; G. Royer

    2009-06-02T23:59:59.000Z

    The proton radioactivity half-lives of spherical proton emitters are investigated theoretically. The potential barriers preventing the emission of protons are determined in the quasimolecular shape path within a generalized liquid drop model (GLDM) including the proximity effects between nuclei in a neck and the mass and charge asymmetry. The penetrability is calculated with the WKB approximation. The spectroscopic factor has been taken into account in half-life calculation, which is obtained by employing the relativistic mean field (RMF) theory combined with the BCS method with the force NL3. The half-lives within the GLDM are compared with the experimental data and other theoretical values. The GLDM works quite well for spherical proton emitters when the spectroscopic factors are considered, indicating the necessity of introducing the spectroscopic factor and the success of the GLDM for proton emission. Finally, we present two formulas for proton emission half-life calculation similar to the Viola-Seaborg formulas and Royer's formulas of alpha decay.

  7. Tensor gluons and proton structure

    E-Print Network [OSTI]

    George Savvidy

    2014-12-14T23:59:59.000Z

    In a recent article we were considering a possibility that inside a proton and, more generally, inside hadrons there could be additional partons - tensor-gluons, which carry a part of the proton momentum. Tensor-gluons have zero electric charge, like gluons, but have a larger spin. Therefore we call them tensor-gluons. The nonzero density of tensor-gluons can be generated by the emission of tensor-gluons by gluons. Tensor-gluons can further split into the pairs of tensor-gluons through a different channels. To describe all these processes one should know the general splitting probabilities for tensor-gluons. These probabilities should fulfill very general symmetry relations, which we were able to resolve by introducing a splitting index. This approach allows to find out the general form of the splitting functions, to derive corresponding DGLAP evolution equations and to calculate the one-loop Callan-Simanzik beta function for tensor-gluons of a given spin. Our results provide a nontrivial consistency check of the theory and of the Callan-Simanzik beta function calculations, because the theory has a unique coupling constant and its high energy behavior should be universal for all particles of the spectrum. We argue that the contribution of all spins into the beta function vanishes leading to a conformal invariant theory at very high energies.

  8. Magnetic burial and the harmonic content of millisecond oscillations in thermonuclear X-ray bursts

    E-Print Network [OSTI]

    D. J. B. Payne; A. Melatos

    2006-07-11T23:59:59.000Z

    Matter accreting onto the magnetic poles of a neutron star spreads under gravity towards the magnetic equator, burying the polar magnetic field and compressing it into a narrow equatorial belt. Steady-state, Grad-Shafranov calculations with a self-consistent mass-flux distribution (and a semi-quantitative treatment of Ohmic diffusion) show that, for $\\Ma \\gtrsim 10^{-5}\\Msun$, the maximum field strength and latitudinal half-width of the equatorial magnetic belt are $B_{\\rm max} = 5.6\\times 10^{15} (\\Ma/10^{-4}\\Msun)^{0.32}$ G and $\\Delta\\theta = \\max[3^{\\circ} (\\Ma/10^{-4}\\Msun)^{-1.5},3^{\\circ} (\\Ma/10^{-4}\\Msun)^{0.5}(\\dot{M}_{\\rm a}/10^{-8}\\Msun {\\rm yr}^{-1})^{-0.5}]$ respectively, where $\\Ma$ is the total accreted mass and $\\dot{M}_{\\rm a}$ is the accretion rate. It is shown that the belt prevents north-south heat transport by conduction, convection, radiation, and ageostrophic shear. This may explain why millisecond oscillations observed in the tails of thermonuclear (type I) X-ray bursts in low-mass X-ray binaries are highly sinusoidal: the thermonuclear flame is sequestered in the magnetic hemisphere which ignites first. The model is also consistent with the occasional occurrence of closely spaced pairs of bursts. Time-dependent, ideal-magnetohydrodynamic simulations confirm that the equatorial belt is not disrupted by Parker and interchange instabilities.

  9. Proton Radius Puzzle 1 Muonic hydrogen and the proton radius

    E-Print Network [OSTI]

    Pachucki, Krzysztof

    Proton Radius Puzzle 1 Muonic hydrogen and the proton radius puzzle Randolf Pohl Max-681 Warsaw, Poland Key Words Laser Spectroscopy, Atomic Physics, Proton Structure, Exotic Atoms, Nuclear extraction of the proton radius by Pohl et al. from the mea- #12;Annu. Rev. Nucl. Part. Sci. 2013, Vol. 63

  10. Investigation of proton focusing and conversion efficiency for proton fast ignition

    E-Print Network [OSTI]

    Bartal, Teresa Jean

    2012-01-01T23:59:59.000Z

    2.2 Proton Acceleration . . . . . . . . . . . . . . . .plasma (LSP) simulations . . Proton Focusing and ConversionProton Focusing and Conversion Efficiency with Hemispherical

  11. Muon-proton Scattering

    E-Print Network [OSTI]

    E. Borie

    2013-02-05T23:59:59.000Z

    A recent proposal to measure the proton form factor by means of muon-proton scattering will use muons which are not ultrarelativistic (and also not nonrelativistic). The usual equations describing the scattering cross section use the approximation that the scattered lepton (usually an electron) is ultrarelativistic, with v/c approximately equal to 1. Here the cross section is calculated for all values of the energy. It agrees with the standard result in the appropriate limit.

  12. PSR J1723–2837: AN ECLIPSING BINARY RADIO MILLISECOND PULSAR

    SciTech Connect (OSTI)

    Crawford, Fronefield [Department of Physics and Astronomy, Franklin and Marshall College, P.O. Box 3003, Lancaster, PA 17604 (United States); Lyne, Andrew G. [Jodrell Bank Centre for Astrophysics, University of Manchester, Manchester M13 9PL (United Kingdom); Stairs, Ingrid H. [Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, BC V6T 1Z1 (Canada); Kaplan, David L. [Physics Department, University of Wisconsin - Milwaukee, Milwaukee, WI 53211 (United States); McLaughlin, Maura A.; Lorimer, Duncan R. [Department of Physics, West Virginia University, Morgantown, WV 26506 (United States); Freire, Paulo C. C.; Kramer, Michael [Max-Planck-Institut für Radioastronomie, auf dem Huegel 69, D-53121 Bonn (Germany); Burgay, Marta; D'Amico, Nichi; Possenti, Andrea [INAF - Osservatorio Astronomico di Cagliari, Poggio dei Pini, I-09012 Capoterra (Italy); Camilo, Fernando [Columbia Astrophysics Laboratory, Columbia University, New York, NY 10027 (United States); Faulkner, Andrew [Cavendish Laboratory, University of Cambridge, J. J. Thompson Avenue, Cambridge, CB3 0HE (United Kingdom); Manchester, Richard N. [CSIRO Astronomy and Space Science, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710 (Australia); Steeghs, Danny, E-mail: fcrawfor@fandm.edu [Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom)

    2013-10-10T23:59:59.000Z

    We present a study of PSR J1723–2837, an eclipsing, 1.86 ms millisecond binary radio pulsar discovered in the Parkes Multibeam survey. Radio timing indicates that the pulsar has a circular orbit with a 15 hr orbital period, a low-mass companion, and a measurable orbital period derivative. The eclipse fraction of ?15% during the pulsar's orbit is twice the Roche lobe size inferred for the companion. The timing behavior is significantly affected by unmodeled systematics of astrophysical origin, and higher-order orbital period derivatives are needed in the timing solution to account for these variations. We have identified the pulsar's (non-degenerate) companion using archival ultraviolet, optical, and infrared survey data and new optical photometry. Doppler shifts from optical spectroscopy confirm the star's association with the pulsar and indicate a pulsar-to-companion mass ratio of 3.3 ± 0.5, corresponding to a companion mass range of 0.4 to 0.7 M{sub ?} and an orbital inclination angle range of between 30° and 41°, assuming a pulsar mass range of 1.4-2.0 M{sub ?}. Spectroscopy indicates a spectral type of G for the companion and an inferred Roche-lobe-filling distance that is consistent with the distance estimated from radio dispersion. The features of PSR J1723–2837 indicate that it is likely a 'redback' system. Unlike the five other Galactic redbacks discovered to date, PSR J1723–2837 has not been detected as a ?-ray source with Fermi. This may be due to an intrinsic spin-down luminosity that is much smaller than the measured value if the unmeasured contribution from proper motion is large.

  13. Proton Exchange Membrane Fuel Cells for Electrical Power Generation On-Board Commercial Airplanes

    Fuel Cell Technologies Publication and Product Library (EERE)

    Deployed on a commercial airplane, proton exchange membrane fuel cells may offer emissions reductions, thermal efficiency gains, and enable locating the power near the point of use. This work seeks to

  14. Imaging Sources with Fast and Slow Emission Components

    E-Print Network [OSTI]

    G. Verde; D. A. Brown; P. Danielewicz; C. K. Gelbke; W. G. Lynch; M. B. Tsang

    2001-12-15T23:59:59.000Z

    We investigate two-proton correlation functions for reactions in which fast dynamical and slow evaporative proton emission are both present. In such cases, the width of the correlation peak provides the most reliable information about the source size of the fast dynamical component. The maximum of the correlation function is sensitive to the relative yields from the slow and fast emission components. Numerically inverting the correlation function allows one to accurately disentangle fast dynamical from slow evaporative emission and extract details of the shape of the two-proton source.

  15. Proton Exchange Membranes for Fuel Cells

    SciTech Connect (OSTI)

    Devanathan, Ramaswami

    2010-11-01T23:59:59.000Z

    Proton exchange membrane, also known as polymer electrolyte membrane, fuel cells (PEMFCs) offer the promise of efficient conversion of chemical energy of fuel, such as hydrogen or methanol, into electricity with minimal pollution. Their widespread use to power zero-emission automobiles as part of a hydrogen economy can contribute to enhanced energy security and reduction in greenhouse gas emissions. However, the commercial viability of PEMFC technology is hindered by high cost associated with the membrane electrode assembly (MEA) and poor membrane durability under prolonged operation at elevated temperature. Membranes for automotive fuel cell applications need to perform well over a period comparable to the life of an automotive engine and under heavy load cycling including start-stop cycling under sub-freezing conditions. The combination of elevated temperature, changes in humidity levels, physical stresses and harsh chemical environment contribute to membrane degradation. Perfluorinated sulfonic acid (PFSA)-based membranes, such as Nafion®, have been the mainstay of PEMFC technology. Their limitations, in terms of cost and poor conductivity at low hydration, have led to continuing research into membranes that have good proton conductivity at elevated temperatures above 120 °C and under low humidity conditions. Such membranes have the potential to avoid catalyst poisoning, simplify fuel cell design and reduce the cost of fuel cells. Hydrocarbon-based membranes are being developed as alternatives to PFSA membranes, but concerns about chemical and mechanical stability and durability remain. Novel anhydrous membranes based on polymer gels infused with protic ionic liquids have also been recently proposed, but considerable fundamental research is needed to understand proton transport in novel membranes and evaluate durability under fuel cell operating conditions. In order to advance this promising technology, it is essential to rationally design the next generation of PEMs based on an understanding of chemistry, membrane morphology and proton transport obtained from experiment, theory and computer simulation.

  16. Studies of Charged Particle Emission in the Decay of 45Fe

    SciTech Connect (OSTI)

    Miernik, K. [University of Warsaw; Dominik, W. [University of Warsaw; Janas, Z. [University of Warsaw; Pfutzner, M. [University of Warsaw; Grigorenko, L. [Joint Institute for Nuclear Research, Dubna, Russia; Bingham, C. R. [University of Tennessee, Knoxville (UTK); Czyrkowski, H. [University of Warsaw; Cwiok, Mikolaj [Warsaw University; Darby, Iain [University of Tennessee, Knoxville (UTK); Dabrowski, Ryszard [Warsaw University; Ginter, T. N. [Michigan State University, East Lansing; Grzywacz, R. [University of Tennessee, Knoxville (UTK); Karny, M. [University of Warsaw; Korgul, A. [University of Warsaw; Kusmierz, W. [University of Warsaw; Liddick, Sean [University of Tennessee, Knoxville (UTK); Rajabali, M. M. [University of Tennessee, Knoxville (UTK); Rykaczewski, Krzysztof Piotr [ORNL; Stolz, A. [Michigan State University, East Lansing

    2008-01-01T23:59:59.000Z

    The decay of extremely neutron-deficient isotope 45Fe has been studied by using a new type of gaseous detector in which a technique of optical imaging is used to record tracks of charged particles. The two-proton radioactivity and the -decay channels accompanied by proton(s) emission were clearly identified. For the first time, the angular and energy correlations between two protons emitted from the 45Fe ground-state were measured. The obtained distributions were confronted with predictions of a three-body model. Studies of -decay channels of 45Fe provided first unambiguous evidence for the -delayed three proton emission.

  17. \\b{eta}-delayed three-proton decay of 31Ar

    E-Print Network [OSTI]

    Lis, A A; Dominik, W; Janas, Z; Pfützner, M; Pomorski, M; Acosta, L; Baraeva, S; Casarejos, E; Duénas-Díaz, J; Dunin, V; Espino, J M; Estrade, A; Farinon, F; Fomichev, A; Geissel, H; Gorshkov, A; Kami?ski, G; Kiselev, O; Knöbel, R; Krupko, S; Kuich, M; Litvinov, Yu A; Marquinez-Durán, G; Martel, I; Mukha, I; Nociforo, C; Ordúz, A K; Pietri, S; Prochazka, A; Sánchez-Benítez, A M; Simon, H; Sitar, B; Slepnev, R; Stanoiu, M; Strmen, P; Szarka, I; Takechi, M; Tanaka, Y; Weick, H; Winfield, J S

    2015-01-01T23:59:59.000Z

    The beta decay of 31Ar, produced by fragmentation of a 36Ar beam at 880 MeV/nucleon, was investigated. Identified ions of 31Ar were stopped in a gaseous time projection chamber with optical readout allowing to record decay events with emission of protons. In addition to \\b{eta}-delayed emission of one and two protons we have clearly observed the beta-delayed three-proton branch. The branching ratio for this channel in 31Ar is found to be 0.07(2)%.

  18. \\b{eta}-delayed three-proton decay of 31Ar

    E-Print Network [OSTI]

    A. A. Lis; C. Mazzocchi; W. Dominik; Z. Janas; M. Pfützner; M. Pomorski; L. Acosta; S. Baraeva; E. Casarejos; J. Duénas-Díaz; V. Dunin; J. M. Espino; A. Estrade; F. Farinon; A. Fomichev; H. Geissel; A. Gorshkov; G. Kami?ski; O. Kiselev; R. Knöbel; S. Krupko; M. Kuich; Yu. A. Litvinov; G. Marquinez-Durán; I. Martel; I. Mukha; C. Nociforo; A. K. Ordúz; S. Pietri; A. Prochazka; A. M. Sánchez-Benítez; H. Simon; B. Sitar; R. Slepnev; M. Stanoiu; P. Strmen; I. Szarka; M. Takechi; Y. Tanaka; H. Weick; J. S. Winfield

    2015-05-29T23:59:59.000Z

    The beta decay of 31Ar, produced by fragmentation of a 36Ar beam at 880 MeV/nucleon, was investigated. Identified ions of 31Ar were stopped in a gaseous time projection chamber with optical readout allowing to record decay events with emission of protons. In addition to \\b{eta}-delayed emission of one and two protons we have clearly observed the beta-delayed three-proton branch. The branching ratio for this channel in 31Ar is found to be 0.07(2)%.

  19. On the Proton charge extensions

    E-Print Network [OSTI]

    M. Gluck

    2015-02-03T23:59:59.000Z

    It is shown that the recent determination of the various proton charge extensions is compatible with Standard Model expectations.

  20. Proton Transfer and Proton Concentrations in Protonated Nafion Fuel Cell Membranes D. B. Spry and M. D. Fayer*

    E-Print Network [OSTI]

    Fayer, Michael D.

    Proton Transfer and Proton Concentrations in Protonated Nafion Fuel Cell Membranes D. B. Spry and M 21, 2009; ReVised Manuscript ReceiVed: June 3, 2009 Proton transfer in protonated Nafion fuel cell membranes is studied using several pyrene derivative photoacids. Proton transfer in the center of the Nafion

  1. SPIN EVOLUTION OF MILLISECOND MAGNETARS WITH HYPERACCRETING FALLBACK DISKS: IMPLICATIONS FOR EARLY AFTERGLOWS OF GAMMA-RAY BURSTS

    SciTech Connect (OSTI)

    Dai, Z. G.; Liu Ruoyu, E-mail: dzg@nju.edu.cn, E-mail: ryliu@nju.edu.cn [School of Astronomy and Space Science, Nanjing University, Nanjing 210093 (China)

    2012-11-01T23:59:59.000Z

    The shallow decay phase or plateau phase of early afterglows of gamma-ray bursts (GRBs), discovered by Swift, is currently understood as being due to energy injection to a relativistic blast wave. One natural scenario for energy injection invokes a millisecond magnetar as the central engine of GRBs because the conventional model of a pulsar predicts a nearly constant magnetic-dipole-radiation luminosity within the spin-down timescale. However, we note that significant brightening occurs in some early afterglows, which apparently conflicts with the above scenario. Here we propose a new model to explain this significant brightening phenomena by considering a hyperaccreting fallback disk around a newborn millisecond magnetar. We show that for typical values of the model parameters, sufficient angular momentum of the accreted matter is transferred to the magnetar and spins it up. It is this spin-up that leads to a dramatic increase of the magnetic-dipole-radiation luminosity with time and thus significant brightening of an early afterglow. Based on this model, we carry out numerical calculations and fit well early afterglows of 12 GRBs assuming sufficiently strong fallback accretion. If the accretion is very weak, our model turns out to be the conventional energy-injection scenario of a pulsar. Therefore, our model can provide a unified explanation for the shallow decay phase, plateaus, and significant brightening of early afterglows.

  2. Constraints on Neutron Star Parameters from Burst Oscillation Light Curves of the Accreting Millisecond Pulsar XTE J1814-338

    E-Print Network [OSTI]

    Sudip Bhattacharyya; Tod E. Strohmayer; M. Coleman Miller; Craig B. Markwardt

    2004-10-11T23:59:59.000Z

    Detailed modeling of the millisecond brightness oscillations during thermonuclear bursts from low mass X-ray binaries can provide important information about neutron star structure. Until now the implementation of this idea has not been entirely successful, largely because of the negligible harmonic content in burst oscillation lightcurves. However, the recent discovery of non-sinusoidal burst oscillation lightcurves from the accreting millisecond pulsar XTE J1814-338 has changed this situation. We, therefore, for the first time, make use of this opportunity to constrain neutron star parameters. In our detailed study of the lightcurves of 22 bursts, we fit the burst oscillation lightcurves with fully general relativistic models that include light-bending and frame-dragging for lightcurve calculation, and compute numerically the structure of neutron stars using realistic equations of state. We find that for our model and parameter grid values, at the 90% confidence level, Rc^2/GM > 4.2 for the neutron star in XTE J1814-338. We also find that the photons from the thermonuclear flash come out through the layers of accreted matter under conditions consistent with Thomson scattering, and show that the secondary companion is a hydrogen burning main sequence star, with possible bloating (probably due to X-ray heating).

  3. Millisecond dip events in the 2007 RXTE/PCA data of Sco X-1 and the TNO size distribution

    E-Print Network [OSTI]

    Liu, Chih-Yuan; Liang, Jau-Shian; King, Sun-Kun

    2008-01-01T23:59:59.000Z

    Millisecond dips in the RXTE/PCA archival data of Sco X-1 taken from 1996 to 2002 were reported recently. Those dips were found to be most likely caused by instrumental dead time but may also contain some true astronomical events, which were interpreted as the occultation of X-rays from Sco X-1 by Trans-Neptunian Objects (TNO) of 100-m size. Here we report the results of search for millisecond dip events with the new RXTE/PCA data of Sco X-1 taken in year 2007. Adopting the same selection criteria as that in the previous study, we found only 3 dip events in 72-ks data, much fewer than the 107 events found in the 560-ks data taken from 1996 to 2002 reported earlier. The new data provides more detailed information of individual `very large events' (VLEs), which is not available in the old archival data. Although the number of VLEs does not obviously increase during the occurrence of dip events, all the 3 dip events are coincident in time with VLEs that have no flags set for any of the propane or the 6 main xeno...

  4. Fast Proton Decay

    E-Print Network [OSTI]

    Tianjun Li; Dimitri V. Nanopoulos; Joel W. Walker

    2010-09-10T23:59:59.000Z

    We consider proton decay in the testable flipped SU(5) X U(1)_X models with TeV-scale vector-like particles which can be realized in free fermionic string constructions and F-theory model building. We significantly improve upon the determination of light threshold effects from prior studies, and perform a fresh calculation of the second loop for the process p \\to e^+ \\pi^0 from the heavy gauge boson exchange. The cumulative result is comparatively fast proton decay, with a majority of the most plausible parameter space within reach of the future Hyper-Kamiokande and DUSEL experiments. Because the TeV-scale vector-like particles can be produced at the LHC, we predict a strong correlation between the most exciting particle physics experiments of the coming decade.

  5. Smashing Protons to Smithereens

    ScienceCinema (OSTI)

    Marc-André Pleier

    2010-09-01T23:59:59.000Z

    Pleier discusses the extraordinary research taking place at the Large Hadron Collider (LHC) ? the world?s newest, biggest, and highest energy particle accelerator located at CERN. Pleier is one of hundreds of researchers from around the world working on ATLAS, a seven-story particle detector positioned at a point where the LHC?s oppositely circulating beams of protons slam into one another head-on.

  6. On the Nature of Pulsar Radio Emission

    E-Print Network [OSTI]

    Lyutikov, M; Machabeli, G Z; Lyutikov, Maxim; Blandford, Roger D.; Machabeli, George

    1998-01-01T23:59:59.000Z

    A theory of pulsar radio emission generation, in which the observed waves are produced directly by maser-type plasma instabilities operating at the anomalous cyclotron-Cherenkov resonance $\\omega- k_{\\parallel} v_{\\parallel} + \\omega_B/ v_{\\parallel} - k_{\\perp} u_d =0$, is capable of explaining the main observational characteristics of pulsar radio emission. The instabilities are due to the interaction of the fast particles from the primary beam and the tail of the distribution with the normal modes of a strongly magnetized one-dimensional electron-positron plasma. The waves emitted at these resonances are vacuum-like, electromagnetic waves that may leave the magnetosphere directly. In this model, the cyclotron-Cherenkov instability is responsible for core emission pattern and the Cherenkov-drift instability produces conal emission. The conditions for the development of the cyclotron-Cherenkov instability are satisfied for both typical and millisecond pulsars provided that the streaming energy of the bulk pl...

  7. Two Emission Mechanisms in the Fermi Bubbles: A Possible Signal of Annihilating Dark Matter

    SciTech Connect (OSTI)

    Hooper, Dan; Slatyer, Tracy R.

    2013-09-01T23:59:59.000Z

    We study the variation of the spectrum of the Fermi Bubbles with Galactic latitude. Far from the Galactic plane (|b| > 30 degrees), the observed gamma-ray emission is nearly invariant with latitude, and is consistent with arising from inverse Compton scattering of the interstellar radiation field by cosmic-ray electrons with an approximately power-law spectrum. The same electrons in the presence of microgauss-scale magnetic fields can also generate the the observed microwave "haze". At lower latitudes (b < 20 degrees), in contrast, the spectrum of the emission correlated with the Bubbles possesses a pronounced spectral feature peaking at 1-4 GeV (in E^2 dN/dE) which cannot be generated by any realistic spectrum of electrons. Instead, we conclude that a second (non-inverse-Compton) emission mechanism must be responsible for the bulk of the low-energy, low-latitude emission. This second component is spectrally similar to the excess GeV emission previously reported from the Galactic Center (GC), and also appears spatially consistent with a luminosity per volume falling approximately as r^-2.4, where r is the distance from the GC. We argue that the spectral feature visible in the low-latitude Bubbles is the extended counterpart of the GC excess, now detected out to at least 2-3 kpc from the GC. The spectrum and angular distribution of the signal is consistent with that predicted from ~10 GeV dark matter particles annihilating to leptons, or from ~50 GeV dark matter particles annihilating to quarks, following a distribution similar to the canonical Navarro-Frenk-White (NFW) profile. We also consider millisecond pulsars as a possible astrophysical explanation for the signal, as observed millisecond pulsars possess a spectral cutoff at approximately the required energy. Any such scenario would require a large population of unresolved millisecond pulsars extending at least 2-3 kpc from the GC.

  8. Beta-Delayed Two-Particle Emission

    SciTech Connect (OSTI)

    Borge, M.J.G.

    2000-12-31T23:59:59.000Z

    A panorama of beta-delayed nuclear decay is sketched. Beginning with beta-delayed two-neutron emission, the author moves on to beta-delayed two-proton emission and beta-delayed multiparticle emission. After touching briefly on the theoretical approach to understanding these phenomena, he reports on two experiments done at ISOLDE (CERN) on the decay of {sup 31}Ar with the goal of studying the mechanisms of {beta}-delayed two proton emission. This example shows the potentiality of the new technology that allows design setups with high efficiency for multiparticle detection. In combination with high-purity sources and the use of low-energy beams to produce point-like sources, information at the drip line can be extracted that is of comparable quality to that obtained near stability.

  9. Millisecond dip events in the 2007 RXTE/PCA data of Sco X-1 and the TNO size distribution

    E-Print Network [OSTI]

    Chih-Yuan Liu; Hsiang-Kuang Chang; Jau-Shian Liang; Sun-Kun King

    2008-05-12T23:59:59.000Z

    Millisecond dips in the RXTE/PCA archival data of Sco X-1 taken from 1996 to 2002 were reported recently. Those dips were found to be most likely caused by instrumental dead time but may also contain some true astronomical events, which were interpreted as the occultation of X-rays from Sco X-1 by Trans-Neptunian Objects (TNO) of 100-m size. Here we report the results of search for millisecond dip events with the new RXTE/PCA data of Sco X-1 taken in year 2007. Adopting the same selection criteria as that in the previous study, we found only 3 dip events in 72-ks data, much fewer than the 107 events found in the 560-ks data taken from 1996 to 2002 reported earlier. The new data provides more detailed information of individual `very large events' (VLEs), which is not available in the old archival data. Although the number of VLEs does not obviously increase during the occurrence of dip events, all the 3 dip events are coincident in time with VLEs that have no flags set for any of the propane or the 6 main xenon anodes. It is a strong indication of instrumental effects. No significant dips which might be real occultation by 60 -- 100 m TNOs were observed. With only 72-ks data, however, the previously proposed possibility that about 10 percent of the dip events might not be instrumental still cannot be strictly excluded. Using the absence of those anomalous VLEs as the criterion for identifying non-instrumental dip events, we found, at a lower confidence level, 4 dip events of duration 8 - 10 ms in the 72-ks data. Upper limits to the size distribution of TNOs at the small size end are suggested.

  10. Cataractogenic effects of proton radiation

    E-Print Network [OSTI]

    Kyzar, James Ronald

    1972-01-01T23:59:59.000Z

    vulnerable organs, created an urgent need for investigation of proton radiation cataracto- genesis. In a statistical analysis of collected data on solar proton events taking into consideration possible shield- ing and mission duration, an investigator... energy group to a high of 74 for the 20 Mev proton energy group. As previously stated, the maximum possible numerical value was 400. The mean values for degree of lens opacities for the controls and the five dosage subgroups within the 10 Mev, 20 Mev...

  11. Proton Resonance Spectroscopy

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible forPortsmouth/Paducah47,193.70 HgPromisingProtectingSciTechProton Dripping Tests

  12. PROTON BEAM REQUIREMENTS FOR A NEUTRINO FACTORY AND MUON COLLIDER

    E-Print Network [OSTI]

    Zisman, Michael S.

    2010-01-01T23:59:59.000Z

    Table 1 summarizes the NF proton driver parameters obtainedboth facilities. Table 1. Proton driver requirements for arepetition frequency (Hz) Proton energy (GeV) Proton rms

  13. Proton slip in the ATP synthase of Rhodobacter capsulatus: induction, proton conduction, and nucleotide dependence

    E-Print Network [OSTI]

    Steinhoff, Heinz-Jürgen

    Proton slip in the ATP synthase of Rhodobacter capsulatus: induction, proton conduction. Uncoupled proton leakage (slip) has only been observed in chloroplast enzyme at unphysiologically low nucleotide concentration. We investigated the properties of proton slip in chromatophores (sub

  14. Measurement of asymmetric component in proton-proton collisions

    E-Print Network [OSTI]

    Adam Bzdak

    2009-04-06T23:59:59.000Z

    It is argued that a standard measurement of multiplicities in proton-proton collisions is sufficient to construct a single nucleon fragmentation function. A proposed method is based on measurement of mean values of produced particles and pairs of particles in symmetric and asymmetric bins

  15. Elastic proton-proton and proton-antiproton scattering: analysis of complete set of helicity amplitudes

    E-Print Network [OSTI]

    V. A. Okorokov; S. B. Nurushev

    2007-11-14T23:59:59.000Z

    The differential cross-sections are calculated for proton-proton and proton-antiproton elastic scattering using the phenomenological model based on the analytic parameterizations for global scattering parameters (total cross-section and $\\rho$ - parameter), crossing symmetry and derivative relations. We confront our model predictions with experimental data in wide range of energy and momentum transfer. The suggested method may be useful for PAX Program (GSI) as well as for high-energy experiments at RHIC and LHC.

  16. On the Nature of Pulsar Radio Emission

    E-Print Network [OSTI]

    Maxim Lyutikov; Roger D. Blandford; George Machabeli

    1998-06-27T23:59:59.000Z

    A theory of pulsar radio emission generation, in which the observed waves are produced directly by maser-type plasma instabilities operating at the anomalous cyclotron-Cherenkov resonance $\\omega- k_{\\parallel} v_{\\parallel} + \\omega_B/ \\gamma_{res}=0$ and the Cherenkov-drift resonance $\\omega- k_{\\parallel} v_{\\parallel} - k_{\\perp} u_d =0$, is capable of explaining the main observational characteristics of pulsar radio emission. The instabilities are due to the interaction of the fast particles from the primary beam and the tail of the distribution with the normal modes of a strongly magnetized one-dimensional electron-positron plasma. The waves emitted at these resonances are vacuum-like, electromagnetic waves that may leave the magnetosphere directly. In this model, the cyclotron-Cherenkov instability is responsible for core emission pattern and the Cherenkov-drift instability produces conal emission. The conditions for the development of the cyclotron-Cherenkov instability are satisfied for both typical and millisecond pulsars provided that the streaming energy of the bulk plasma is not very high $\\gamma_p \\approx 10$. In a typical pulsar the cyclotron-Cherenkov and Cherenkov-drift resonances occur in the outer parts of magnetosphere at $r_{res} \\approx 10^9 cm$. This theory can account for various aspects of pulsar phenomenology including the morphology of the pulses, their polarization properties and their spectral behavior. We propose several observational tests for the theory. The most prominent prediction are the high altitudes of the emission region and the linear polarization of conal emission in the plane orthogonal to the local osculating plane of the magnetic field.

  17. Treatment of the proton-proton Coulomb force in proton-deuteron breakup Faddeev calculations

    E-Print Network [OSTI]

    H. Witala; R. Skibinski; J. Golak; W. Glockle

    2009-06-17T23:59:59.000Z

    We extend our approach to incorporate the proton-proton (pp) Coulomb force into the three-nucleon (3N) Faddeev calculations from elastic proton-deuteron (pd) scattering to the breakup process. The main new ingredient is a 3-dimensional screened pp Coulomb t-matrix obtained by a numerical solution of the 3-dimensional Lippmann-Schwinger equation. We demonstrate numerically that the proton-deuteron breakup observables can be determined from the resulting on-shell 3N amplitudes increasing the screening radius. However, contrary to the pd elastic scattering, the screening limit exists only after renormalisation of the pp t-matrices.

  18. Proton-proton correlations observed in two-proton decay of $^{19}$Mg and $^{16}$Ne

    E-Print Network [OSTI]

    I. Mukha; L. Grigorenko; K. Summerer; L. Acosta; M. A. G. Alvarez; E. Casarejos; A. Chatillon; D. Cortina-Gil; J. Espino; A. Fomichev; J. E. Garcia-Ramos; H. Geissel; J. Gomez-Camacho; J. Hofmann; O. Kiselev; A. Korsheninnikov; N. Kurz; Yu. Litvinov; I. Martel; C. Nociforo; W. Ott; M. Pfutzner; C. Rodriguez-Tajes; E. Roeckl; M. Stanoiu; H. Weick; P. J. Woods

    2008-02-28T23:59:59.000Z

    Proton-proton correlations were observed for the two-proton decays of the ground states of $^{19}$Mg and $^{16}$Ne. The trajectories of the respective decay products, $^{17}$Ne+p+p and $^{14}$O+p+p, were measured by using a tracking technique with microstrip detectors. These data were used to reconstruct the angular correlations of fragments projected on planes transverse to the precursor momenta. The measured three-particle correlations reflect a genuine three-body decay mechanism and allowed us to obtain spectroscopic information on the precursors with valence protons in the $sd$ shell.

  19. Delivering High IntensityDelivering High Intensity Proton Beam:Proton Beam

    E-Print Network [OSTI]

    McDonald, Kirk

    11 Delivering High IntensityDelivering High Intensity Proton Beam:Proton Beam: Lessons for the NextFACT08NuFACT08 ­­ 4 July4 July S. ChildressS. Childress ­­ Proton BeamsProton Beams 22 Presentation OutlinePresentation Outline Key Proton Beam ConsiderationsKey Proton Beam Considerations The First

  20. Proton Decay and the Planck Scale

    E-Print Network [OSTI]

    Larson, Daniel T.

    2009-01-01T23:59:59.000Z

    LBNL- 56556 PROTON DECAY AND THE PLANCK SCALE DANIEL T.ph/0410035v1 2 Oct 2004 PROTON DECAY AND THE PLANCK SCALE ?without grand uni?cation, proton decay can be a powerful

  1. PRESSURE OF THE PROTON PLASMA IN THE INNER HELIOSHEATH

    SciTech Connect (OSTI)

    Livadiotis, G.; McComas, D. J.; Schwadron, N. A.; Fuselier, S. A. [Southwest Research Institute, San Antonio, TX (United States)] [Southwest Research Institute, San Antonio, TX (United States); Funsten, H. O., E-mail: glivadiotis@swri.edu [Los Alamos National Laboratory, Los Alamos, NM (United States)

    2013-01-10T23:59:59.000Z

    We develop a physical model to study the pressure of the source proton plasma in the inner heliosheath based on the IBEX Energetic Neutral Atom (ENA) spectra. A multiple linear regression technique is used to parameterize the proton distribution function, by connecting the observed ENA flux spectrum from IBEX-Hi with the power-law of the model proton distribution. We calculate the partial pressure over the measured energy range, using (1) a non-parametric method by integrating the observed ENA flux, and (2) a parametric method by integrating the modeled distribution of protons in the inner heliosheath. The two sky maps of the parametric and non-parametric partial pressures are nearly identical, owing to their power-law distributions at high energies; the kappa distribution is such a function that can be reduced to a power-law in the IBEX-Hi energy range. The slight differences between the two partial pressures may indicate protons that are not described by the kappa distribution, and instead, involve newer or 'immature' (spherical shell) pick-up proton distributions. Ultimately, however, these become incorporated with the solar wind into one single proton population described by a kappa distribution. Moreover, we derive analytically (1) the ENA flux spectra, which suggests that this flux maximizes at {approx}30 eV, and (2) the differential pressure, which provides estimates of the partial pressures outside of those measured by IBEX-Hi. Under the assumptions of the modeled ENA spectra, the Ribbon emissions appear to be primarily limited to the energy ranges of IBEX-Lo and IBEX-Hi.

  2. Advanced Materials for Proton Exchange Membranes | Department...

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

    Advanced Materials for Proton Exchange Membranes Advanced Materials for Proton Exchange Membranes A presentation to the High Temperature Membranes Working Group meeting, May 19,...

  3. Pion mass effects on axion emission from neutron stars through NN bremsstrahlung processes

    E-Print Network [OSTI]

    S. Stoica; B. Pastrav; J. E. Horvath; M. P. Allen

    2009-11-30T23:59:59.000Z

    The rates of axion emission by nucleon-nucleon bremsstrahlung are calculated with the inclusion of the full momentum contribution from a nuclear one pion exchange (OPE) potential. The contributions of the neutron-neutron (nn), proton-proton (pp) and neutron-proton (np) processes in both the nondegenerate and degenerate limits are explicitly given. We find that the finite momentum corrections to the emissivities are quantitatively significant for the non-degenerate regime and temperature-dependent, and should affect the existing axion mass bounds. The trend of these nuclear effects is to diminish the emissivities.

  4. Proton and Neutrino Extragalactic Astronomy

    E-Print Network [OSTI]

    Paolo Lipari

    2008-08-04T23:59:59.000Z

    The study of extragalactic sources of high energy radiation via the direct measurement of the proton and neutrino fluxes that they are likely to emit is one of the main goals for the future observations of the recently developed air showers detectors and neutrino telescopes. In this work we discuss the relation between the inclusive proton and neutrino signals from the ensemble of all sources in the universe, and the resolved signals from the closest and brightest objects. We also compare the sensitivities of proton and neutrino telescopes and comment on the relation between these two new astronomies.

  5. The Connection Between Low-Mass X-ray Binaries and (Millisecond) Pulsars: A Binary Evolution Perspective

    E-Print Network [OSTI]

    Christopher J. Deloye

    2007-10-01T23:59:59.000Z

    I review the evolutionary connection between low-mass X-ray binaries (LMXBs) and pulsars with binary companions (bPSRs) from a stellar binary evolution perspective. I focus on the evolution of stellar binaries with end-states consisting of a pulsar with a low-mass (<1.0 solar mass) companion, starting at the point the companion's progenitor first initiates mass transfer onto the neutron star. Whether this mass transfer is stable and the physics driving ongoing mass transfer partitions the phase space of the companions's initial mass and initial orbital period into five regions. The qualitative nature of the mass-transfer process and the binary's final end-state differ between systems in each region; four of these regions each produce a particular class of LMXBs. I compare the theoretical expectations to the populations of galactic field LMXBs with companion-mass constraints and field bPSRs. I show that the population of accreting millisecond pulsars are all identified with only two of the four LMXB classes and that these systems do not have readily identifiable progeny in the bPSR population. I discuss which sub-populations of bPSRs can be explained by binary evolution theory and those that currently are not. Finally I discuss some outstanding questions in this field.

  6. ACCELERATED ORBITAL EXPANSION AND SECULAR SPIN-DOWN OF THE ACCRETING MILLISECOND PULSAR SAX J1808.4-3658

    SciTech Connect (OSTI)

    Patruno, Alessandro; Bult, Peter; Wijnands, Rudy; Van der Klis, Michiel [Astronomical Institute 'Anton Pannekoek', University of Amsterdam, Science Park 904, 1098 XH Amsterdam (Netherlands); Gopakumar, Achamveedu [Department of Astronomy and Astrophysics, Tata Institute of Fundamental Research, Colaba, Mumbai 400005 (India); Hartman, Jacob M. [Jet Propulsion Laboratory, Pasadena, CA 91109 (United States); Chakrabarty, Deepto [Department of Physics and Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States)

    2012-02-20T23:59:59.000Z

    The accreting millisecond pulsar SAX J1808.4-3658 has shown a peculiar orbital evolution in the past with an orbital expansion much faster than expected from standard binary evolutionary scenarios. Previous limits on the pulsar spin frequency derivative during transient accretion outbursts were smaller than predicted by standard magnetic accretion torque theory, while the spin evolution between outbursts was consistent with magnetic dipole spin-down. In this Letter, we present the results of a coherent timing analysis of the 2011 outburst observed by the Rossi X-Ray Timing Explorer and extend our previous long-term measurements of the orbital and spin evolution over a baseline of 13 years. We find that the expansion of the 2 hr orbit is accelerating at a rate of P-double dot{sub b} approx. = 1.6 x 10{sup -20} s s{sup -2} and we interpret this as the effect of short-term angular momentum exchange between the mass donor and the orbit. The gravitational quadrupole coupling due to variations in the oblateness of the companion can be a viable mechanism for explaining the observations. No significant spin frequency derivatives are detected during the 2011 outburst (|{nu}-dot| < or approx. 4 x 10{sup -13} Hz s{sup -1}) and the long-term spin-down remains stable over 13 years with {nu}-dot approx. = -10{sup -15} Hz s{sup -1}.

  7. Proton-Coupled Electron Transfer

    SciTech Connect (OSTI)

    Weinberg, Dave; Gagliardi, Christopher J.; Hull, Jonathan F; Murphy, Christine Fecenko; Kent, Caleb A.; Westlake, Brittany C.; Paul, Amit; Ess, Daniel H; McCafferty, Dewey Granville; Meyer, Thomas J

    2012-01-01T23:59:59.000Z

    Proton-Coupled Electron Transfer (PCET) describes reactions in which there is a change in both electron and proton content between reactants and products. It originates from the influence of changes in electron content on acid?base properties and provides a molecular-level basis for energy transduction between proton transfer and electron transfer. Coupled electron?proton transfer or EPT is defined as an elementary step in which electrons and protons transfer from different orbitals on the donor to different orbitals on the acceptor. There is (usually) a clear distinction between EPT and H-atom transfer (HAT) or hydride transfer, in which the transferring electrons and proton come from the same bond. Hybrid mechanisms exist in which the elementary steps are different for the reaction partners. EPT pathways such as PhO•/PhOH exchange have much in common with HAT pathways in that electronic coupling is significant, comparable to the reorganization energy with H{sub DA} ~ ?. Multiple-Site Electron?Proton Transfer (MS-EPT) is an elementary step in which an electron?proton donor transfers electrons and protons to different acceptors, or an electron?proton acceptor accepts electrons and protons from different donors. It exploits the long-range nature of electron transfer while providing for the short-range nature of proton transfer. A variety of EPT pathways exist, creating a taxonomy based on what is transferred, e.g., 1e{sup -}/2H{sup +} MS-EPT. PCET achieves “redox potential leveling” between sequential couples and the buildup of multiple redox equivalents, which is of importance in multielectron catalysis. There are many examples of PCET and pH-dependent redox behavior in metal complexes, in organic and biological molecules, in excited states, and on surfaces. Changes in pH can be used to induce electron transfer through films and over long distances in molecules. Changes in pH, induced by local electron transfer, create pH gradients and a driving force for long-range proton transfer in Photosysem II and through other biological membranes. In EPT, simultaneous transfer of electrons and protons occurs on time scales short compared to the periods of coupled vibrations and solvent modes. A theory for EPT has been developed which rationalizes rate constants and activation barriers, includes temperature- and driving force (?G)-dependences implicitly, and explains kinetic isotope effects. The distance-dependence of EPT is dominated by the short-range nature of proton transfer, with electron transfer being far less demanding.Changes in external pH do not affect an EPT elementary step. Solvent molecules or buffer components can act as proton donor acceptors, but individual H2O molecules are neither good bases (pK{sub a}(H{sub 3}O{sup +}) = ?1.74) nor good acids (pK{sub a}(H{sub 2}O) = 15.7). There are many examples of mechanisms in chemistry, in biology, on surfaces, and in the gas phase which utilize EPT. PCET and EPT play critical roles in the oxygen evolving complex (OEC) of Photosystem II and other biological reactions by decreasing driving force and avoiding high-energy intermediates.

  8. Parametric Model for Astrophysical Proton-Proton Interactions and Applications

    SciTech Connect (OSTI)

    Karlsson, Niklas; /Royal Inst. Tech., Stockholm; ,

    2008-01-29T23:59:59.000Z

    Observations of gamma-rays have been made from celestial sources such as active galaxies, gamma-ray bursts and supernova remnants as well as the Galactic ridge. The study of gamma rays can provide information about production mechanisms and cosmic-ray acceleration. In the high-energy regime, one of the dominant mechanisms for gamma-ray production is the decay of neutral pions produced in interactions of ultra-relativistic cosmic-ray nuclei and interstellar matter. Presented here is a parametric model for calculations of inclusive cross sections and transverse momentum distributions for secondary particles--gamma rays, e{sup {+-}}, {nu}{sub e}, {bar {nu}}{sub e}, {nu}{sub {mu}} and {bar {nu}}{sub {mu}}--produced in proton-proton interactions. This parametric model is derived on the proton-proton interaction model proposed by Kamae et al.; it includes the diffraction dissociation process, Feynman-scaling violation and the logarithmically rising inelastic proton-proton cross section. To improve fidelity to experimental data for lower energies, two baryon resonance excitation processes were added; one representing the {Delta}(1232) and the other multiple resonances with masses around 1600 MeV/c{sup 2}. The model predicts the power-law spectral index for all secondary particle to be about 0.05 lower in absolute value than that of the incident proton and their inclusive cross sections to be larger than those predicted by previous models based on the Feynman-scaling hypothesis. The applications of the presented model in astrophysics are plentiful. It has been implemented into the Galprop code to calculate the contribution due to pion decays in the Galactic plane. The model has also been used to estimate the cosmic-ray flux in the Large Magellanic Cloud based on HI, CO and gamma-ray observations. The transverse momentum distributions enable calculations when the proton distribution is anisotropic. It is shown that the gamma-ray spectrum and flux due to a pencil beam of protons varies drastically with viewing angle. A fanned proton jet with a Gaussian intensity profile impinging on surrounding material is given as a more realistic example. As the observer is moved off the jet axis, the peak of the spectrum is moved to lower energies.

  9. High resolution Cerenkov light imaging of induced positron distribution in proton therapy

    SciTech Connect (OSTI)

    Yamamoto, Seiichi, E-mail: s-yama@met.nagoya-u.ac.jp; Fujii, Kento; Morishita, Yuki; Okumura, Satoshi; Komori, Masataka [Radiological and Medical Laboratory Sciences, Nagoya University Graduate School of Medicine, Aichi 461-8673 (Japan); Toshito, Toshiyuki [Department of Proton Therapy Physics, Nagoya Proton Therapy Center, Nagoya City West Medical Center, Aichi 462-8508 (Japan)

    2014-11-01T23:59:59.000Z

    Purpose: In proton therapy, imaging of the positron distribution produced by fragmentation during or soon after proton irradiation is a useful method to monitor the proton range. Although positron emission tomography (PET) is typically used for this imaging, its spatial resolution is limited. Cerenkov light imaging is a new molecular imaging technology that detects the visible photons that are produced from high-speed electrons using a high sensitivity optical camera. Because its inherent spatial resolution is much higher than PET, the authors can measure more precise information of the proton-induced positron distribution with Cerenkov light imaging technology. For this purpose, they conducted Cerenkov light imaging of induced positron distribution in proton therapy. Methods: First, the authors evaluated the spatial resolution of our Cerenkov light imaging system with a {sup 22}Na point source for the actual imaging setup. Then the transparent acrylic phantoms (100 × 100 × 100 mm{sup 3}) were irradiated with two different proton energies using a spot scanning proton therapy system. Cerenkov light imaging of each phantom was conducted using a high sensitivity electron multiplied charge coupled device (EM-CCD) camera. Results: The Cerenkov light’s spatial resolution for the setup was 0.76 ± 0.6 mm FWHM. They obtained high resolution Cerenkov light images of the positron distributions in the phantoms for two different proton energies and made fused images of the reference images and the Cerenkov light images. The depths of the positron distribution in the phantoms from the Cerenkov light images were almost identical to the simulation results. The decay curves derived from the region-of-interests (ROIs) set on the Cerenkov light images revealed that Cerenkov light images can be used for estimating the half-life of the radionuclide components of positrons. Conclusions: High resolution Cerenkov light imaging of proton-induced positron distribution was possible. The authors conclude that Cerenkov light imaging of proton-induced positron is promising for proton therapy.

  10. Proton Solvation and Proton Mobility Department of Physical Chemistry and the Fritz Haber Research Center,

    E-Print Network [OSTI]

    Agmon, Noam

    Proton Solvation and Proton Mobility NOAM AGMON Department of Physical Chemistry and the Fritz for proton solvation and proton mobility is analyzed and the results are compared with recent simulations. Three factors con­ tribute to differences in proton solvation energies: hydrogen­bond cleavage, changes

  11. A test of the millisecond magnetar central engine model of gamma-ray bursts with swift data

    SciTech Connect (OSTI)

    Lü, Hou-Jun; Zhang, Bing, E-mail: lhj@physics.unlv.edu, E-mail: zhang@physics.unlv.edu [Department of Physics and Astronomy, University of Nevada Las Vegas, Las Vegas, NV 89154 (United States)

    2014-04-10T23:59:59.000Z

    A rapidly spinning, strongly magnetized neutron star (magnetar) has been proposed as one possible candidate of the central engine of gamma-ray bursts (GRBs). We systematically analyze the Swift/XRT light curves of long GRBs detected before 2013 August, and characterize them into four categories based on how likely they may harbor a magnetar central engine: Gold, Silver, Aluminum, and Non-magnetar. We also independently analyze the data of short GRBs with a putative magnetar central engine. We then perform a statistical study of various properties of the magnetar samples and the non-magnetar sample, and investigate whether the data are consistent with the hypothesis that there exist two types of central engines. By deriving the physical parameters of the putative magnetars, we find that the observations of the Gold and Silver samples are generally consistent with the predictions of the magnetar model. For a reasonable beaming factor for long GRBs, the derived magnetar surface magnetic field B{sub p} and initial spin period P {sub 0} fall into the reasonable range. Magnetar winds in short GRBs, on the other hand, are consistent with being isotropic. No GRB in the magnetar sample has a beam-corrected total energy exceeding the maximum energy budget defined by the initial spin energy of the magnetar, while some non-magnetar GRBs do violate such a limit. With beaming correction, on average the non-magnetar sample is more energetic and luminous than the magnetar samples. Our analysis hints that millisecond magnetars are likely operating in a good fraction, but probably not all, GRBs.

  12. Proton-proton Scattering Above 3 GeV/c

    SciTech Connect (OSTI)

    A. Sibirtsev, J. Haidenbauer, H.-W. Hammer S. Krewald ,Ulf-G. Meissner

    2010-01-01T23:59:59.000Z

    A large set of data on proton-proton differential cross sections, analyzing powers and the double-polarization parameter A{sub NN} is analyzed employing the Regge formalism. We find that the data available at proton beam momenta from 3 GeV/c to 50 GeV/c exhibit features that are very well in line with the general characteristics of Regge phenomenology and can be described with a model that includes the {rho}, {omega}, f{sub 2}, and a{sub 2} trajectories and single-Pomeron exchange. Additional data, specifically for spin-dependent observables at forward angles, would be very helpful for testing and refining our Regge model.

  13. Measurement of the Wolfenstein parameters for proton-proton and proton-neutron scattering at 500 MeV

    SciTech Connect (OSTI)

    Marshall, J.A.

    1984-07-01T23:59:59.000Z

    Using liquid hydrogen and liquid deuterium targets respectively, forward angle (ten degrees to sixty degrees in the center of Mass) free proton-proton and quasielastic proton-proton and proton-neutron triple scattering data at 500 MeV have been obtained using the high resolution spectrometer at the Los Alamos Meson Physics Facility. The data are in reasonable agreement with recent predictions from phase shift analyses, indicating that the proton-nucleon scattering amplitudes are fairly well determined at 500 MeV. 32 references.

  14. Proton irradiation effect on SCDs

    E-Print Network [OSTI]

    Yan-Ji Yang; Jing-Bin Lu; Yu-Sa Wang; Yong Chen; Yu-Peng Xu; Wei-Wei Cui; Wei Li; Zheng-Wei Li; Mao-Shun Li; Xiao-Yan Liu; Juan Wang; Da-Wei Han; Tian-Xiang Chen; Cheng-Kui Li; Jia Huo; Wei Hu; Yi Zhang; Bo Lu; Yue Zhu; Ke-Yan Ma; Di Wu; Yan Liu; Zi-Liang Zhang; Guo-He Yin; Yu Wang

    2014-04-19T23:59:59.000Z

    The Low Energy X-ray Telescope is a main payload on the Hard X-ray Modulation Telescope satellite. The swept charge device is selected for the Low Energy X-ray Telescope. As swept charge devices are sensitive to proton irradiation, irradiation test was carried out on the HI-13 accelerator at the China Institute of Atomic Energy. The beam energy was measured to be 10 MeV at the SCD. The proton fluence delivered to the SCD was $3\\times10^{8}\\mathrm{protons}/\\mathrm{cm}^{2}$ over two hours. It is concluded that the proton irradiation affects both the dark current and the charge transfer inefficiency of the SCD through comparing the performance both before and after the irradiation. The energy resolution of the proton-irradiated SCD is 212 eV@5.9 keV at $-60\\,^{\\circ}\\mathrm{C}$, while it before irradiated is 134 eV. Moreover, better performance can be reached by lowering the operating temperature of the SCD on orbit.

  15. Proton-proton scattering without Coulomb force renormalization

    E-Print Network [OSTI]

    R. Skibinski; J. Golak; H. Witala; W. Glockle

    2009-03-06T23:59:59.000Z

    We demonstrate numerically that proton-proton (pp) scattering observables can be determined directly by standard short range methods using a screened pp Coulomb force without renormalization. In examples the appropriate screening radii are given. We also numerically investigate solutions of the 3-dimensional Lippmann-Schwinger (LS) equation for a screened Coulomb potential alone in the limit of large screening radii and confirm analytically predicted properties for off-shell, half-shell and on-shell Coulomb t-matrices. These 3-dimensional solutions will form a basis for a novel approach to include the pp Coulomb interaction into the 3N Faddeev framework.

  16. Proton-proton fusion in lattice effective field theory

    E-Print Network [OSTI]

    Gautam Rupak; Pranaam Ravi

    2014-11-10T23:59:59.000Z

    The proton-proton fusion rate is calculated at low energy in a lattice effective field theory (EFT) formulation. The strong and the Coulomb interactions are treated non-perturbatively at leading order in the EFT. The lattice results are shown to accurately describe the low energy cross section within the validity of the theory at energies relevant to solar physics. In prior work in the literature, Coulomb effects were generally not included in non-perturbative lattice calculations. Work presented here is of general interest in nuclear lattice EFT calculations that involve Coulomb effects at low energy. It complements recent developments of the adiabatic projection method for lattice calculations of nuclear reactions.

  17. PROTON INDUCED SWELLING IN TYPE 316 STAINLESS STEEL

    E-Print Network [OSTI]

    Srivastava, A.K.

    2010-01-01T23:59:59.000Z

    McDonald, Void Formation in Proton- and Nicke1- Irradiatedowned rights. o -iii- PROTON INDUCED SWELLING IN TYPE 316I. II. Introduction Proton Damage Processes A. B.

  18. Proton Mass Shift in Muonic Hydrogen Atom

    E-Print Network [OSTI]

    Aiichi Iwazaki

    2014-08-11T23:59:59.000Z

    We show that the value of the proton mass depends on each bound state of muonic or electronic hydrogen atom. The charged particle bound to the proton produces magnetic field inside the proton. This makes a change to the amount of chiral condensate inside the proton. The change gives rise to the shift in the value of the proton mass. Numerically, the shift in the $2S$ state of the muonic hydrogen atom can be of the order of $0.1$ meV. The effect may solve the puzzle of the proton radius.

  19. Long-range azimuthal correlations in proton-proton and proton-nucleus collisions from the incoherent scattering of partons

    E-Print Network [OSTI]

    Guo-Liang Ma; Adam Bzdak

    2014-11-13T23:59:59.000Z

    We show that the incoherent elastic scattering of partons, as present in a multi-phase transport model (AMPT), with a modest parton-parton cross-section of $\\sigma=1.5 - 3$ mb, naturally explains the long-range two-particle azimuthal correlation as observed in proton-proton and proton-nucleus collisions at the Large Hadron Collider.

  20. Proton decay matrix elements from lattice QCD 

    E-Print Network [OSTI]

    Cooney, Paul

    2010-01-01T23:59:59.000Z

    We present results for the matrix elements relevant for proton decay in Grand Unified Theories (GUTs), using two methods. In the indirect method, we rely on an effective field theory description of proton decay, where ...

  1. Dynamics of low-energy antiproton annihilation in nuclei as inferred from inclusive proton and pion measurements

    SciTech Connect (OSTI)

    McGaughey, P.L.; Bol, K.D.; Clover, M.R.; DeVries, R.M.; DiGiacomo, N.J.; Kapustinsky, J.S.; Sondheim, W.E.; Smith, G.R.; Sunier, J.W.; Yariv, Y.

    1986-05-19T23:59:59.000Z

    The cross sections for the production of charged pions and protons from the annihilation of 608-MeV/c antiprotons on /sup 12/C, /sup 89/Y, and /sup 238/U are presented. The sources of pion and proton emission are inferrec from the rapidity distributions of the data. The results are compared to and seen to be in good agreement with intranuclear-cascade calculations.

  2. Transition in the Temperature-Dependence of GFP Fluorescence: From Proton Wires to Proton Exit

    E-Print Network [OSTI]

    Agmon, Noam

    Transition in the Temperature-Dependence of GFP Fluorescence: From Proton Wires to Proton Exit protein, photo-excitation leads to excited-state proton transfer from its chromophore, leaving behind a strongly fluorescing anion, while the proton is commonly thought to migrate internally to Glu-222. X

  3. Saving Fuel, Reducing Emissions

    E-Print Network [OSTI]

    Kammen, Daniel M.; Arons, Samuel M.; Lemoine, Derek M.; Hummel, Holmes

    2009-01-01T23:59:59.000Z

    lower greenhouse gas emissions from electricity productionAssessment of Greenhouse Gas Emissions from Plug-in Hybridof national greenhouse gas emissions. Both motor vehicle

  4. Proton++: A Customizable Declarative Multitouch Framework

    E-Print Network [OSTI]

    California at Irvine, University of

    Proton++: A Customizable Declarative Multitouch Framework Kenrick Kin1,2 Bj¨orn Hartmann1 Tony DeRose2 Maneesh Agrawala1 1 University of California, Berkeley 2 Pixar Animation Studios ABSTRACT Proton- sions of touch event symbols. It builds on the Proton frame- work by allowing developers to incorporate

  5. Proton Absorber Feasibility Study Chris Rogers,

    E-Print Network [OSTI]

    McDonald, Kirk

    Proton Absorber ­ Feasibility Study Chris Rogers, ASTeC, Rutherford Appleton Laboratory 14 Sept 2010 #12;Overview We have a problem with secondary protons in the front end Deposit significant Need remote handling (ouch) One way to fix this is using a proton absorber Change in beam power

  6. Photoproduction at HERA with a Leading Proton

    E-Print Network [OSTI]

    Photoproduction at HERA with a Leading Proton Hanna Mahlke­Kr¨uger H1 Collaboration, DESY Abstract. The total cross­section for the semi­inclusive photoproduction process with a leading proton in the final­sections refer to the kinematic range with transverse momenta of the scattered proton restricted to p T Ÿ 0:2 Ge

  7. Proton Hexality in Local Grand Unification

    E-Print Network [OSTI]

    Stefan Forste; Hans Peter Nilles; Saul Ramos-Sanchez; Patrick K. S. Vaudrevange

    2010-09-03T23:59:59.000Z

    Proton hexality is a discrete symmetry that avoids the problem of too fast proton decay in the supersymmetric extension of the standard model. Unfortunately it is inconsistent with conventional grand unification. We show that proton hexality can be incorporated in the scheme of "Local Grand Unification" discussed in the framework of model building in (heterotic) string theory.

  8. Studies of Charged Particle Emission in the Decay of 45Fe

    SciTech Connect (OSTI)

    Miernik, K. [University of Warsaw; Dominik, W. [University of Warsaw; Janas, Z. [University of Warsaw; Pfutzner, M. [University of Warsaw; Grigorenko, L. [Joint Institute for Nuclear Research, Dubna, Russia; Bingham, C. R. [University of Tennessee, Knoxville (UTK); Czyrkowski, H. [University of Warsaw; Cwiok, Mikolaj [Warsaw University; Darby, Iain [University of Tennessee, Knoxville (UTK); Dabrowski, Ryszard [Warsaw University; Ginter, T. N. [Michigan State University, East Lansing; Grzywacz, Robert [University of Tennessee, Knoxville (UTK); Karny, M. [University of Warsaw; Korgul, A. [University of Warsaw; Kusmierz, W. [University of Warsaw; Liddick, Sean [University of Tennessee, Knoxville (UTK); Rajabali, Mustafa [University of Tennessee, Knoxville (UTK); Rykaczewski, Krzysztof Piotr [ORNL; Stolz, A. [Michigan State University, East Lansing

    2008-01-01T23:59:59.000Z

    The decay of extremely neutron-deficient isotope 45Fe has been studied by using a new type of gaseous detector in which a technique of optical imaging is used to record tracks of charged particles. The two-proton radioactivity and the beta-decay channels accompanied by proton(s) emission were clearly identified. For the first time, the angular and energy correlations between two protons emitted from the 45Fe ground-state were measured. The obtained distributions were confronted with predictions of a three-body model. Studies of beta-decay channels of 45Fe provided first unambiguous evidence for the beta-delayed three proton emission.

  9. Soft Pion Emission in Hard Exclusive Pion Production

    E-Print Network [OSTI]

    Maxim V. Polyakov; Simone Stratmann

    2006-09-05T23:59:59.000Z

    We investigate hard exclusive reactions on the nucleon with soft pion emission. A parametrization of corresponding hadronic matrix elements in terms of parton distributions for final pion-nucleon state is provided. These distributions are calculated in terms of nucleon and pion GPDs and the pion distribution amplitude via soft-pion theorems. Some observables for the process of hard charged pion production on the proton with soft pion emission are computed.

  10. $\\Lambda$(1520)-Produktion in Proton-Proton- und zentralen Blei-Blei-Reaktionen bei 158 GeV pro Nukleon

    E-Print Network [OSTI]

    Markert, C

    2000-01-01T23:59:59.000Z

    $\\Lambda$(1520)-Produktion in Proton-Proton- und zentralen Blei-Blei-Reaktionen bei 158 GeV pro Nukleon

  11. Proton-Rich Nuclear Statistical Equilibrium

    E-Print Network [OSTI]

    I. R. Seitenzahl; F. X. Timmes; A. Marin-Laflèche; E. Brown; G. Magkotsios; J. Truran

    2008-08-14T23:59:59.000Z

    Proton-rich material in a state of nuclear statistical equilibrium (NSE) is one of the least studied regimes of nucleosynthesis. One reason for this is that after hydrogen burning, stellar evolution proceeds at conditions of equal number of neutrons and protons or at a slight degree of neutron-richness. Proton-rich nucleosynthesis in stars tends to occur only when hydrogen-rich material that accretes onto a white dwarf or neutron star explodes, or when neutrino interactions in the winds from a nascent proto-neutron star or collapsar-disk drive the matter proton-rich prior to or during the nucleosynthesis. In this paper we solve the NSE equations for a range of proton-rich thermodynamic conditions. We show that cold proton-rich NSE is qualitatively different from neutron-rich NSE. Instead of being dominated by the Fe-peak nuclei with the largest binding energy per nucleon that have a proton to nucleon ratio close to the prescribed electron fraction, NSE for proton-rich material near freeze-out temperature is mainly composed of Ni56 and free protons. Previous results of nuclear reaction network calculations rely on this non-intuitive high proton abundance, which this paper will explain. We show how the differences and especially the large fraction of free protons arises from the minimization of the free energy as a result of a delicate competition between the entropy and the nuclear binding energy.

  12. Polynomial fits and the proton radius puzzle

    E-Print Network [OSTI]

    E. Kraus; K. E. Mesick; A. White; R. Gilman; S. Strauch

    2014-10-27T23:59:59.000Z

    The Proton Radius Puzzle refers to the ~7{\\sigma} discrepancy that exists between the proton charge radius determined from muonic hydrogen and that determined from electronic hydrogen spectroscopy and electron-proton scattering. One possible partial resolution to the puzzle includes errors in the extraction of the proton radius from ep elastic scattering data. This possibility is made plausible by certain fits which extract a smaller proton radius from the scattering data consistent with that determined from muonic hydrogen. The reliability of some of these fits that yield a smaller proton radius was studied. We found that fits of form factor data with a truncated polynomial fit are unreliable and systematically give values for the proton radius that are too small. Additionally, a polynomial fit with a \\chi^2_{reduced} ~ 1 is not a sufficient indication for a reliable result.

  13. Stable transport in proton driven Fast Ignition

    E-Print Network [OSTI]

    Bret, A

    2009-01-01T23:59:59.000Z

    Proton beam transport in the context of proton driven Fast Ignition is usually assumed to be stable due to protons high inertia, but an analytical analysis of the process is still lacking. The stability of a charge and current neutralized proton beam passing through a plasma is therefore conducted here, for typical proton driven Fast Ignition parameters. In the cold regime, two fast growing Buneman-like modes are found, with an inverse growth-rate much smaller than the beam time-of-flight to the target core. The stability issue is thus not so obvious, and Kinetic effects are investigated. One unstable mode is found stabilized by the background plasma protons and electrons temperatures. The second mode is also damped, providing the proton beam thermal spread is larger than $\\sim$ 10 keV. In Fusion conditions, the beam propagation should therefore be stable.

  14. Saving Fuel, Reducing Emissions

    E-Print Network [OSTI]

    Kammen, Daniel M.; Arons, Samuel M.; Lemoine, Derek M.; Hummel, Holmes

    2009-01-01T23:59:59.000Z

    COMPACT EMISSIONS HEV PHEV marginal power plant is a coalpower uses relatively little coal, but in other cases emissions

  15. Transport-theoretic model for the electron-proton-hydrogen atom auroa. II. Model results

    SciTech Connect (OSTI)

    Strickland, D.J. [Computational Physics, Inc., Fairfax, VA (United States); Daniell, R.E. Jr. [Computational Physics, Inc., Newton, MA (United States); Basu, B. [Hanscom Air Force Base, MA (United States)] [and others

    1993-12-01T23:59:59.000Z

    In a companion paper, a self-consistent transport-theoretic model for the combined electron-proton-hydrogen atom aurora was described. In this paper, numberical results based on the model are presented. This is done for the pure electron aurora, the pure proton-hydrogen atom aurora, and finally for the combined aurora. Adopting commonly used types of energy distributions for the incident particle (electron and proton) fluxes, the authors give numerical solutions for the precipitating electron, proton, and hydrogen atom differential number fluxes. Results are also given for ionization yields and emission yields of the following features: N{sub 2}{sup +} first negative group (3914 {Angstrom}), N{sub 2} second positive group (3371 {Angstrom}), selected N{sub 2} Lyman-Birge-Hopfields bands (1325, 1354, 1383, 1493, and all bands between 1700 and 1800 {Angstrom}), O I (1356 {Angstrom}), L{sub {alpha}} (1216 {Angstrom}), H{sub {beta}} (4861 {Angstrom}), and H{sub {alpha}} (6563 {Angstrom}). The yield at 1493 {Angstrom} also contains a contribution from N I (1493 {Angstrom}), which in fact dominates LBH emission. A major new result of this study is that the secondary electron flux produced by the proton-hydrogen atom aurora is much softer than that produced by the electron aurora. This increased softness is due to the fact that (for energies of aurora interest) cross sections for secondary electron flux produced by the proton-hydrogen atom aurora is much softer than that produced by the electron aurora. This increased softness is due to the fact that (for energies of auroral interest) cross sections for secondary electron production by proton and hydrogen atom impact decrease exponentially with increasing secondary electron energy, whereas the cross sections for electron impact decrease as an inverse power law with increasing secondary energy.

  16. Beta-delayed particle emission from neutron-deficient isotopes in the Z approximately 50 region

    E-Print Network [OSTI]

    Tidemand-Petersson, P; Klepper, O; Plochocki, A; Roeckl, E; Schardt, D; Zylicz, J

    1981-01-01T23:59:59.000Z

    Experimental studies of beta-delayed proton and alpha-particle emission from precursors in the region close to the double shell closure at N=Z=50 are described. The results range from identification of new precursors like /sup 96/Ag and /sup 103,105/Sn, to determination of branching ratios, feeding of excited levels after particle emission and the energy available for proton emission. Comparison of the results with statistical-model calculations points to a resonance in the beta-strength function in the decay of /sup 110,112/I, /sup 113/Xe, /sup 114,116/Cs and /sup 117/Ba. (39 refs).

  17. Proton-proton bremsstrahlung: Consequences of different on-shell-point conditions

    SciTech Connect (OSTI)

    Li, Yi; Liou, M. K.; Schreiber, W. M.; Gibson, B. F. [College of Physics and Technology, Guangxi University, Nanning, Guangxi 530004 (China); Department of Physics and Institute for Nuclear Theory, Brooklyn College of the City University of New York, Brooklyn, New York 11210 (United States); Department of Physics, College of Staten Island of the City University of New York, Staten Island, New York 10314 (United States); Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2011-09-15T23:59:59.000Z

    Background: Proton-proton bremsstrahlung (pp{gamma}) is investigated both theoretically and experimentally. The pp{gamma} amplitudes can be classified according to the number and location of on-shell points at which they are evaluated. Quantitative understanding of the effect on the pp{gamma} cross section of using different on-shell-point conditions is lacking, but it is essential to identifying the photon emission mechanism governing the pp{gamma} process. Method: Four different pp{gamma} amplitudes, which include four-on-shell-point amplitudes and one-on-shell-point amplitude, are generated from a realistic one-boson-exchange (ROBE) model for pp scattering. These ROBE amplitudes are used to investigate the consequence of using different on-shell-point conditions in calculating the pp{gamma} cross sections. Purpose: We verify the validity of the ROBE pp{gamma} amplitudes. We explore similarities between the four-on-shell-point ROBE and two-u-two-t special (TuTts) soft-photon pp{gamma} amplitudes and important differences with the one-on-shell-point ROBE and Low pp{gamma} amplitudes. We demonstrate that the precision Kernfysisch Versneller Instituut (KVI) data can only be described by the four-on-shell-point (ROBE or TuTts) amplitude. We use the ROBE four-on-shell-point amplitude and one-on-shell-point amplitude to investigate systematically the effect of using different on-shell-point conditions to calculate the pp{gamma} cross section. Furthermore, we identify a general principle that governs the process. This general principle is also applicable to other bremsstrahlung processes involving the scattering of two identical nucleons. Results: (i) The four-on-shell-point ROBE (or TuTts) amplitude describes the high-precision KVI data much better than does the one-on-shell-point ROBE (or Low) amplitude. Although the contribution from the anomalous magnetic moment of the proton is very significant, it does not completely dominate the KVI pp{gamma} cross sections. (ii) The four-on-shell-point ROBE (or TuTts) amplitude describes the TRIUMF data better than does the one-on-shell-point ROBE (or Low) amplitude. (iii) The effect on the pp{gamma} cross section of using different on-shell-point conditions is significant in the hard-photon region, i.e., for small proton scattering angles {theta} (={theta}{sub 3}={theta}{sub 4}, symmetric scattering angles) far from the elastic limit ({theta}{yields}45 deg.); in contrast, the effect becomes insignificant in the vicinity of the elastic limit. Near the limit as {theta} tends to 45 deg. (or as the photon energy K approaches zero), the four-on-shell-point and one-on-shell-point amplitudes approach one another, a general principle applicable to all bremsstrahlung processes because only kinematics is involved. Conclusion: The four-on-shell-point ROBE amplitude provides a quantitative description of pp{gamma} cross sections. The anomalous magnetic moment is an important component of the photon emission mechanism. The four-on-shell-point property of the full ROBE amplitude is essential to properly describing the complete range of the precision KVI data and the TRIUMF data, although the one-on-shell-point ROBE amplitude is adequate in the region near the elastic limit.

  18. Long-range azimuthal correlations in proton-proton and proton-nucleus collisions from the incoherent scattering of partons

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

    Ma, Guo -Liang [Chinese Academy of Sciences, Shanghai (China). Shanghai Institute of Applied Physics; Bzdak, Adam [Brookhaven National Laboratory (BNL), Upton, NY (United States). Riken BNL Research Center

    2014-12-01T23:59:59.000Z

    We show that the incoherent elastic scattering of partons, as present in a multi-phase transport model (AMPT), with a modest parton–parton cross-section of ?=1.5–3 mb?=1.5–3 mb, naturally explains the long-range two-particle azimuthal correlation as observed in proton–proton and proton–nucleus collisions at the Large Hadron Collider.

  19. ONE- AND TWO-PROTON INCLUSIVE SPECTRA IN 800 MeV PROTON-NUCLEUS COLLISIONS AND THE MEAN FREE PATH OF PROTONS IN NUCLEI

    E-Print Network [OSTI]

    Tanihata, I.

    2013-01-01T23:59:59.000Z

    path of 2. 5 fm si.ngle~proton data, absolute com~ parisonCAPT IONS Fig. 1. Single-proton inclusive spectra (a) andin (a) Arrows indicate the proton momenta Curves in (b) show

  20. Solution to the Proton Radius Problem

    E-Print Network [OSTI]

    D. Robson

    2015-01-27T23:59:59.000Z

    The relationship between the electric form factors for the proton in the rest frame and in the Breit momentum frame is used to provide a value for the difference in the mean squared charge radius of the proton evaluated in the two frames. Associating the muonic-hydrogen data analysis for the proton charge radius of 0.84087 fm with the rest frame and associating the electron scattering with the Breit frame yields a prediction 0f 0.87944 fm for the proton radius in the relativistic frame. The most recent value deduced via electron scattering from the proton is 0.877(6)fm so that the frame dependence used here yields a plausible solution to the proton radius puzzle.

  1. Neutron emission and fragment yield in high-energy fission

    SciTech Connect (OSTI)

    Grudzevich, O. T., E-mail: ogrudzevich@ippe.ru; Klinov, D. A. [Institute for Physics and Power Engineering (Russian Federation)] [Institute for Physics and Power Engineering (Russian Federation)

    2013-07-15T23:59:59.000Z

    The KRIS special library of spectra and emission probabilities in the decays of 1500 nuclei excited up to energies between 150 and 250 MeV was developed for correctly taking into account the decay of highly excited nuclei appearing as fission fragments. The emission of neutrons, protons, and photons was taken into account. Neutron emission fromprimary fragments was found to have a substantial effect on the formation of yields of postneutron nuclei. The library was tested by comparing the calculated and measured yields of products originating from the fission of nuclei that was induced by high-energy protons. The method for calculating these yields was tested on the basis of experimental data on the thermal-neutroninduced fission of {sup 235}U nuclei.

  2. Molecular Mechanism of Biological Proton Transport

    SciTech Connect (OSTI)

    Pomes, R.

    1998-09-01T23:59:59.000Z

    Proton transport across lipid membranes is a fundamental aspect of biological energy transduction (metabolism). This function is mediated by a Grotthuss mechanism involving proton hopping along hydrogen-bonded networks embedded in membrane-spanning proteins. Using molecular simulations, the authors have explored the structural, dynamic, and thermodynamic properties giving rise to long-range proton translocation in hydrogen-bonded networks involving water molecules, or water wires, which are emerging as ubiquitous H{sup +}-transport devices in biological systems.

  3. Mean transverse mass of hadrons in proton-proton reactions

    E-Print Network [OSTI]

    V. Yu. Vovchenko; D. V. Anchishkin; M. I. Gorenstein

    2015-01-23T23:59:59.000Z

    An energy dependence of the mean transverse mass $\\langle m_T\\rangle$ at mid-rapidity in proton-proton ($p+p$) reactions is studied within the ultra-relativistic quantum molecular dynamics (UrQMD). The UrQMD model predicts a nonmonotonous dependence of $\\langle m_T\\rangle$ on collision energy for several hadron species: for $\\pi^+$, $p$, $K^+$, and $\\Lambda$ the mean transverse mass has a maximum at the center of mass energy region $5\\le \\sqrt{s}\\le 8$ GeV. These results are a consequence of an interplay of two contributions: 1) excitations and decays of the baryonic resonances $N^*$ and $\\Delta$; 2) excitations and decays of the baryonic strings. The UrQMD results do not show any nonmonotonous dependence of $\\langle m_T\\rangle$ on $\\sqrt{s}$ for $\\pi^-$, $K^{-}$, and antiprotons. Whether a nonmonotonous dependence of $\\langle m_T\\rangle$ at mid-rapidity on the collision energy for $\\pi^+$, $p$, $K^+$, and $\\Lambda$ is relevant for real $p+p$ interactions will be soon checked experimentally by the NA61/SHINE Collaboration.

  4. Proton beam therapy control system

    DOE Patents [OSTI]

    Baumann, Michael A; Beloussov, Alexandre V; Bakir, Julide; Armon, Deganit; Olsen, Howard B; Salem, Dana

    2013-12-03T23:59:59.000Z

    A tiered communications architecture for managing network traffic in a distributed system. Communication between client or control computers and a plurality of hardware devices is administered by agent and monitor devices whose activities are coordinated to reduce the number of open channels or sockets. The communications architecture also improves the transparency and scalability of the distributed system by reducing network mapping dependence. The architecture is desirably implemented in a proton beam therapy system to provide flexible security policies which improve patent safety and facilitate system maintenance and development.

  5. Proton beam therapy control system

    DOE Patents [OSTI]

    Baumann, Michael A; Beloussov, Alexandre V; Bakir, Julide; Armon, Deganit; Olsen, Howard B; Salem, Dana

    2013-06-25T23:59:59.000Z

    A tiered communications architecture for managing network traffic in a distributed system. Communication between client or control computers and a plurality of hardware devices is administered by agent and monitor devices whose activities are coordinated to reduce the number of open channels or sockets. The communications architecture also improves the transparency and scalability of the distributed system by reducing network mapping dependence. The architecture is desirably implemented in a proton beam therapy system to provide flexible security policies which improve patent safety and facilitate system maintenance and development.

  6. Proton beam therapy control system

    DOE Patents [OSTI]

    Baumann, Michael A. (Riverside, CA); Beloussov, Alexandre V. (Bernardino, CA); Bakir, Julide (Alta Loma, CA); Armon, Deganit (Redlands, CA); Olsen, Howard B. (Colton, CA); Salem, Dana (Riverside, CA)

    2008-07-08T23:59:59.000Z

    A tiered communications architecture for managing network traffic in a distributed system. Communication between client or control computers and a plurality of hardware devices is administered by agent and monitor devices whose activities are coordinated to reduce the number of open channels or sockets. The communications architecture also improves the transparency and scalability of the distributed system by reducing network mapping dependence. The architecture is desirably implemented in a proton beam therapy system to provide flexible security policies which improve patent safety and facilitate system maintenance and development.

  7. Proton beam therapy control system

    DOE Patents [OSTI]

    Baumann, Michael A. (Riverside, CA); Beloussov, Alexandre V. (San Bernardino, CA); Bakir, Julide (Alta Loma, CA); Armon, Deganit (Longmeadow, MA); Olsen, Howard B. (Irvine, CA); Salem, Dana (Riverside, CA)

    2010-09-21T23:59:59.000Z

    A tiered communications architecture for managing network traffic in a distributed system. Communication between client or control computers and a plurality of hardware devices is administered by agent and monitor devices whose activities are coordinated to reduce the number of open channels or sockets. The communications architecture also improves the transparency and scalability of the distributed system by reducing network mapping dependence. The architecture is desirably implemented in a proton beam therapy system to provide flexible security policies which improve patent safety and facilitate system maintenance and development.

  8. Real Compton Scattering from the Proton

    E-Print Network [OSTI]

    Alan M. Nathan

    1999-08-31T23:59:59.000Z

    Real Compton Scattering on the proton in the hard scattering regime is investigated. Recent theoretical developments are reviewed. Plans for new experimental studies at Jefferson Laboratory are presented.

  9. World's Thinnest Proton Channel | ornl.gov

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

    show that experimental observations of unimpeded proton transfer throughsingle-layer graphene occur via a classic "bucket-line" mechanism first proposed in 1806. Graphene is a...

  10. Scientists examine proton radiography of brain mockup

    E-Print Network [OSTI]

    the proton radiography team in this effort funded in part by the NNSA. Additional researchers include Fesseha Alamos National Security, LLC for the Department of Energy's NNSA #12;

  11. Controlling proton source speeds catalyst | EMSL

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

    speeds catalyst Controlling proton source speeds catalyst Released: April 29, 2013 Nickel-based catalyst three times faster with adjustments to key acid Research showing that...

  12. Determining the size of the proton

    E-Print Network [OSTI]

    N. G. Kelkar; F. Garcia Daza; M. Nowakowski

    2012-08-02T23:59:59.000Z

    A measurement of the Lamb shift of 49,881.88(76) GHz in muonic hydrogen in conjunction with theoretical estimates of the proton structure effects was recently used to deduce an accurate but rather small radius of the proton. Such an important shift in the understanding of fundamental values needs reconfirmation. Using a different approach with electromagnetic form factors of the proton, we obtain a new expression for the transition energy, $\\Delta = E_{2P_{{3}/{2}}}^{f=2} - E_{2S_{{1}/{2}}}^{f=1}$, in muonic hydrogen and deduce a proton radius, $r_p = 0.831$ fm.

  13. Low temperature proton conducting oxide devices

    DOE Patents [OSTI]

    Armstrong, Timothy R. (Clinton, TN); Payzant, Edward A. (Oak Ridge, TN); Speakman, Scott A. (Oak Ridge, TN); Greenblatt, Martha (Highland Park, NJ)

    2008-08-19T23:59:59.000Z

    A device for conducting protons at a temperature below 550.degree. C. includes a LAMOX ceramic body characterized by an alpha crystalline structure.

  14. Call issued for Proton Radiography Facility proposals

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

    into FY17. January 5, 2015 Amy Clarke and Seth Imhoff of Materials Technology-Metallurgy (MST-6) align a copper density calibration object for a proton radiography...

  15. Reconstruction for proton computed tomography by tracing proton trajectories: A Monte Carlo study

    E-Print Network [OSTI]

    Reconstruction for proton computed tomography by tracing proton trajectories: A Monte Carlo study 11 January 2006; published 22 February 2006 Proton computed tomography pCT has been explored computed tomography pCT has several potential ad- vantages in medical applications. Its favorable dose

  16. Measurement of proton and anti-proton intensities in the Tevatron Collider

    SciTech Connect (OSTI)

    Stephen Pordes et al.

    2003-06-04T23:59:59.000Z

    This paper describes the techniques used to measure the intensities of the proton (p) and anti-proton ({bar p}) beams in the Tevatron collider. The systems provide simultaneous measurements of the intensity of the 36 proton and 36 antiproton bunches and their longitudinal profiles.

  17. A separation of electrons and protons in the GAMMA-400 gamma-ray telescope

    E-Print Network [OSTI]

    Leonov, A A; Bonvicini, V; Topchiev, N P; Adriani, O; Aptekar, R L; Arkhangelskaja, I V; Arkhangelskiy, A I; Bergstrom, L; Berti, E; Bigongiari, G; Bobkov, S G; Boezio, M; Bogomolov, E A; Bonechi, S; Bongi, M; Bottai, S; Castellini, G; Cattaneo, P W; Cumani, P; Dedenko, G L; De Donato, C; Dogiel, V A; Gorbunov, M S; Gusakov, Yu V; Hnatyk, B I; Kadilin, V V; Kaplin, V A; Kaplun, A A; Kheymits, M D; Korepanov, V E; Larsson, J; Loginov, V A; Longo, F; Maestro, P; Marrocchesi, P S; Mikhailov, V V; Mocchiutti, E; Moiseev, A A; Mori, N; Moskalenko, I V; Naumov, P Yu; Papini, P; Pearce, M; Picozza, P; Popov, A V; Rappoldi, A; Ricciarini, S; Runtso, M F; Ryde, F; Serdin, O V; Sparvoli, R; Spillantini, P; Suchkov, S I; Tavani, M; Taraskin, A A; Tiberio, A; Tyurin, E M; Ulanov, M V; Vacchi, A; Vannuccini, E; Vasilyev, G I; Yurkin, Yu T; Zampa, N; Zirakashvili, V N; Zverev, V G

    2015-01-01T23:59:59.000Z

    The GAMMA-400 gamma-ray telescope is intended to measure the fluxes of gamma rays and cosmic-ray electrons and positrons in the energy range from 100 MeV to several TeV. Such measurements concern with the following scientific goals: search for signatures of dark matter, investigation of gamma-ray point and extended sources, studies of the energy spectra of Galactic and extragalactic diffuse emission, studies of gamma-ray bursts and gamma-ray emission from the active Sun, as well as high-precision measurements of spectra of high-energy electrons and positrons, protons, and nuclei up to the knee. The main components of cosmic rays are protons and helium nuclei, whereas the part of lepton component in the total flux is ~10E-3 for high energies. In present paper, the capability of the GAMMA-400 gamma-ray telescope to distinguish electrons and positrons from protons in cosmic rays is investigated. The individual contribution to the proton rejection is studied for each detector system of the GAMMA-400 gamma-ray tel...

  18. Driving Down Diesel Emissions

    E-Print Network [OSTI]

    Harley, Robert

    2013-01-01T23:59:59.000Z

    Turnover on Drayage Truck Emissions at the Port of Oakland,”actions to clean up port truck emissions in Oakland serve asTurnover on Drayage Truck Emissions at the Port of Oakland,”

  19. Cadmium Biosorption Rate in Protonated Sargassum Biomass

    E-Print Network [OSTI]

    Volesky, Bohumil

    Cadmium Biosorption Rate in Protonated Sargassum Biomass J I N B A I Y A N G A N D B O H U M I L V Sargassum fluitans biomass was accompanied by the release of hydrogen protons from the biomass. The uptake the overall biosorption rate of cadmium ions in flat seaweed biomass particles. The overall biosorption

  20. Reoptimising Front End with proton Chris Rogers,

    E-Print Network [OSTI]

    McDonald, Kirk

    ;Optimisation Routine 1D Model RF Cavity model Energy gain is sine wave Standard transit time factor absorber time_energy_movie-100mm.avi #12;Optimisation Routine Performance in ICOOL Longitudinal emittance... Optimisation using a simple 1D model works when no proton absorber Introducing a proton absorber screws up

  1. Simulation of proton radiography terminal at IMP

    E-Print Network [OSTI]

    Yan, Yan; Huang, Zhi-Wu; Wang, Jie; Yao, Ze-En; Wang, Jun-Run; Wei, Zheng; Yang, Jian-Cheng; Yuan, You-Jin

    2015-01-01T23:59:59.000Z

    Proton radiography is used for advanced hydrotesting as a new type radiography technology due to its powerful penetration capability and high detection efficiency. A new proton radiography terminal will be developed to radiograph static samples at Institute of Modern Physics of Chinese Academy of Science (IMP-CAS). The proton beam with the maximum energy of 2.6 GeV will be produced by Heavy Ion Research Facility in Lanzhou-Cooling Storage Ring (HIRFL-CSR). The proton radiography terminal consists of the matching magnetic lens and the Zumbro lens system. In this paper, the design scheme and all optic parameters of this beam terminal for 2.6GeV proton energy are presented by simulating the beam optics using WINAGILE code. My-BOC code is used to test the particle tracking of proton radiography beam line. Geant4 code and G4beamline code are used for simulating the proton radiography system. The results show that the transmission efficiency of proton without target is 100%, and the effect of secondary particles ca...

  2. PROTON AND DEUTERIUM NMR EXPERIMENTS IN ZERO FIELD

    E-Print Network [OSTI]

    Millar, J.M.

    2010-01-01T23:59:59.000Z

    Example of Isolated Proton Pair Practical Considerations TheJ J vi i A). B). C). IV. V. Proton Zero Field Spectra Effectcompared to that between protons, it can exert a profound

  3. Proton conducting ceramic membranes for hydrogen separation

    DOE Patents [OSTI]

    Elangovan, S. (South Jordan, UT); Nair, Balakrishnan G. (Sandy, UT); Small, Troy (Midvale, UT); Heck, Brian (Salt Lake City, UT)

    2011-09-06T23:59:59.000Z

    A multi-phase proton conducting material comprising a proton-conducting ceramic phase and a stabilizing ceramic phase. Under the presence of a partial pressure gradient of hydrogen across the membrane or under the influence of an electrical potential, a membrane fabricated with this material selectively transports hydrogen ions through the proton conducting phase, which results in ultrahigh purity hydrogen permeation through the membrane. The stabilizing ceramic phase may be substantially structurally and chemically identical to at least one product of a reaction between the proton conducting phase and at least one expected gas under operating conditions of a membrane fabricated using the material. In a barium cerate-based proton conducting membrane, one stabilizing phase is ceria.

  4. Proton radioactivity with a Yukawa effective interaction

    E-Print Network [OSTI]

    T. R. Routray; S. K. Tripathy; B. B. Dash; B. Behera; D. N. Basu

    2011-04-26T23:59:59.000Z

    The half lives of proton radioactivity of proton emitters are investigated theoretically. Proton-nucleus interaction potentials are obtained by folding the densities of the daughter nuclei with a finite range effective nucleon-nucleon interaction having Yukawa form. The Wood-Saxon density distributions for the nuclei used in calculating the nuclear as well as the Coulomb interaction potentials are predictions of the interaction. The quantum mechanical tunneling probability is calculated within the WKB framework. These calculations provide reasonable estimates for the observed proton radioactivity lifetimes. The effects of neutron-proton effective mass splitting in neutron rich asymmetric matter as well as the nuclear matter incompressibility on the decay probability are investigated.

  5. Atomistic Simulation of Water Percolation and Proton Hopping...

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

    Water Percolation and Proton Hopping in Nafion Fuel Cell Membrane. Atomistic Simulation of Water Percolation and Proton Hopping in Nafion Fuel Cell Membrane. Abstract: We have...

  6. Molecular Dynamics Study of the Proposed Proton Transport Pathways...

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

    Dynamics Study of the Proposed Proton Transport Pathways in FeFe-Hydrogenase. Molecular Dynamics Study of the Proposed Proton Transport Pathways in FeFe-Hydrogenase. Abstract:...

  7. Conformational Dynamics and Proton Relay Positioning in Nickel...

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

    Dynamics and Proton Relay Positioning in Nickel Catalysts for Hydrogen Production and Oxidation. Conformational Dynamics and Proton Relay Positioning in Nickel Catalysts for...

  8. Proton Exchange Membrane Fuel Cells for Electrical Power Generation...

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

    Proton Exchange Membrane Fuel Cells for Electrical Power Generation On-Board Commercial Airplanes Proton Exchange Membrane Fuel Cells for Electrical Power Generation On-Board...

  9. Oct. 25 Lecture Highlights Treatment Technology of HU's Proton...

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

    Oct. 25 Lecture Highlights Treatment Technology of HU's Proton Therapy Institute Cynthia Keppel Hampton University Proton Therapy Institute Scientific and Technical Director,...

  10. Computation of the Redox and Protonation Properties of Quinones...

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

    Computation of the Redox and Protonation Properties of Quinones: Towards the Prediction of Redox Cycling Natural Products. Computation of the Redox and Protonation Properties of...

  11. Multiwavelength Thermal Emission

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    Multiwavelength Astronomy NASA #12;Thermal Emission #12;Thermal Emission Non-thermal p-p collisions Optical IR Radio/ Microwave sources of emission massive stars, WHIM, Ly many dust, cool objects-ray ~GeV Gamma-ray ~TeV sources of emission AGN, clusters, SNR, binaries, stars AGN (obscured), shocks

  12. Beta delayed alpha emission from the neutron deficient rare earth isotopes {sup 152}Tm and {sup 150}Ho

    SciTech Connect (OSTI)

    Nacher, E. [Instituto de Fisica Corpuscular, CSIC - Univ. de Valencia (Spain); Instituto de Estructura de la Materia, CSIC, Madrid (Spain); Tain, J. L.; Rubio, B.; Algora, A.; Estevez Aguado, M. E.; Gadea, A. [Instituto de Fisica Corpuscular, CSIC - Univ. de Valencia (Spain); Batist, L. [PNPI, Gatchina (Russian Federation); Briz, J. A. [Instituto de Estructura de la Materia, CSIC, Madrid (Spain); Cano-Ott, D. [CIEMAT, Madrid (Spain); Doering, J.; Mukha, I.; Plettner, C.; Roeckl, E. [GSI, Darmstadt (Germany); Gierlik, M.; Janas, Z. [University of Warsaw (Poland)

    2011-11-30T23:59:59.000Z

    The study of beta-delayed proton emission is a well known method to aid the determination of the beta strength distribution in nuclei far from the stability line. At the neutron deficient side of the nuclear chart the process of proton or alpha emission from excited states is energetically allowed when one goes far enough from stability. However, beta-delayed alphas have seldom been measured for nuclei heavier than A = 20. Here we present a study of the beta-delayed alpha-particle emission from {sup 152}Tm and {sup 150}Ho and their importance in the full B(GT) distribution.

  13. Attosecond neutron Compton scattering from protons

    E-Print Network [OSTI]

    C. Aris Chatzidimitriou-Dreismann

    2007-02-01T23:59:59.000Z

    The effect of "anomalous" scattering of neutrons and electrons from protons in the electron-volt energy-transfer range is considered, and related experimental results are mentioned. A recent independent confirmation of this effect with a new data analysis procedure is presented. Due to the very short characteristic scattering time, there is no well defined separation of time scales of electronic and protonic motions. An outline of a proposed theoretical interpretation is presented, which is based on the fact that scattering protons represent \\textit{open} quantum systems, thus being subject to decoherence.

  14. Memory device using movement of protons

    DOE Patents [OSTI]

    Warren, William L. (900 N. Randolph St., Arlington, VA 22203); Vanheusden, Karel J. R. (8401 Spain Rd., Albuquerque, NM 87111); Fleetwood, Daniel M. (5513 Estrellita del Norte, NE., Albuquerque, NM 87111); Devine, Roderick A. B. (12 Impasse de la Liberation, 38950 St. Martin le Vinoux, FR); Archer, Leo B. (3108 Vicky Ct., Garland, TX 75044); Brown, George A. (1512 Ridgeview Dr., Arlington, TX 76012-1940); Wallace, Robert M. (428 Park Bend Dr., Richardson, TX 75081)

    2000-01-01T23:59:59.000Z

    An enhancement of an electrically written memory element utilizing the motion of protons within a dielectric layer surrounded by layers on either side to confine the protons within the dielectric layer with electrode means attached to the surrounding layers to change the spatial position of the protons within the dielectric layer. The device is preferably constructed as a silicon-silicon dioxide-silicon layered structure with the protons being introduced to the structure during an anneal in an atmosphere containing hydrogen gas. Device operation is enhanced by concluding this anneal step with a sudden cooling. The device operates at low power, is preferably nonvolatile, is radiation tolerant, and is compatible with convention silicon MOS processing for integration with other microelectronics elements on the same silicon substrate.

  15. Memory device using movement of protons

    DOE Patents [OSTI]

    Warren, William L. (Albuquerque, NM); Vanheusden, Karel J. R. (Albuquerque, NM); Fleetwood, Daniel M. (Albuquerque, NM); Devine, Roderick A. B. (St. Martin le Vinoux, FR)

    1998-01-01T23:59:59.000Z

    An electrically written memory element utilizing the motion of protons within a dielectric layer surrounded by layers on either side to confine the protons within the dielectric layer with electrode means attached to the surrounding layers to change the spatial position of the protons within the dielectric layer. The device is preferably constructed as a silicon-silicon dioxide-silicon layered structure with the protons being introduced to the structure laterally through the exposed edges of the silicon dioxide layer during a high temperature anneal in an atmosphere containing hydrogen gas. The device operates at low power, is preferably nonvolatile, is radiation tolerant, and is compatible with convention silicon MOS processing for integration with other microelectronic elements on the same silicon substrate. With the addition of an optically active layer, the memory element becomes an electrically written, optically read optical memory element.

  16. Memory device using movement of protons

    DOE Patents [OSTI]

    Warren, W.L.; Vanheusden, K.J.R.; Fleetwood, D.M.; Devine, R.A.B.

    1998-11-03T23:59:59.000Z

    An electrically written memory element is disclosed utilizing the motion of protons within a dielectric layer surrounded by layers on either side to confine the protons within the dielectric layer with electrode means attached to the surrounding layers to change the spatial position of the protons within the dielectric layer. The device is preferably constructed as a silicon-silicon dioxide-silicon layered structure with the protons being introduced to the structure laterally through the exposed edges of the silicon dioxide layer during a high temperature anneal in an atmosphere containing hydrogen gas. The device operates at low power, is preferably nonvolatile, is radiation tolerant, and is compatible with convention silicon MOS processing for integration with other microelectronic elements on the same silicon substrate. With the addition of an optically active layer, the memory element becomes an electrically written, optically read optical memory element. 19 figs.

  17. Exclusive 0 electroproduction on transversely polarized protons

    E-Print Network [OSTI]

    Exclusive 0 electroproduction on transversely polarized protons A. Airapetian,12, 15 N. Akopov,26 Z. Akopov,26 E.C. Aschenauer,6 W. Augustyniak,25 A. Avetissian,26 E. Avetisyan,5 B. Ball,15 N. Bianchi,10 H

  18. Resolution of the Proton Spin Problem

    SciTech Connect (OSTI)

    F. Myhrer; A. W. Thomas

    2007-09-24T23:59:59.000Z

    A number of lines of investigation into the structure of the nucleon have converged to the point where we believe that one has a consistent explanation of the well known proton spin crisis.

  19. Low energy neutron-proton interactions

    E-Print Network [OSTI]

    Daub, Brian (Brian Hollenberg)

    2012-01-01T23:59:59.000Z

    There have been few measurements of cross sections for neutron-proton scattering and radiative capture below 1 MeV. Those measurements which do exist are at a small number of energies and are often inconsistent with ...

  20. Physics at a new Fermilab proton driver

    SciTech Connect (OSTI)

    Geer, Steve; /Fermilab

    2006-04-01T23:59:59.000Z

    In 2004, motivated by the recent exciting developments in neutrino physics, the Fermilab Long Range Planning Committee identified a new high intensity Proton Driver as an attractive option for the future. At the end of 2004 the APS ''Study on the Physics of Neutrinos'' concluded that the future US neutrino program should have, as one of its components, ''A proton driver in the megawatt class or above and neutrino superbeam with an appropriate very large detector capable of observing Cp violation and measuring the neutrino mass-squared differences and mixing parameters with high precision''. The presently proposed Fermilab Proton Driver is designed to accomplish these goals, and is based on, and would help develop, Linear Collider technology. In this paper the Proton Driver parameters are summarized, and the potential physics program is described.

  1. Memory device using movement of protons

    DOE Patents [OSTI]

    Warren, William L. (Albuquerque, NM); Vanheusden, Karel J. R. (Albuquerque, NM); Fleetwood, Daniel M. (Albuquerque, NM); Devine, Roderick A. B. (St. Martin le Vinoux, FR)

    2000-01-01T23:59:59.000Z

    An electrically written memory element utilizing the motion of protons within a dielectric layer surrounded by layers on either side to confine the protons within the dielectric layer with electrode means attached to the surrounding layers to change the spatial position of the protons within the dielectric layer. The device is preferably constructed as a silicon-silicon dioxide-silicon layered structure with the protons being introduced to the structure laterally through the exposed edges of the silicon dioxide layer during a high temperature anneal in an atmosphere containing hydrogen gas. The device operates at low power, is preferably nonvolatile, is radiation tolerant, and is compatible with convention silicon MOS processing for integration with other microelectronic elements on the same silicon substrate. With the addition of an optically active layer, the memory element becomes an electrically written, optically read optical memory element.

  2. Proton Transfer in Nucleobases is Mediated by Water Kirill Khistyaev,

    E-Print Network [OSTI]

    Krylov, Anna I.

    Proton Transfer in Nucleobases is Mediated by Water Kirill Khistyaev, Amir Golan, Ksenia B. Bravaya, and facilitating efficient proton transport through ion channels and interfaces. This study investigates proton and tunable vacuum ultraviolet synchrotron radiation, we show that water shuts down ionization-induced proton

  3. PhysicsHighlight Proton radiography at Los Alamos National Laboratory

    E-Print Network [OSTI]

    PhysicsHighlight Proton radiography at Los Alamos National Laboratory Proton Radiography, invented at Los Alamos National Laboratory, employs a high-energy proton beam to image the properties and behavior of materials driven by high explosives. A series of proton radiographs of disks (left to right) aluminum

  4. Leading proton production in deep inelastic scattering at HERA

    E-Print Network [OSTI]

    Leading proton production in deep inelastic 1 scattering at HERA 2 ZEUS Collaboration 3 Draft, with a #28;nal-state proton carrying a large fraction of the incoming proton energy, x L > 0 photon virtualities Q 2 > 3 GeV 2 and mass of the photon-proton sys- tem 45

  5. Investigation of proton focusing and conversion efficiency for proton fast ignition

    E-Print Network [OSTI]

    Bartal, Teresa Jean

    2012-01-01T23:59:59.000Z

    Protons from Ultra-short Pulse Laser Irradiated Foils. PhDintense laser (? 10 19 Wcm ?2 [9]. The short ultra intense

  6. Investigation of proton focusing and conversion efficiency for proton fast ignition

    E-Print Network [OSTI]

    Bartal, Teresa Jean

    2012-01-01T23:59:59.000Z

    After ignition, a thermonuclear burn wave spreads radiallythe shell to create the thermonuclear burn wave. At 10 keV,heating the plasma to thermonuclear temperatures. Protons

  7. Particle rapidity distribution in proton-nucleus collisions using the proton-contributor reference frame

    E-Print Network [OSTI]

    Gines Martinez-Garcia

    2014-08-14T23:59:59.000Z

    I define the proton-contributor reference frame in proton nucleus (p--A) collisions as the center of mass of the system formed by the proton and the participant nucleons of the nucleus. Assuming that the rapidity distribution of produced particles is symmetric in the proton-contributor reference frame, several measurements in p-Pb collisions at $\\sqrt{s_{\\rm NN}} = 5.02 {\\rm TeV}$ can be described qualitatively. These include rapidity distributions of charged particles, $J/\\psi$ and Z bosons.

  8. Statistical nature of cluster emission in nuclear liquid phase

    E-Print Network [OSTI]

    Y. G. Ma

    2002-03-23T23:59:59.000Z

    The emission of nuclear clusters is investigated within the framework of isospin dependent lattice gas model and classical molecular dynamics model. It is found that the emission of individual cluster which is heavier than proton is almost Poissonian except near the liquid gas phase transition point and the thermal scaling is observed by the linear Arrhenius plots which is made from the average multiplicity of each cluster versus the inverse of temperature in the nuclear liquid phase. It indicates of a statistical nature of such cluster emission in the models. The "emission barriers" which are the slopes of the Arrhenius plots are extracted as a function of the mass or charge number and fitted by the formula embodied with the contributions of the surface energy and Coulomb interaction. The possible influences of the source size, Coulomb interaction and "freeze-out" density and related physical implications are discussed.

  9. 200 MeV Proton Radiography Studies with a Hand Phantom Using a Prototype Proton CT Scanner

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    200 MeV Proton Radiography Studies with a Hand Phantom Using a Prototype Proton CT Scanner Tia.F.W. Sadrozinski, K. Schubert, R. Schulte, B. Schultze, D. Steinberg, M. Witt, A. Zatserklyaniy Abstract--Proton alignment and verification procedures for proton beam radiation therapy. The quality of the image, both

  10. BP's Perspective on Emissions Purdue Emissions Trading Workshop

    E-Print Network [OSTI]

    BP's Perspective on Emissions Trading Purdue Emissions Trading Workshop April 30, 2010 Mark - Government policies can create a carbon price via three primary mechanisms: - Emissions trading (BP's strong

  11. Excess Emissions (New Mexico)

    Broader source: Energy.gov [DOE]

    This regulation establishes requirements for a source whose operation results in an excess emission and to establish criteria for a source whose operation results in an excess emission to claim an...

  12. Emissions Trading and Social Justice

    E-Print Network [OSTI]

    Farber, Daniel A

    2011-01-01T23:59:59.000Z

    David  M.  Driesen,  Does  Emissions  Trading  Encourage  Jason  Coburn,  Emissions  Trading   and   Environmental  Szambelan,  U.S.  Emissions  Trading  Markets  for  SO 2  

  13. Clustering phenomena from two-particle angular correlations in proton-proton and heavy ion collisions

    E-Print Network [OSTI]

    Li, Wei, Ph. D. Massachusetts Institute of Technology

    2009-01-01T23:59:59.000Z

    Results on two-particle angular correlations in proton-proton (/-s = 200 and 410 GeV) ,Cu+Cu and Au+Au collisions (js = 200 GeV) are presented over a broad range of pseudorapidity ([eta]) and azimuthal angle ([phi]). The ...

  14. Proton-proton multiplicity distributions at LHC and the Pomeron intercept

    E-Print Network [OSTI]

    A. Capella; E. G. Ferreiro

    2013-01-15T23:59:59.000Z

    We compute the proton-proton multiplicity distributions at LHC energies in the framework of a multiple scattering model assuming a Poisson distribution for each inelastic collision. Multiple scattering is essential to broaden the multiplicity distribution. We obtain approximate KNO scaling for small pseudo-rapidity intervals ($|\\eta | < 0.5$) and sizable KNO scaling violations for larger ones, in agreement with experiment.

  15. $?$ and $?$ Production in Proton-Proton Collisions at E=13 TeV

    E-Print Network [OSTI]

    Leonard S. Kisslinger; Debasish Das

    2015-05-27T23:59:59.000Z

    This article is an extension of our recent studies of $\\Psi$ and $\\Upsilon$ production cross sections in proton-proton collisions at the LHC with E=$\\sqrt{s}$=8.0 TeV to E=13 TeV

  16. $?$ and $?$ Production in Proton-Proton Collisions at E=13 TeV

    E-Print Network [OSTI]

    Leonard S. Kisslinger; Debasish Das

    2015-02-02T23:59:59.000Z

    This article is an extension of our recent studies of $\\Psi$ and $\\Upsilon$ production cross sections in proton-proton collisions at the LHC with E=$\\sqrt{s}$=8.0 TeV to E=13 TeV

  17. Regulation of GHG emissions from transportation fuels: Emission quota versus emission intensity standard

    E-Print Network [OSTI]

    Rajagopal, Deepak

    2010-01-01T23:59:59.000Z

    Derivation of average cost of emission reduction by blending?) and ? respectively. GHG emissions per unit of blend is, ?+ ?? i Reduction in GHG emissions with respect to unblended

  18. Effect of proton-proton Coulomb repulsion on soft dipole excitations of light proton-rich nuclei

    E-Print Network [OSTI]

    T. Oishi; K. Hagino; H. Sagawa

    2011-09-14T23:59:59.000Z

    We perform three-body model calculations for soft dipole excitations of the proton-rich Borromean nucleus $^{17}$Ne. To this end, we assume that $^{17}$Ne takes the $^{15}$O+p+p structure, in which the two valence protons are excited from the $0^+$ ground state configuration to $1^-$ continuum states. We employ a density-dependent contact force for the nuclear part of the pairing interaction, and discretize the continuum states with the box boundary condition. We show by explicitly including the Coulomb interaction between the valence protons that the Coulomb repulsion does not significantly alter the E1 strength distribution. We point out that the effect of the Coulomb repulsion in fact can be well simulated by renormalizing the nuclear pairing interaction.

  19. A Detector for Proton Computed Tomography

    SciTech Connect (OSTI)

    Blazey, G.; et al.,

    2013-12-06T23:59:59.000Z

    Radiation therapy is a widely recognized treatment for cancer. Energetic protons have distinct features that set them apart from photons and make them desirable for cancer therapy as well as medical imaging. The clinical interest in heavy ion therapy is due to the fact that ions deposit almost all of their energy in a sharp peak – the Bragg peak- at the very end of their path. Proton beams can be used to precisely localize a tumor and deliver an exact dose to the tumor with small doses to the surrounding tissue. Proton computed tomography (pCT) provides direct information on the location on the target tumor, and avoids position uncertainty caused by treatment planning based on imaging with X-ray CT. The pCT project goal is to measure and reconstruct the proton relative stopping power distribution directly in situ. To ensure the full advantage of cancer treatment with 200 MeV proton beams, pCT must be realized.

  20. Energy Production Demonstrator for Megawatt Proton Beams

    E-Print Network [OSTI]

    Pronskikh, Vitaly S; Novitski, Igor; Tyutyunnikov, Sergey I

    2014-01-01T23:59:59.000Z

    A preliminary study of the Energy Production Demonstrator (EPD) concept - a solid heavy metal target irradiated by GeV-range intense proton beams and producing more energy than consuming - is carried out. Neutron production, fission, energy deposition, energy gain, testing volume and helium production are simulated with the MARS15 code for tungsten, thorium, and natural uranium targets in the proton energy range 0.5 to 120 GeV. This study shows that the proton energy range of 2 to 4 GeV is optimal for both a natU EPD and the tungsten-based testing station that would be the most suitable for proton accelerator facilities. Conservative estimates, not including breeding and fission of plutonium, based on the simulations suggest that the proton beam current of 1 mA will be sufficient to produce 1 GW of thermal output power with the natU EPD while supplying < 8% of that power to operate the accelerator. The thermal analysis shows that the concept considered has a problem due to a possible core meltdown; however...

  1. Energy Production Demonstrator for Megawatt Proton Beams

    E-Print Network [OSTI]

    Vitaly S. Pronskikh; Nikolai Mokhov; Igor Novitski; Sergey I. Tyutyunnikov

    2014-07-16T23:59:59.000Z

    A preliminary study of the Energy Production Demonstrator (EPD) concept - a solid heavy metal target irradiated by GeV-range intense proton beams and producing more energy than consuming - is carried out. Neutron production, fission, energy deposition, energy gain, testing volume and helium production are simulated with the MARS15 code for tungsten, thorium, and natural uranium targets in the proton energy range 0.5 to 120 GeV. This study shows that the proton energy range of 2 to 4 GeV is optimal for both a natU EPD and the tungsten-based testing station that would be the most suitable for proton accelerator facilities. Conservative estimates, not including breeding and fission of plutonium, based on the simulations suggest that the proton beam current of 1 mA will be sufficient to produce 1 GW of thermal output power with the natU EPD while supplying < 8% of that power to operate the accelerator. The thermal analysis shows that the concept considered has a problem due to a possible core meltdown; however, a number of approaches (a beam rastering, in first place) are suggested to mitigate the issue. The efficiency of the considered EPD as a Materials Test Station (MTS) is also evaluated in this study.

  2. Modelling proton transfer in water molecule chains

    E-Print Network [OSTI]

    Artem Korzhimanov; Mattias Marklund; Tatiana Shutova; Goran Samuelsson

    2011-08-22T23:59:59.000Z

    The process of protons transport in molecular water chains is of fundamental interest for many biological systems. Although many features of such systems can be analyzed using large-scale computational modeling, other features are better understood in terms of simplified model problems. Here we have tested, analytically and numerically, a model describing the classical proton hopping process in molecular water chains. In order to capture the main features of the proton hopping process in such molecular chains, we use a simplified model for our analysis. In particular, our discrete model describes a 1D chain of water molecules situated in an external protein channel structure, and each water molecule is allowed to oscillate around its equilibrium point in this system, while the protons are allowed to move along the line of neighboring oxygen atoms. The occurrence and properties of nonlinear solitary transport structures, allowing for much faster proton transport, are discussed, and the possible implications of these findings for biological systems are emphasized.

  3. Future Sulfur Dioxide Emissions

    SciTech Connect (OSTI)

    Smith, Steven J.; Pitcher, Hugh M.; Wigley, Tom M.

    2005-12-01T23:59:59.000Z

    The importance of sulfur dioxide emissions for climate change is now established, although substantial uncertainties remain. This paper presents projections for future sulfur dioxide emissions using the MiniCAM integrated assessment model. A new income-based parameterization for future sulfur dioxide emissions controls is developed based on purchasing power parity (PPP) income estimates and historical trends related to the implementation of sulfur emissions limitations. This parameterization is then used to produce sulfur dioxide emissions trajectories for the set of scenarios developed for the Special Report on Emission Scenarios (SRES). We use the SRES methodology to produce harmonized SRES scenarios using the latest version of the MiniCAM model. The implications, and requirements, for IA modeling of sulfur dioxide emissions are discussed. We find that sulfur emissions eventually decline over the next century under a wide set of assumptions. These emission reductions result from a combination of emission controls, the adoption of advanced electric technologies, and a shift away from the direct end use of coal with increasing income levels. Only under a scenario where incomes in developing regions increase slowly do global emission levels remain at close to present levels over the next century. Under a climate policy that limits emissions of carbon dioxide, sulfur dioxide emissions fall in a relatively narrow range. In all cases, the relative climatic effect of sulfur dioxide emissions decreases dramatically to a point where sulfur dioxide is only a minor component of climate forcing by the end of the century. Ecological effects of sulfur dioxide, however, could be significant in some developing regions for many decades to come.

  4. Polarization measurement of laser-accelerated protons

    SciTech Connect (OSTI)

    Raab, Natascha; Engels, Ralf; Engin, Ilhan; Greven, Patrick; Holler, Astrid; Lehrach, Andreas; Maier, Rudolf [Institut für Kernphysik and Jülich Center for Hadron Physics, Forschungszentrum Jülich, 52425 Jülich (Germany)] [Institut für Kernphysik and Jülich Center for Hadron Physics, Forschungszentrum Jülich, 52425 Jülich (Germany); Büscher, Markus, E-mail: m.buescher@fz-juelich.de [Institut für Kernphysik and Jülich Center for Hadron Physics, Forschungszentrum Jülich, 52425 Jülich (Germany) [Institut für Kernphysik and Jülich Center for Hadron Physics, Forschungszentrum Jülich, 52425 Jülich (Germany); Peter Grünberg Institut (PGI-6), Forschungszentrum Jülich, 52425 Jülich (Germany); Institute for Laser- and Plasma Physics, Heinrich-Heine Universität Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf (Germany); Cerchez, Mirela; Swantusch, Marco; Toncian, Monika; Toncian, Toma; Willi, Oswald [Institute for Laser- and Plasma Physics, Heinrich-Heine Universität Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf (Germany)] [Institute for Laser- and Plasma Physics, Heinrich-Heine Universität Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf (Germany); Gibbon, Paul; Karmakar, Anupam [Institute for Advanced Simulation, Jülich Supercomputing Centre, Forschungszentrum Jülich, 52425 Jülich (Germany)] [Institute for Advanced Simulation, Jülich Supercomputing Centre, Forschungszentrum Jülich, 52425 Jülich (Germany)

    2014-02-15T23:59:59.000Z

    We report on the successful use of a laser-driven few-MeV proton source to measure the differential cross section of a hadronic scattering reaction as well as on the measurement and simulation study of polarization observables of the laser-accelerated charged particle beams. These investigations were carried out with thin foil targets, illuminated by 100 TW laser pulses at the Arcturus laser facility; the polarization measurement is based on the spin dependence of hadronic proton scattering off nuclei in a Silicon target. We find proton beam polarizations consistent with zero magnitude which indicates that for these particular laser-target parameters the particle spins are not aligned by the strong magnetic fields inside the laser-generated plasmas.

  5. Proton radius puzzle and large extra dimensions

    E-Print Network [OSTI]

    Li-Bang Wang; Wei-Tou Ni

    2013-05-23T23:59:59.000Z

    We propose a theoretical scenario to solve the proton radius puzzle which recently arises from the muonic hydrogen experiment. In this framework, 4 + n dimensional theory is incorporated with modified gravity. The extra gravitational interaction between the proton and muon at very short range provides an energy shift which accounts for the discrepancy between spectroscopic results from muonic and electronic hydrogen experiments. Assuming the modified gravity is a small perturbation to the existing electromagnetic interaction, we find the puzzle can be solved with stringent constraint on the range of the new force. Our result not only provides a possible solution to the proton radius puzzle but also suggest a direction to test new physics at very small length scale.

  6. Elastic and Proton Dynamics of the DNA

    E-Print Network [OSTI]

    V. L. Golo

    2008-03-28T23:59:59.000Z

    The subject of this report is the dynamics of elastic system in conjunction with hydrogen bonds of the DNA. We draw attention to the draw-back of the familiar rod model of the DNA, and make a case of constructing models that could accommodate the intrinsic structure of the DNA. In this respect studying the interplay among the elastic system and the protons of the DNA, is of interest, for it could accommodate the inter-strand as well as the tunneling modes of protons. Following this direction, we come to the conclusion that the elastic-proton dynamics may have a bearing on biophysics of the DNA. The phenomenon of point mutations is discussed within this framework.

  7. Neutrino pair emission due to scattering of electrons off fluxoids in superfluid neutron star cores

    E-Print Network [OSTI]

    A. D. Kaminker; D. G. Yakovlev; P. Haensel

    1997-02-18T23:59:59.000Z

    We study the emission of neutrinos, resulting from the scattering of electrons off magnetic flux tubes (fluxoids) in the neutron star cores with superfluid (superconducting) protons. In the absence of proton superfluidity (T> T_{cp}), this process transforms into the well known electron synchrotron emission of neutrino pairs in a locally uniform magnetic field B, with the neutrino energy loss rate Q proportional to B^2 T^5. For temperatures T not much below T_{cp}, the synchrotron regime (Q \\propto T^5) persists and the emissivity Q can be amplified by several orders of magnitude due to the appearance of the fluxoids and associated enhancement of the field within them. For lower T, the synchrotron regime transforms into the bremsstrahlung regime (Q \\propto T^6) similar to the ordinary neutrino-pair bremsstrahlung of electrons which scatter off atomic nuclei. We calculate Q numerically and represent our results through a suitable analytic fit. In addition, we estimate the emissivities of two other neutrino-production mechanisms which are usually neglected -- neutrino-pair bremsstrahlung processes due to electron-proton and electron-electron collisions. We show that the electron-fluxoid and electron-electron scattering can provide the main neutrino production mechanisms in the neutron star cores with highly superfluid protons and neutrons at T scattering is significant if the initial, locally uniform magnetic field B > 10^{13} G.

  8. Non-thermal emission from Galaxy Clusters and future observations with the FERMI gamma-ray telescope and LOFAR

    E-Print Network [OSTI]

    G. Brunetti

    2008-10-03T23:59:59.000Z

    FERMI (formely GLAST) and LOFAR will shortly provide crucial information on the non-thermal components (relativistic particles and magnetic field) in galaxy clusters. After discussing observational facts that already put constraints on the properties and origin of non-thermal components, I will report on the emission spectrum from galaxy clusters as expected in the context of general calculations in which relativistic particles (protons and secondary electrons due to proton-proton collisions) interact with MHD turbulence generated in the cluster volume during cluster-cluster mergers. In this scenario (known as re-acceleration scenario) diffuse cluster-scale radio emission is produced in massive clusters during merging events, while gamma ray emission, at some level, is expected to be common in clusters. Expectations of interest for LOFAR and FERMI are also briefly discussed.

  9. Photo-Production of Proton Antiproton Pairs

    SciTech Connect (OSTI)

    Paul Eugenio; Burnham Stokes

    2007-02-01T23:59:59.000Z

    Results are reported on the reaction gammap --> ppp-bar . A high statistic data set was obtained at the Thomas Jefferson National Accelerator Facility utilizing the CLAS detector and a tagged photon beam of 4.8 to 5.2 GeV incident on a liquid hydrogen target. The focus of this study was to search for possible intermediate resonances which decay to proton-antiproton. Both final state protons were detected in the CLAS apparatus whereas the antiproton was identified via missing mass. General features of the data are presented along with results on narrow and broad resonance studies.

  10. Photo-Production of Proton Antiproton Pairs

    SciTech Connect (OSTI)

    Eugenio, Paul; Stokes, Burnham [Department of Physics, Florida State University, Tallahassee, FL (United States)

    2007-02-27T23:59:59.000Z

    Results are reported on the reaction {gamma}p {yields} ppp-bar. A high statistic data set was obtained at the Thomas Jefferson National Accelerator Facility utilizing the CLAS detector and a tagged photon beam of 4.8 to 5.2 GeV incident on a liquid hydrogen target. The focus of this study was to search for possible intermediate resonances which decay to proton-antiproton. Both final state protons were detected in the CLAS apparatus whereas the antiproton was identified via missing mass. General features of the data are presented along with results on narrow and broad resonance studies.

  11. Lorentz Coherence and the Proton Form Factor

    E-Print Network [OSTI]

    Kim, Young S

    2015-01-01T23:59:59.000Z

    The dipole cutoff behavior for the proton form factor has been and still is one of the major issues in high-energy physics. It is shown that this dipole behavior comes from the coherence between the Lorentz contraction of the proton size and the decreasing wavelength of the incoming photon signal. The contraction rates are the same for both cases. This form of coherence is studied also in the momentum-energy space. The coherence effect in this space can be explained in terms of two overlapping wave functions.

  12. Lorentz Coherence and the Proton Form Factor

    E-Print Network [OSTI]

    Young S. Kim

    2015-02-28T23:59:59.000Z

    The dipole cutoff behavior for the proton form factor has been and still is one of the major issues in high-energy physics. It is shown that this dipole behavior comes from the coherence between the Lorentz contraction of the proton size and the decreasing wavelength of the incoming photon signal. The contraction rates are the same for both cases. This form of coherence is studied also in the momentum-energy space. The coherence effect in this space can be explained in terms of two overlapping wave functions.

  13. Quantum gravitational proton decay at high temperature

    E-Print Network [OSTI]

    Ulf H. Danielsson

    2005-12-29T23:59:59.000Z

    One of the most important challenges of contemporary physics is to find experimental signatures of quantum gravity. It is expected that quantum gravitational effects lead to proton decay but on time scales way beyond what is of any relevance to experiments. At non-zero temperatures there are reasons to believe that the situation is much more favourable. We will argue that at the temperatures and densities reached at present and future fusion facilities there is a realistic possibility that proton decay could be detectable.

  14. Single Spin Asymmetries in Proton-Proton and Proton-Neutron Scattering at 820 GeV

    E-Print Network [OSTI]

    Wolf-Dieter Nowak

    1995-01-11T23:59:59.000Z

    The physics case is summarised for the investigation of high energy spin phenomena by placing an internal polarised target into HERA's unpolarised proton beam. The luminosity and experimental sensitivity are discussed. Estimating the physics reach of single spin asymmetries in different final states reveals a considerable physics potential in testing the spin sector of perturbative QCD.

  15. Comparison of Source Images for protons, $?^-$'s and $?$'s in 6 AGeV Au+Au collisions

    E-Print Network [OSTI]

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

    2003-07-16T23:59:59.000Z

    Source images are extracted from two-particle correlations constructed from strange and non-strange hadrons produced in 6 AGeV Au + Au collisions. Very different source images result from pp vs p$\\Lambda$ vs $\\pi^-\\pi^-$ correlations. These observations suggest important differences in the space-time emission histories for protons, pions and neutral strange baryons produced in the same events.

  16. Fan-beam intensity modulated proton therapy

    SciTech Connect (OSTI)

    Hill, Patrick [Department of Radiation Oncology, University of Iowa Hospitals and Clinics, Iowa City, Iowa 52242 (United States)] [Department of Radiation Oncology, University of Iowa Hospitals and Clinics, Iowa City, Iowa 52242 (United States); Westerly, David [Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, Colorado 80045 (United States)] [Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, Colorado 80045 (United States); Mackie, Thomas [Medical Devices, Morgridge Institute for Research, University of Wisconsin, Madison, Wisconsin 53715 (United States)] [Medical Devices, Morgridge Institute for Research, University of Wisconsin, Madison, Wisconsin 53715 (United States)

    2013-11-15T23:59:59.000Z

    Purpose: This paper presents a concept for a proton therapy system capable of delivering intensity modulated proton therapy using a fan beam of protons. This system would allow present and future gantry-based facilities to deliver state-of-the-art proton therapy with the greater normal tissue sparing made possible by intensity modulation techniques.Methods: A method for producing a divergent fan beam of protons using a pair of electromagnetic quadrupoles is described and particle transport through the quadrupole doublet is simulated using a commercially available software package. To manipulate the fan beam of protons, a modulation device is developed. This modulator inserts or retracts acrylic leaves of varying thickness from subsections of the fan beam. Each subsection, or beam channel, creates what effectively becomes a beam spot within the fan area. Each channel is able to provide 0–255 mm of range shift for its associated beam spot, or stop the beam and act as an intensity modulator. Results of particle transport simulations through the quadrupole system are incorporated into the MCNPX Monte Carlo transport code along with a model of the range and intensity modulation device. Several design parameters were investigated and optimized, culminating in the ability to create topotherapy treatment plans using distal-edge tracking on both phantom and patient datasets.Results: Beam transport calculations show that a pair of electromagnetic quadrupoles can be used to create a divergent fan beam of 200 MeV protons over a distance of 2.1 m. The quadrupole lengths were 30 and 48 cm, respectively, with transverse field gradients less than 20 T/m, which is within the range of water-cooled magnets for the quadrupole radii used. MCNPX simulations of topotherapy treatment plans suggest that, when using the distal edge tracking delivery method, many delivery angles are more important than insisting on narrow beam channel widths in order to obtain conformal target coverage. Overall, the sharp distal falloff of a proton depth-dose distribution was found to provide sufficient control over the dose distribution to meet objectives, even with coarse lateral resolution and channel widths as large as 2 cm. Treatment plans on both phantom and patient data show that dose conformity suffers when treatments are delivered from less than approximately ten angles. Treatment time for a sample prostate delivery is estimated to be on the order of 10 min, and neutron production is estimated to be comparable to that found for existing collimated systems.Conclusions: Fan beam proton therapy is a method of delivering intensity modulated proton therapy which may be employed as an alternative to magnetic scanning systems. A fan beam of protons can be created by a set of quadrupole magnets and modified by a dual-purpose range and intensity modulator. This can be used to deliver inversely planned treatments, with spot intensities optimized to meet user defined dose objectives. Additionally, the ability of a fan beam delivery system to effectively treat multiple beam spots simultaneously may provide advantages as compared to spot scanning deliveries.

  17. The Path a Proton Takes Through a Fuel Cell Membrane

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

    Path a Proton Takes Through a Fuel Cell Membrane The Path a Proton Takes Through a Fuel Cell Membrane October 11, 2012 | Tags: Basic Energy Sciences (BES), Chemistry, Franklin,...

  18. Small Business Innovation Research Award Success Story: Proton Energy Systems

    Fuel Cell Technologies Publication and Product Library (EERE)

    This success story describes Proton Energy Systems, a small business that designs and manufactures proton exchange membrane (PEM) electrolysis sytems to produce hydrogen from water. The U.S. Departmen

  19. Minimal Proton Channel Enables H2 Oxidation and Production with...

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

    Minimal Proton Channel Enables H2 Oxidation and Production with a Water-Soluble Nickel-Based Catalyst. Minimal Proton Channel Enables H2 Oxidation and Production with a...

  20. AB Proton NMR Using Tensor Algebra Frank Rioux

    E-Print Network [OSTI]

    Rioux, Frank

    AB Proton NMR Using Tensor Algebra Frank Rioux Professor Emeritus of Chemistry CSB|SJU The purpose of this tutorial is to deviate from the usual matrix mechanics approach to the ABC proton nmr system in order

  1. amide proton resonances: Topics by E-print Network

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

    (IHRP funded by NHMFL) Citation: Da Wang, Kerim Gulyuz, Corey N 8 Exclusive ? production in proton-proton collisions in the resonance model Nuclear Theory (arXiv) Summary:...

  2. DYNAMIC MODELING PROTON EXCHANGE MEMBRANE FUEL CELL

    E-Print Network [OSTI]

    Mease, Kenneth D.

    DYNAMIC MODELING PROTON EXCHANGE MEMBRANE FUEL CELL OVERVIEW Current/Completed Plug Power to garner SCAQMD funding for fuel cell testing GenCore system is sensitive to diluents · As built design stream to compensate for removal of EGR · Functionality of the modified GenCore Fuel Cell system

  3. Proton recoil scintillator neutron rem meter

    DOE Patents [OSTI]

    Olsher, Richard H. (Los Alamos, NM); Seagraves, David T. (Los Alamos, NM)

    2003-01-01T23:59:59.000Z

    A neutron rem meter utilizing proton recoil and thermal neutron scintillators to provide neutron detection and dose measurement. In using both fast scintillators and a thermal neutron scintillator the meter provides a wide range of sensitivity, uniform directional response, and uniform dose response. The scintillators output light to a photomultiplier tube that produces an electrical signal to an external neutron counter.

  4. Proton Assisted Recoupling at High Spinning Frequencies

    E-Print Network [OSTI]

    Struppe, Jochem

    We demonstrate the successful application of [superscript 13]C?[superscript 13]C proton assisted recoupling (PAR) on [U?[superscript 13]C,[superscript 15]N] N-f-MLF-OH and [U?13C,15N] protein GB1 at high magic angle spinning ...

  5. PROTON RADIOGRAPHY FOR AN ADVANCED HYDROTEST FACILITY

    SciTech Connect (OSTI)

    C. MORRIS

    2000-11-01T23:59:59.000Z

    Analysis of data from BNL experiment 933 is presented. Results demonstrate that proton radiography can meet many of the requirements for an Advanced Hydrotest Facility (AHF). Results for background, position resolution, metrology, quantitative radiography, material identification, and edge resolution are presented.

  6. Field emission chemical sensor

    DOE Patents [OSTI]

    Panitz, J.A.

    1983-11-22T23:59:59.000Z

    A field emission chemical sensor for specific detection of a chemical entity in a sample includes a closed chamber enclosing two field emission electrode sets, each field emission electrode set comprising (a) an electron emitter electrode from which field emission electrons can be emitted when an effective voltage is connected to the electrode set; and (b) a collector electrode which will capture said electrons emitted from said emitter electrode. One of the electrode sets is passive to the chemical entity and the other is active thereto and has an active emitter electrode which will bind the chemical entity when contacted therewith.

  7. Modeling Traffic Flow Emissions

    E-Print Network [OSTI]

    Cappiello, Alessandra

    2002-09-17T23:59:59.000Z

    The main topic of this thesis is the development of light-duty vehicle dynamic emission models and their integration with dynamic traffic models. Combined, these models

  8. Saving Fuel, Reducing Emissions

    E-Print Network [OSTI]

    Kammen, Daniel M.; Arons, Samuel M.; Lemoine, Derek M.; Hummel, Holmes

    2009-01-01T23:59:59.000Z

    would in turn lower PHEV fuel costs and make them morestretches from fossil-fuel- powered conventional vehiclesbraking, as do Saving Fuel, Reducing Emissions Making Plug-

  9. Vehicle Emissions Review - 2011

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

    mass, membrane effects, fundamentals on permeability * DOC Pd:Pt ratios allow optimization * Gasoline emission control is amazing - Zone coating - Lower PGM with better...

  10. Cross sections for pentaquark baryon production from protons in reactions induced by hadrons and photons

    E-Print Network [OSTI]

    Liu, W.; Ko, Che Ming.

    2003-01-01T23:59:59.000Z

    Using hadronic Lagrangians that include the interaction of pentaquark Theta(+) baryon with K and N, we evaluate the cross sections for its production from meson-proton, proton-proton, and photon-proton reactions near threshold.,With empirical...

  11. Measurement of the analysing power in proton-proton elastic scattering at small angles

    E-Print Network [OSTI]

    Z. Bagdasarian; D. Chiladze; S. Dymov; A. Kacharava; G. Macharashvili; S. Barsov; R. Gebel; B. Gou; M. Hartmann; I. Keshelashvili; A. Khoukaz; P. Kulessa; A. Kulikov; A. Lehrach; N. Lomidze; B. Lorentz; R. Maier; D. Mchedlishvili; S. Merzliakov; S. Mikirtychyants; M. Nioradze; H. Ohm; M. Papenbrock; D. Prasuhn; F. Rathmann; V. Serdyuk; V. Shmakova; R. Stassen; H. Stockhorst; I. I. Strakovsky; H. Ströher; M. Tabidze; A. Täschner; S. Trusov; D. Tsirkov; Yu. Uzikov; Yu. Valdau; C. Wilkin; R. L. Workman

    2014-10-28T23:59:59.000Z

    The proton analysing power in $\\vec{p}p$ elastic scattering has been measured at small angles at COSY-ANKE at 796 MeV and five other beam energies between 1.6 and 2.4 GeV using a polarised proton beam. The asymmetries obtained by detecting the fast proton in the ANKE forward detector or the slow recoil proton in a silicon tracking telescope are completely consistent. Although the analysing power results agree well with the many published data at 796 MeV, and also with the most recent partial wave solution at this energy, the ANKE data at the higher energies lie well above the predictions of this solution at small angles. An updated phase shift analysis that uses the ANKE results together with the World data leads to a much better description of these new measurements.

  12. Jet measurements in proton-proton collisions with the ALICE experiment at LHC

    E-Print Network [OSTI]

    Michal Vajzer

    2013-01-13T23:59:59.000Z

    The study of jets, collimated sprays of particles associated with hard partons, is an important tool in testing perturbative quantum chromodynamics (pQCD) and probing hot and dense nuclear matter created in high energy heavy-ion collisions. Jets enable the study of hard scatterings, fragmentation and hadronisation and their modification in the presence of a nuclear medium with respect to baseline vacuum measurements, which is acquired from jet measurements in proton-proton collisions. We have analysed data from proton-proton collisions at s= \\sqrt{s} = 7 TeV measured by the ALICE experiment at the LHC and reconstructed the inclusive spectra of charged particle jets at mid- rapidity using anti-kT clustering algorithm. We present the jet spectra corrected for detector effects using several unfolding methods. Furthermore, we examine various properties of jets, such as their charged particle multiplicity and jet shapes.

  13. Investigation of proton focusing and conversion efficiency for proton fast ignition

    E-Print Network [OSTI]

    Bartal, Teresa Jean

    2012-01-01T23:59:59.000Z

    Protons from Ultra-short Pulse Laser Irradiated Foils. PhD2 [9]. The short ultra intense laser will generate particleswith a short (1- 10 ps) ultra intense laser (? 10 19 Wcm ?

  14. anti-proton proton annihilation: Topics by E-print Network

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

    24 25 Next Page Last Page Topic Index 1 Anti-proton and positron Cosmic Rays from Dark Matter annihilation around Intermediate Mass Black Holes Astrophysics (arXiv) Summary:...

  15. Observation of O++++ 4 lines in proton aurora over Svalbard

    E-Print Network [OSTI]

    Lummerzheim, Dirk

    Observation of O++++ 4 P-4 D0 lines in proton aurora over Svalbard N. Ivchenko,1,2 M. Galand,3 B. S March 2004; accepted 26 March 2004; published 29 May 2004. [1] Spectra of a proton aurora event show electron aurora. Conjugate satellite particle measurements are used as input to electron and proton

  16. Spectral imaging of proton aurora and twilight at Troms, Norway

    E-Print Network [OSTI]

    Lummerzheim, Dirk

    Spectral imaging of proton aurora and twilight at Tromsø, Norway M. Galand,1 J. Baumgardner,1 D, which offers a unique opportunity to investigate the Ha to Hb Balmer decrement in proton aurora locations (Tromsø, Poker Flat, Svalbard) in proton aurora is presented. Lummerzheim and Galand [2001] find

  17. Electron and proton aurora observed spectroscopically in the far ultraviolet

    E-Print Network [OSTI]

    Lummerzheim, Dirk

    Electron and proton aurora observed spectroscopically in the far ultraviolet M. Galand,1 D the location of the electron and proton aurorae is discussed. The estimation of the particle characteristics aurora. Because protons and electrons do not interact in the same way with the atmosphere, our study

  18. Investigation of Transient Phenomena of Proton Exchange Membrane Fuel Cells

    E-Print Network [OSTI]

    Victoria, University of

    Investigation of Transient Phenomena of Proton Exchange Membrane Fuel Cells by Roongrojana of Proton Exchange Membrane Fuel Cells by Roongrojana Songprakorp BSc, Prince of Songkhla University to the modeling and under- standing of the dynamic behavior of proton exchange membrane fuel cells (PEMFCs

  19. Proton Transfer and Hydrogen Bonding in Chemical and Biological

    E-Print Network [OSTI]

    Amrhein, Valentin

    Proton Transfer and Hydrogen Bonding in Chemical and Biological Systems: A Force Field Approach and support. i #12;ii #12;Abstract Proton transfer and hydrogen bonds are fundamental for the function be regarded as incipient proton transfer reactions, so theoretically they can be de- scribed in unitary way

  20. AB3 Proton NMR Using Tensor Algebra Frank Rioux

    E-Print Network [OSTI]

    Rioux, Frank

    AB3 Proton NMR Using Tensor Algebra Frank Rioux Professor Emeritus of Chemistry CSB|SJU The purpose of this tutorial is to calculate the NMR spectrum of a four proton AB3 system in Hz) are for the AB3 proton system 1,1dichloroethane at 60 MHz. A 350.0 B 120.0 Jab 10.00 Hamiltonian

  1. Proton corebeam system in the expanding solar wind: Hybrid simulations

    E-Print Network [OSTI]

    California at Berkeley, University of

    Proton corebeam system in the expanding solar wind: Hybrid simulations Petr Hellinger1,2 and Pavel 9 November 2011. [1] Results of a twodimensional hybrid expanding box simulation of a proton to a decrease of the ratio between the proton perpendicular and parallel temperatures as well as to an increase

  2. Tertiary proton diagnostics in future inertial confinement fusion experiments

    E-Print Network [OSTI]

    Tertiary proton diagnostics in future inertial confinement fusion experiments S. Cremera) and C. P energetic up to 31 MeV tertiary protons produced during the final stage of inertial confinement fusion the elastic scattering of 14.1 MeV neutrons, is a source of very energetic protons capable of escaping from

  3. Proton aurora related to intervals of pulsations of diminishing periods

    E-Print Network [OSTI]

    California at Berkeley, University of

    Proton aurora related to intervals of pulsations of diminishing periods A. G. Yahnin,1 T. A are generated because of a cyclotron instability of the anisotropic distribution of ring current ions. Proton precipitation produced by the cyclotron instability can be responsible for proton aurora. Indeed

  4. PROTON: A Prolog Reasoner for Temporal ONtologies Nikos Papadakis1

    E-Print Network [OSTI]

    Petrakis, Euripides G.M.

    PROTON: A Prolog Reasoner for Temporal ONtologies in OWL Nikos Papadakis1 ,Kostas Stravoskoufos2, University of Crete, dp@csd.uoc.gr Abstract We present PROTON, a reasoner for managing temporal information. PROTON is implemented using this extension. Key words: Ramification problem; Temporal Ontologies

  5. UNIVERSITY OF CALIFORNIA PRELIMINARY TRACKING STUDIES FOR PROTON

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    UNIVERSITY OF CALIFORNIA SANTA CRUZ PRELIMINARY TRACKING STUDIES FOR PROTON COMPUTED TOMOGRAPHY Acknowledgments xi 1 Introduction 1 1.1 The Need for Proton Computed Tomography . . . . . . . . . . . . . . . 1 1 Limitations . . . . . . . . . . . . . . . . . 7 1.4 Treatment Planning: Proton CT vs. X-ray CT

  6. Nanoscale Current Imaging of the Conducting Channels in Proton

    E-Print Network [OSTI]

    Buratto, Steve

    Nanoscale Current Imaging of the Conducting Channels in Proton Exchange Membrane Fuel Cells David A area of a proton exchange membrane fuel cell (PEMFC) is investigated using conductive probe atomic particle at its end. This is due to the formation of protons, at the carbon cloth side of the cell

  7. Proton Computed Tomography and Constructing Tracker Boards Gatlin Bredeson

    E-Print Network [OSTI]

    Belanger, David P.

    1 ABSTRACT Proton Computed Tomography and Constructing Tracker Boards By Gatlin Bredeson Scientists tomography (xCT) with proton computed tomography (pCT). During a CT scan, protons pass through a phantom University to build tracker boards to assist in creating a system that seeks to replace X-ray computed

  8. Observation of solar high energy gamma and X-ray emission and solar energetic particles

    E-Print Network [OSTI]

    Struminsky, Alexei

    2015-01-01T23:59:59.000Z

    We considered 18 solar flares observed between June 2010 and July 2012, in which high energy >100 MeV {\\gamma}-emission was registered by the Large Area Telescope (LAT) aboard FermiGRO. We examined for these {\\gamma}-events soft X-ray observations by GOES, hard X-ray observations by the Anti-Coincidence Shield of the SPectrometer aboard INTEGRAL (ACS SPI) and the Gamma-Ray burst Monitor (GBM) aboard FermiGRO. Hard X-ray and {\\pi}0-decay {\\gamma}-ray emissions are used as tracers of electron and proton acceleration, respectively. Bursts of hard X-ray were observed by ACS SPI during impulsive phase of 13 events. Bursts of hard X-ray >100 keV were not found during time intervals, when prolonged hard {\\gamma}-emission was registered by LAT/FermiGRO. Those events showing prolonged high-energy gamma-ray emission not accompanied by >100 keV hard X-ray emission are interpreted as an indication of either different acceleration processes for protons and electrons or as the presence of a proton population accelerated du...

  9. Air Emission Inventory for the INEEL -- 1999 Emission Report

    SciTech Connect (OSTI)

    Zohner, Steven K

    2000-05-01T23:59:59.000Z

    This report presents the 1999 calendar year update of the Air Emission Inventory for the Idaho National Engineering and Environmental Laboratory (INEEL). The INEEL Air Emission Inventory documents sources and emissions of nonradionuclide pollutants from operations at the INEEL. The report describes the emission inventory process and all of the sources at the INEEL, and provides nonradionuclide emissions estimates for stationary sources.

  10. Exclusive photoproduction of J/psi and psi(2S) states in proton-proton collisions at the CERN LHC

    E-Print Network [OSTI]

    M. B. Gay Ducati; M. T. Griep; M. V. T. Machado

    2014-06-18T23:59:59.000Z

    In this work we investigate the exclusive photoproduction of J/psi and the radially excited psi(2S) state off nucleon in proton-proton collisions. The theoretical framework considered in the analysis is the light-cone dipole formalism and predictions are done for proton-proton collisions at the CERN-LHC energy of 7 TeV. The theoretical uncertainties are investigated and comparison is done to the recent LHCb Collaboration data for the exclusive charmonium production.

  11. Cosmic recycling of millisecond pulsars

    E-Print Network [OSTI]

    Wynn C. G. Ho; Thomas J. Maccarone; Nils Andersson

    2011-04-07T23:59:59.000Z

    We compare the rotation rate of neutron stars in low-mass X-ray binaries (LMXBs) with the orbital period of the binaries. We find that, while short orbital period LMXBs span a range of neutron star rotation rates, all the long period LMXBs have fast rotators. We also find that the rotation rates are highest for the systems with the highest mean mass accretion rates, as can be expected if the accretion rate correlates with the orbital period. We show that these properties can be understood by a balance between spin-up due to accretion and spin-down due to gravitational radiation. Our scenario indicates that the gravitational radiation emitted by these systems may be detectable by future ground-based gravitational wave detectors.

  12. Graphene field emission devices

    SciTech Connect (OSTI)

    Kumar, S., E-mail: shishirk@gmail.com; Raghavan, S. [Centre for Nanoscience and Engineering, Indian Institute of Science, Bengaluru (India); Duesberg, G. S. [Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN) and School of Chemistry, Trinity College Dublin, Dublin, D2 (Ireland); Pratap, R. [Centre for Nanoscience and Engineering, Indian Institute of Science, Bengaluru (India); Department of Mechanical Engineering, Indian Institute of Science, Bengaluru (India)

    2014-09-08T23:59:59.000Z

    Graphene field emission devices are fabricated using a scalable process. The field enhancement factors, determined from the Fowler-Nordheim plots, are within few hundreds and match the theoretical predictions. The devices show high emission current density of ?10?nA ?m{sup ?1} at modest voltages of tens of volts. The emission is stable with time and repeatable over long term, whereas the noise in the emission current is comparable to that from individual carbon nanotubes emitting under similar conditions. We demonstrate a power law dependence of emission current on pressure which can be utilized for sensing. The excellent characteristics and relative ease of making the devices promise their great potential for sensing and electronic applications.

  13. Leading proton production in deep inelastic scattering at HERA

    E-Print Network [OSTI]

    ZEUS Collaboration

    2008-12-12T23:59:59.000Z

    The semi-inclusive reaction e+ p -> e+ X p was studied with the ZEUS detector at HERA using an integrated luminosity of 12.8 pb-1. The final-state proton, which was detected with the ZEUS leading proton spectrometer, carried a large fraction of the incoming proton energy, xL>0.32, and its transverse momentum squared satisfied pT^2proton system was 45proton production cross section and rates are presented as a function of xL, pT^2, Q^2 and the Bjorken scaling variable, x.

  14. Recoil proton distribution in high energy photoproduction processes

    E-Print Network [OSTI]

    E. Bartos; E. A. Kuraev; Yu. P. Peresunko; E. A. Vinokurov

    2006-11-22T23:59:59.000Z

    For high energy linearly polarized photon--proton scattering we have calculated the azimuthal and polar angle distributions in inclusive on recoil proton experimental setup. We have taken into account the production of lepton and pseudoscalar meson charged pairs. The typical values of cross sections are of order of hundreds of picobarn. The size of polarization effects are of order of several percents. The results are generalized for the case of electroproduction processes on the proton at rest and for high energy proton production process on resting proton.

  15. Kinetics of proton pumping in cytochrome c oxidase

    E-Print Network [OSTI]

    Anatoly Yu. Smirnov; Lev G. Mourokh; Franco Nori

    2009-12-04T23:59:59.000Z

    We propose a simple model of cytochrome c oxidase, including four redox centers and four protonable sites, to study the time evolution of electrostatically coupled electron and proton transfers initiated by the injection of a single electron into the enzyme. We derive a system of master equations for electron and proton state probabilities and show that an efficient pumping of protons across the membrane can be obtained for a reasonable set of parameters. All four experimentally observed kinetic phases appear naturally from our model. We also calculate the dependence of the pumping efficiency on the transmembrane voltage at different temperatures and discuss a possible mechanism of the redox-driven proton translocation.

  16. The quest for cosmic ray protons in galaxy clusters

    E-Print Network [OSTI]

    Christoph Pfrommer; Torsten A. Ensslin

    2004-12-15T23:59:59.000Z

    There have been many speculations about the presence of cosmic ray protons (CRps) in galaxy clusters over the past two decades. However, no direct evidence such as the characteristic gamma-ray signature of decaying pions has been found so far. These pions would be a direct tracer of hadronic CRp interactions with the ambient thermal gas also yielding observable synchrotron and inverse Compton emission by additionally produced secondary electrons. The obvious question concerns the type of galaxy clusters most likely to yield a signal: Particularly suited sites should be cluster cooling cores due to their high gas and magnetic energy densities. We studied a nearby sample of clusters evincing cooling cores in order to place stringent limits on the cluster CRp population by using non-detections of EGRET. In this context, we examined the possibility of a hadronic origin of Coma-sized radio halos as well as radio mini-halos. Especially for mini-halos, strong clues are provided by the very plausible small amount of required CRp energy density and a matching radio profile. Introducing the hadronic minimum energy criterion, we show that the energetically favored CRp energy density is constrained to 2% +/- 1% of the thermal energy density in Perseus. We also studied the CRp population within the cooling core region of Virgo using the TeV gamma-ray detection of M 87 by HEGRA. Both the expected radial gamma-ray profile and the required amount of CRp support this hadronic scenario.

  17. Shuttle-mediated proton pumping across the inner mitochondrial membrane

    E-Print Network [OSTI]

    Smirnov, Anatoly Yu; Nori, Franco

    2008-01-01T23:59:59.000Z

    Shuttle-assisted charge transfer is pivotal for the efficient energy transduction from the food-stuff electrons to protons in the respiratory chain of animal cells and bacteria. The respiratory chain consists of four metalloprotein Complexes (I-IV) embedded in the inner membrane of a mitochondrion. Three of these complexes pump protons across the membrane, fuelled by the energy of food-stuff electrons. Despite extensive biochemical and biophysical studies, the physical mechanism of this proton pumping is still not well understood. Here we present a nanoelectromechanical model of the electron-driven proton pump related to the second loop of the respiratory chain, where a lipid-soluble ubiquinone molecule shuttles between the Complex I and Complex III, carrying two electrons and two protons. We show that the energy of electrons can be converted to the transmembrane proton potential gradient via the electrostatic interaction between electrons and protons on the shuttle. We find that the system can operate either...

  18. Forster mechanism of electron-driven proton pump

    E-Print Network [OSTI]

    Anatoly Yu. Smirnov; Lev G. Mourokh; Franco Nori

    2007-11-08T23:59:59.000Z

    We examine a simple model of proton pumping through the inner membrane of mitochondria in the living cell. We demonstrate that the pumping process can be described using approaches of condensed matter physics. In the framework of this model, we show that the resonant F\\"orster-type energy exchange due to electron-proton Coulomb interaction can provide an unidirectional flow of protons against an electrochemical proton gradient, thereby accomplishing proton pumping. The dependence of this effect on temperature as well as electron and proton voltage build-ups are obtained taking into account electrostatic forces and noise in the environment. We find that the proton pump works with maximum efficiency in the range of temperatures and transmembrane electrochemical potentials which correspond to the parameters of living cells.

  19. Properties of solar energetic particle events inferred from their associated radio emission

    E-Print Network [OSTI]

    Kouloumvakos, A; Valtonen, E; Alissandrakis, C E; Malandraki, O; Tsitsipis, P; Kontogeorgos, A; Moussas, X; Hillaris, A

    2015-01-01T23:59:59.000Z

    We study selected properties of Solar Energetic Particle (SEP) events as inferred from their associated radio emissions. We used a catalogue of 115 SEP events that consists of entries of proton intensity enhancements at one AU, with complete coverage over solar cycle 23, based on high-energy (~68 MeV) protons from SOHO/ERNE and we calculated the proton release time at the Sun using velocity dispersion analysis (VDA). After an initial rejection of cases with unrealistic VDA path lengths, we assembled composite radio spectra for the remaining events using data from ground-based and space-borne radio-spectrographs. For every event we registered the associated radio emissions and we divided the events in groups according to their associated radio emissions. The proton release was found to be most often accompanied by both type III and II radio bursts, but a good association percentage was also registered in cases accompanied by type IIIs only. The worst association was found for the cases with type II only associ...

  20. Spontaneous Emission Rate Enhancement Using Optical Antennas

    E-Print Network [OSTI]

    Kumar, Nikhil

    2013-01-01T23:59:59.000Z

    of  Spontaneous  Emission  in  a  Semiconductor  nanoLED,”  emission  rate  enhancement  using  the  Fluorescent  Emission  by  Lattice   Resonances  in  

  1. EMISSION AND TRANSMISSION NOISE PROPAGATION IN POSITRON EMISSION COMPUTED TOMOGRAPHY

    E-Print Network [OSTI]

    Gullberg, G.T.

    2010-01-01T23:59:59.000Z

    High Resolution Computed Tomography of Positron Emitters,"of Dynamic Emission Computed Tomography," J. Nucl. Med. ~:IN POSITRON EMISSION COMPUTED TOMOGRAPHY RECEIVED lAWRENCE

  2. Contraction & Convergence: UK carbon emissions and the

    E-Print Network [OSTI]

    Watson, Andrew

    the EU's emissions trading scheme will do little to mitigate carbon emissions 4) Aviation growth must emissions. Keywords Contraction & Convergence; aviation; emissions trading; passengers; carbon dioxide #12

  3. Parity Violation in gamma proton Compton Scattering

    E-Print Network [OSTI]

    Paulo F. Bedaque; Martin J. Savage

    1999-10-19T23:59:59.000Z

    A measurement of parity-violating spin-dependent gamma proton Compton scattering will provide a theoretically clean determination of the parity-violating pion-nucleon coupling constant $h_{\\pi NN}^{(1)}$. We calculate the leading parity-violating amplitude arising from one-loop pion graphs in chiral perturbation theory. An asymmetry of ~5 10^{-8} is estimated for Compton scattering of 100 MeV photons.

  4. Method of synthesis of proton conducting materials

    DOE Patents [OSTI]

    Garzon, Fernando Henry; Einsla, Melinda Lou; Mukundan, Rangachary

    2010-06-15T23:59:59.000Z

    A method of producing a proton conducting material, comprising adding a pyrophosphate salt to a solvent to produce a dissolved pyrophosphate salt; adding an inorganic acid salt to a solvent to produce a dissolved inorganic acid salt; adding the dissolved inorganic acid salt to the dissolved pyrophosphate salt to produce a mixture; substantially evaporating the solvent from the mixture to produce a precipitate; and calcining the precipitate at a temperature of from about 400.degree. C. to about 1200.degree. C.

  5. Pion-proton correlations and asymmetry measurement in Au+Au collisions at $\\sqrt{s_{NN}}=200$ $GeV$ data

    E-Print Network [OSTI]

    Marcin Zawisza; for the STAR Collaboration

    2010-12-30T23:59:59.000Z

    Correlations between non-identical particles at small relative velocity probe asymmetries in the average space-time emission points at freeze-out. The origin of such asymmetries may be from long-lived resonances, bulk collective effects, or differences in the freeze-out scenario for the different particle species. STAR has extracted pion-proton correlation functions from a dataset of Au+Au collisions at $\\sqrt{s_{NN}}=200$ $GeV$. We present correlation functions in the spherical harmonic decomposition representation, for different centralities and for different combinations of pions and (anti-)protons.

  6. Proton Irradiation Study of GFR Candidate Ceramics

    SciTech Connect (OSTI)

    Jian Gan; Yong Yang; Clayton Dickson; Todd Allen

    2009-05-01T23:59:59.000Z

    This work investigated the microstructural response of ZrC, ZrN, TiN, and SiC irradiated with 2.6 MeV protons at 800ºC to a single dose in the range of 1.5 to 3.0 displacement per atom (dpa), depending on the material. The change of lattice constant evaluated using HOLZ patterns is not observed and is small when measured using XRD for the irradiated samples up to 1.5 dpa for 6H-SiC, and up to 3.0 dpa for ZrC and ZrN. In comparison to Kr ion irradiation at 800ºC to 10 dpa from the previous studies, the proton-irradiated ceramics at 3.0 dpa show less irradiation damage to the lattice structure. The irradiated ZrC exhibits faulted loops which are not observed in the Kr ion irradiated sample. The irradiated ZrN shows the least microstructural change from proton irradiation. The microstructure of 6H-SiC irradiated to 3.0 dpa consists of a black dot defect type at high density.

  7. FFAG ACCELERATOR PROTON DRIVER FOR NEUTRINO FACTORY.

    SciTech Connect (OSTI)

    RUGGIERO, A.

    2005-06-21T23:59:59.000Z

    This paper is the summary of a conceptual study of a Proton Driver for Neutrino Factory based on the use of a Fixed-Field Alternating-Gradient (FFAG) Accelerator. The required proton energy range for an optimum neutrino production is 5 to 12 GeV. This can be accomplished with a group of three concentric rings each with 807 m circumference [1]. FFAG Accelerators [2] have the capability to accelerate charged particles over a large momentum range ({+-}30-50%) and the feature of constant bending and focusing fields. Particles can be accelerated very fast at the rate given by the accelerating field of RF cavities placed in proper locations between magnets. The performance of FFAG accelerators is to be placed between that of Super-Conducting Linear Accelerators (SCL), with which they share the fast acceleration rate, and Rapid-Cycling Synchrotrons (RCS), as they allow the beam to re-circulate over fewer revolutions. Brookhaven National Laboratory is involved in the study of feasibility of FFAG Accelerators to accelerate intense beams of protons in the GeV energy range for a variety of applications the most important of which is the Upgrade of the Alternating Gradient Synchrotron (AGS) with a new FFAG injector [3] accelerating from 400 MeV to 1.5 GeV. The ring would be housed in the AGS tunnel and has henceforth a circumference of 807 m.

  8. Emission Abatement System

    DOE Patents [OSTI]

    Bromberg, Leslie (Sharon, MA); Cohn, Daniel R. (Chestnut Hill, MA); Rabinovich, Alexander (Swampscott, MA)

    2003-05-13T23:59:59.000Z

    Emission abatement system. The system includes a source of emissions and a catalyst for receiving the emissions. Suitable catalysts are absorber catalysts and selective catalytic reduction catalysts. A plasma fuel converter generates a reducing gas from a fuel source and is connected to deliver the reducing gas into contact with the absorber catalyst for regenerating the catalyst. A preferred reducing gas is a hydrogen rich gas and a preferred plasma fuel converter is a plasmatron. It is also preferred that the absorber catalyst be adapted for absorbing NO.sub.x.

  9. Generalized z-scaling in proton-proton collisions at high energies

    E-Print Network [OSTI]

    I. Zborovsky; M. Tokarev

    2006-03-28T23:59:59.000Z

    New generalization of z-scaling in inclusive particle production is proposed. The scaling variable z is fractal measure which depends on kinematical characteristics of the underlying sub-process expressed in terms of the momentum fractions x1 and x2 of the incoming protons. In the generalized approach, the x1 and x2 are functions of the momentum fractions ya and yb of the scattered and recoil constituents carried out by the inclusive particle and recoil object, respectively. The scaling function psi(z) for charged and identified hadrons produced in proton-proton collisions is constructed. The fractal dimensions and heat capacity of the produced medium entering definition of the z are established to obtain energy, angular and multiplicity independence of the psi(z). The scheme allows unique description of data on inclusive cross sections of charged particles, pions, kaons, antiprotons and lambdas at high energies. The obtained results are of interest to use z-scaling as a tool for searching for new physics phenomena of particle production in high transverse momentum and high multiplicity region at proton-proton colliders RHIC and LHC.

  10. Reconstruction for proton computed tomography by tracing proton trajectories: A Monte Carlo study

    SciTech Connect (OSTI)

    Li Tianfang; Liang Zhengrong; Singanallur, Jayalakshmi V.; Satogata, Todd J.; Williams, David C.; Schulte, Reinhard W. [Departments of Radiology, Computer Science, and Physics and Astronomy, State University of New York at Stony Brook, Stony Brook, New York 11794 (United States); Department of Physics, Brookhaven National Laboratory, Upton, New York 11973 (United States); Santa Cruz Institute for Particle Physics, University of California at Santa Cruz, Santa Cruz, California 95064 (United States); Department of Radiation Medicine, Loma Linda University Medical Center, Loma Linda, California 92354 (United States)

    2006-03-15T23:59:59.000Z

    Proton computed tomography (pCT) has been explored in the past decades because of its unique imaging characteristics, low radiation dose, and its possible use for treatment planning and on-line target localization in proton therapy. However, reconstruction of pCT images is challenging because the proton path within the object to be imaged is statistically affected by multiple Coulomb scattering. In this paper, we employ GEANT4-based Monte Carlo simulations of the two-dimensional pCT reconstruction of an elliptical phantom to investigate the possible use of the algebraic reconstruction technique (ART) with three different path-estimation methods for pCT reconstruction. The first method assumes a straight-line path (SLP) connecting the proton entry and exit positions, the second method adapts the most-likely path (MLP) theoretically determined for a uniform medium, and the third method employs a cubic spline path (CSP). The ART reconstructions showed progressive improvement of spatial resolution when going from the SLP [2 line pairs (lp) cm{sup -1}] to the curved CSP and MLP path estimates (5 lp cm{sup -1}). The MLP-based ART algorithm had the fastest convergence and smallest residual error of all three estimates. This work demonstrates the advantage of tracking curved proton paths in conjunction with the ART algorithm and curved path estimates.

  11. Emission Standards for Contaminants (Iowa)

    Broader source: Energy.gov [DOE]

    These regulations list emissions standards for various contaminants, and contain special requirements for anaerobic lagoons. These regulations also describe alternative emissions limits, which may...

  12. Measurement of Transverse Single Spin Asymmetries for $\\pi^{0}$ and Jets at Large $x_{F}$ in $\\sqrt{s}$ = 500 GeV Polarized Proton Collisions at STAR

    E-Print Network [OSTI]

    Pan, Yuxi

    2015-01-01T23:59:59.000Z

    Proton . . . . . . . . . . . . . . . . . . . . . . . . . . . . .as a polarized proton collider . . . . . . . . . . . . .Proton (p) as in the Baryon-Octet

  13. Greenhouse Gas Emissions (Minnesota)

    Broader source: Energy.gov [DOE]

    This statute sets goals for the reduction of statewide greenhouse gas emissions by at least 15 percent by 2015, 30 percent by 2025, and 80 percent by 2050, calculated relative to 2005 levels. These...

  14. Photon enhanced thermionic emission

    DOE Patents [OSTI]

    Schwede, Jared; Melosh, Nicholas; Shen, Zhixun

    2014-10-07T23:59:59.000Z

    Photon Enhanced Thermionic Emission (PETE) is exploited to provide improved efficiency for radiant energy conversion. A hot (greater than 200.degree. C.) semiconductor cathode is illuminated such that it emits electrons. Because the cathode is hot, significantly more electrons are emitted than would be emitted from a room temperature (or colder) cathode under the same illumination conditions. As a result of this increased electron emission, the energy conversion efficiency can be significantly increased relative to a conventional photovoltaic device. In PETE, the cathode electrons can be (and typically are) thermalized with respect to the cathode. As a result, PETE does not rely on emission of non-thermalized electrons, and is significantly easier to implement than hot-carrier emission approaches.

  15. Field emission electron source

    DOE Patents [OSTI]

    Zettl, Alexander Karlwalter (Kensington, CA); Cohen, Marvin Lou (Berkeley, CA)

    2000-01-01T23:59:59.000Z

    A novel field emitter material, field emission electron source, and commercially feasible fabrication method is described. The inventive field emission electron source produces reliable electron currents of up to 400 mA/cm.sup.2 at 200 volts. The emitter is robust and the current it produces is not sensitive to variability of vacuum or the distance between the emitter tip and the cathode. The novel emitter has a sharp turn-on near 100 volts.

  16. Wildland fire emissions, carbon, and climate: Emission factors Shawn Urbanski

    E-Print Network [OSTI]

    Wildland fire emissions, carbon, and climate: Emission factors Shawn Urbanski Missoula Fire burning Greenhouse gases Emission factors a b s t r a c t While the vast majority of carbon emitted mixture of gases and aerosols. Primary emissions include sig- nificant amounts of CH4 and aerosol (organic

  17. Nuclear like effects in proton-proton collisions at high energy

    E-Print Network [OSTI]

    L. Cunqueiro; J. Dias de Deus; C. Pajares

    2009-09-17T23:59:59.000Z

    We show that several effects considered nuclear effects are not nuclear in the sense that they do not only occur in nucleus-nucleus and hadron-nucleus collisions but, as well, they are present in hadron-hadron (proton-proton) collisions. The matter creation mechanism in hh, hA and AA collisions is always the same. The pT suppression of particles produced in large multiplicity events compared to low multiplicity events, the elliptic flow and the Cronin effect are predicted to occur in pp collisions at LHC energies as a consequence of the obtained high density partonic medium.

  18. Comprehensive description of J/? production in proton-proton collisions at collider energies

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

    Ma, Yan-Qing [Brookhaven National Laboratory (BNL), Upton, NY (United States); Venugopalan, Raju [Brookhaven National Laboratory (BNL), Upton, NY (United States)

    2014-11-04T23:59:59.000Z

    We employ a small x Color Glass Condensate (CGC)+ Non-Relativistic QCD (NRQCD) formalism to compute J/ production at low p? in proton-proton collisions at collider energies. Very good agreement is obtained for total cross-sections, rapidity distributions and low momentum p? distributions. Similar agreement is obtained for production. We observe an overlap region in p? where our results match smoothly to those obtained in a next-to-leading order (NLO) collinearly factorized NRQCD formalism. The relative contribution of color singlet and color octet contributions can be quantified in the CGC+NRQCD framework, with the former contributing approximately 10% of the total cross-section.

  19. The Dependence of the Proton-Triton Nuclear Reaction Rate on the Temperature and Energy Content of the High-Energy Proton Distribution Function

    E-Print Network [OSTI]

    The Dependence of the Proton-Triton Nuclear Reaction Rate on the Temperature and Energy Content of the High-Energy Proton Distribution Function

  20. Search for physics beyond the standard model in final states with a lepton and missing transverse energy in proton-proton collisions at s = 8 TeV

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

    Khachatryan, V.; Sirunyan, A.?M.; Tumasyan, A.; Adam, W.; Bergauer, T.; Dragicevic, M.; Erö, J.; Fabjan, C.; Friedl, M.; Frühwirth, R.; Ghete, V.?M.; Hartl, C.; Hörmann, N.; Hrubec, J.; Jeitler, M.; Kiesenhofer, W.; Knünz, V.; Krammer, M.; Krätschmer, I.; Liko, D.; Mikulec, I.; Rabady, D.; Rahbaran, B.; Rohringer, H.; Schöfbeck, R.; Strauss, J.; Taurok, A.; Treberer-Treberspurg, W.; Waltenberger, W.; Wulz, C.-E.; Mossolov, V.; Shumeiko, N.; Suarez Gonzalez, J.; Alderweireldt, S.; Bansal, M.; Bansal, S.; Cornelis, T.; De Wolf, E.?A.; Janssen, X.; Knutsson, A.; Luyckx, S.; Ochesanu, S.; Roland, B.; Rougny, R.; Van De Klundert, M.; Van Haevermaet, H.; Van Mechelen, P.; Van Remortel, N.; Van Spilbeeck, A.; Blekman, F.; Blyweert, S.; D’Hondt, J.; Daci, N.; Heracleous, N.; Kalogeropoulos, A.; Keaveney, J.; Kim, T.?J.; Lowette, S.; Maes, M.; Olbrechts, A.; Python, Q.; Strom, D.; Tavernier, S.; Van Doninck, W.; Van Mulders, P.; Van Onsem, G.?P.; Villella, I.; Caillol, C.; Clerbaux, B.; De Lentdecker, G.; Dobur, D.; Favart, L.; Gay, A.?P.?R.; Grebenyuk, A.; Léonard, A.; Mohammadi, A.; Perniè, L.; Reis, T.; Seva, T.; Thomas, L.; Vander Velde, C.; Vanlaer, P.; Wang, J.; Adler, V.; Beernaert, K.; Benucci, L.; Cimmino, A.; Costantini, S.; Crucy, S.; Dildick, S.; Fagot, A.; Garcia, G.; Mccartin, J.; Ocampo Rios, A.?A.; Ryckbosch, D.; Salva Diblen, S.; Sigamani, M.; Strobbe, N.; Thyssen, F.; Tytgat, M.; Yazgan, E.; Zaganidis, N.; Basegmez, S.; Beluffi, C.; Bruno, G.; Castello, R.; Caudron, A.; Ceard, L.; Da Silveira, G.?G.; Delaere, C.; du Pree, T.; Favart, D.; Forthomme, L.; Giammanco, A.; Hollar, J.; Jez, P.; Komm, M.; Lemaitre, V.; Liao, J.; Nuttens, C.; Pagano, D.; Perrini, L.; Pin, A.; Piotrzkowski, K.; Popov, A.; Quertenmont, L.; Selvaggi, M.; Vidal Marono, M.; Vizan Garcia, J.?M.; Beliy, N.; Caebergs, T.; Daubie, E.; Hammad, G.?H.; Aldá Júnior, W.?L.; Alves, G.?A.; Correa Martins Junior, M.; Dos Reis Martins, T.; Pol, M.?E.; Carvalho, W.; Chinellato, J.; Custódio, A.; Da Costa, E.?M.; De Jesus Damiao, D.; De Oliveira Martins, C.; Fonseca De Souza, S.; Malbouisson, H.; Malek, M.; Matos Figueiredo, D.; Mundim, L.; Nogima, H.; Prado Da Silva, W.?L.; Santaolalla, J.; Santoro, A.; Sznajder, A.; Tonelli Manganote, E.?J.; Vilela Pereira, A.; Bernardes, C.?A.; Dias, F.?A.; Fernandez Perez Tomei, T.?R.; Gregores, E.?M.; Mercadante, P.?G.; Novaes, S.?F.; Padula, Sandra S.; Aleksandrov, A.; Genchev, V.; Iaydjiev, P.; Marinov, A.; Piperov, S.; Rodozov, M.; Sultanov, G.; Vutova, M.; Dimitrov, A.; Glushkov, I.; Hadjiiska, R.; Kozhuharov, V.; Litov, L.; Pavlov, B.; Petkov, P.; Bian, J.?G.; Chen, G.?M.; Chen, H.?S.; Chen, M.; Du, R.; Jiang, C.?H.; Liang, D.; Liang, S.; Plestina, R.; Tao, J.; Wang, X.; Wang, Z.; Asawatangtrakuldee, C.; Ban, Y.; Guo, Y.; Li, Q.; Li, W.; Liu, S.; Mao, Y.; Qian, S.?J.; Wang, D.; Zhang, L.; Zou, W.; Avila, C.; Chaparro Sierra, L.?F.; Florez, C.; Gomez, J.?P.; Gomez Moreno, B.; Sanabria, J.?C.; Godinovic, N.; Lelas, D.; Polic, D.; Puljak, I.; Antunovic, Z.; Kovac, M.; Brigljevic, V.; Kadija, K.; Luetic, J.; Mekterovic, D.; Sudic, L.; Attikis, A.; Mavromanolakis, G.; Mousa, J.; Nicolaou, C.; Ptochos, F.; Razis, P.?A.; Bodlak, M.; Finger, M.; Finger, M.; Assran, Y.; Elgammal, S.; Mahmoud, M.?A.; Radi, A.; Kadastik, M.; Murumaa, M.; Raidal, M.; Tiko, A.; Eerola, P.; Fedi, G.; Voutilainen, M.; Härkönen, J.; Karimäki, V.; Kinnunen, R.; Kortelainen, M.?J.; Lampén, T.; Lassila-Perini, K.; Lehti, S.; Lindén, T.; Luukka, P.; Mäenpää, T.; Peltola, T.; Tuominen, E.; Tuominiemi, J.; Tuovinen, E.; Wendland, L.; Tuuva, T.; Besancon, M.; Couderc, F.; Dejardin, M.; Denegri, D.; Fabbro, B.; Faure, J.?L.; Favaro, C.; Ferri, F.; Ganjour, S.; Givernaud, A.; Gras, P.; Hamel de Monchenault, G.; Jarry, P.; Locci, E.; Malcles, J.; Rander, J.; Rosowsky, A.; Titov, M.; Baffioni, S.; Beaudette, F.; Busson, P.; Charlot, C.; Dahms, T.; Dalchenko, M.; Dobrzynski, L.; Filipovic, N.; Florent, A.; Granier de Cassagnac, R.; Mastrolorenzo, L.; Miné, P.; Mironov, C.; Naranjo, I.?N.; Nguyen, M.; Ochando, C.; Paganini, P.; Salerno, R.; Sauvan, J.?B.; Sirois, Y.; Veelken, C.; Yilmaz, Y.; Zabi, A.; Agram, J.-L.; Andrea, J.; Aubin, A.; Bloch, D.; Brom, J.-M.; Chabert, E.?C.; Collard, C.; Conte, E.; Fontaine, J.-C.; Gelé, D.; Goerlach, U.; Goetzmann, C.; Le Bihan, A.-C.; Van Hove, P.; Gadrat, S.; Beauceron, S.; Beaupere, N.; Boudoul, G.; Brochet, S.; Carrillo Montoya, C.?A.; Chasserat, J.; Chierici, R.; Contardo, D.; Depasse, P.; El Mamouni, H.; Fan, J.; Fay, J.; Gascon, S.; Gouzevitch, M.; Ille, B.; Kurca, T.; Lethuillier, M.; Mirabito, L.; Perries, S.; Ruiz Alvarez, J.?D.; Sabes, D.; Sgandurra, L.

    2015-05-01T23:59:59.000Z

    A search for new physics in proton-proton collisions having final states with an electron or muon and missing transverse energy is presented.

  1. Green Fluorescent Protein Variants as Ratiometric Dual Emission pH Sensors. 2. Excited-State Dynamics

    E-Print Network [OSTI]

    Boxer, Steven G.

    of the high-energy absorption band centered at 398 nm and assigned to the neutral form of the chromophore-resolved emission dynamics and isotope effect appear to be very different from those of wild-type GFP [Chattoraj, M energy neutral chromophore to the lower energy intermediate anionic chromophore is achieved by proton

  2. Anti-Proton Evolution in Little Bangs and Big Bang

    E-Print Network [OSTI]

    H. Schade; B. Kampfer

    2009-03-30T23:59:59.000Z

    The abundances of anti-protons and protons are considered within momentum-integrated Boltzmann equations describing Little Bangs, i.e., fireballs created in relativistic heavy-ion collisions. Despite of a large anti-proton annihilation cross section we find a small drop of the ratio of anti-protons to protons from 170 MeV (chemical freeze-out temperature) till 100 MeV (kinetic freeze-out temperature) for CERN-SPS and BNL-RHIC energies thus corroborating the solution of the previously exposed "ani-proton puzzle". In contrast, the Big Bang evolves so slowly that the anti-baryons are kept for a long time in equilibrium resulting in an exceedingly small fraction. The adiabatic path of cosmic matter in the phase diagram of strongly interacting matter is mapped out.

  3. Antiproton-Proton Channels in J/psi Decays

    E-Print Network [OSTI]

    B. Loiseau; S. Wycech

    2005-12-16T23:59:59.000Z

    The recent measurements by the BES Collaboration of J/psi decays into a photon and a proton-antiproton pair indicate a strong enhancement at the proton-antiproton threshold not observed in the decays into a neutral pion and a proton-antiproton pair. Is this enhancement due to a proton-antiproton quasi-bound state or a baryonium? A natural explanation follows from a traditional model of proton-antiproton interactions based on G-parity transformation. The observed proton-antiproton structure is due to a strong attraction in the 1S0 state, and possibly to a near-threshold quasi-bound state in the 11S0 wave.

  4. Plans for a proton driver at Fermilab

    SciTech Connect (OSTI)

    Kephart, R.D.; /Fermilab

    2005-01-01T23:59:59.000Z

    During the last several years, stunning experimental results have established that neutrinos have nonzero masses and substantial mixing. The Standard Model must be extended to accommodate neutrino mass terms. The observation that neutrino masses and mass splittings are all many orders of magnitude smaller than those of any of the other fundamental fermions suggests radically new physics, perhaps originating at the GUT or Planck Scale, or perhaps the existence of new spatial dimensions. In some sense we know that the Standard Model is broken, but we don't know how it is broken. Whatever the origin of the observed neutrino masses and mixing, it is likely to require a profound extension to our picture of the physical world. The first steps in understanding this revolutionary new physics are to pin down the measurable parameters and to address the next round of basic questions: (1) Are there only three neutrino flavors, or do light, sterile neutrinos exist? (2) If there are only three generations, there is one angle ({theta}{sub 13}) in the mixing matrix that is unmeasured. How large is it? (3) Which of the two possible orderings of the neutrino mass eigenstates applies? (4) If {theta}{sub 13} is large enough one it may be possible to measure the quantum-mechanical phase {delta}. If {theta}{sub 13} and {delta} are non-zero there will be CP violation in the lepton sector. These questions can be addressed by accelerator based neutrino oscillation experiments. The answers will guide our understanding of what lies beyond the Standard Model, and whether the new physics provides an explanation for the baryon asymmetry of the Universe (via leptogenesis), or provides deep insight into the connection between quark and lepton properties (via Grand Unified Theories), or perhaps leads to an understanding of one of the most profound questions in physics: Why are there three generations of quarks and leptons? The answers may well further challenge our picture of the physical world, and will certainly have important implications for our understanding of cosmology and the evolution of the early Universe. The current Fermilab Program is an important part of the world-wide accelerator based effort to explore and understand the physics of neutrino oscillations. By early 2005, with both MINOS and MiniBooNE taking data, Fermilab will be able to answer some of the most pressing first-round questions raised by the discovery that neutrinos have mass. Fermilab's high-intensity neutrino beams are derived from 8- and 120-GeV proton beams. MiniBooNE is currently taking data using 8 GeV Protons from the Booster. The 120 GeV NuMI beam will start to operate in early 2005 using a 0.25 MW proton beam power from the Main Injector. Future neutrino programs will build on these existing facilities. New short and long baseline experiments have been proposed. There are proposals to increase the available number of protons at 8 and 120 GeV with the goal of addressing the full range of questions presented by neutrino oscillations. Key to that vision is a new intense proton source that usually is referred to as the Proton Driver.

  5. Neutron-Proton Radii in N \\approx Z Nuclei

    E-Print Network [OSTI]

    N. Auerbach

    2010-06-10T23:59:59.000Z

    A simple formula is derived that describes how the Coulomb interaction affects the proton radius in nuclei. It determines the difference between neutron and proton radii in nuclei with N approx Z. It also provides an estimate for the difference between the radii of the Z core neutrons and the protons in nuclei with a large neutron excess. The results obtained from the derived formula are compared with radii calculated in a Skyrme Hartree-Fock calculation.

  6. COMPACT ACCELERATOR CONCEPT FOR PROTON THERAPY

    SciTech Connect (OSTI)

    Caporaso, G; Sampayan, S; Chen, Y; Harris, J; Hawkins, S; Holmes, C; Krogh, M; Nelson, S; Nunnally, W; Paul, A; Poole, B; Rhodes, M; Sanders, D; Selenes, K; Sullivan, J; Wang, L; Watson, J

    2006-08-18T23:59:59.000Z

    A new type of compact induction accelerator is under development at the Lawrence Livermore National Laboratory that promises to increase the average accelerating gradient by at least an order of magnitude over that of existing induction machines. The machine is based on the use of high gradient vacuum insulators, advanced dielectric materials and switches and is being developed as a compact flash x-ray radiography source. Research describing an extreme variant of this technology aimed at proton therapy for cancer will be presented.

  7. Radiative proton capture on $^6$He

    E-Print Network [OSTI]

    E. Sauvan; F. M. Marqués; H. W. Wilschut; N. A. Orr

    2001-02-20T23:59:59.000Z

    Radiative capture of protons is investigated as a probe of clustering in nuclei far from stability. The first such measurement on a halo nucleus is reported here for the reaction $^6$He(p,$\\gamma$) at 40 MeV. Capture into $^7$Li is observed as the strongest channel. In addition, events have been recorded that may be described by quasi-free capture on a halo neutron, the $\\alpha$ core and $^5$He. The possibility of describing such events by capture into the continuum of $^7$Li is also discussed.

  8. Proton Energy Systems Inc | 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 onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere I GeothermalPotentialBiopowerSolidGenerationMethod Jump to:This propertyVolume JumpProtean PowerProton Energy

  9. Probing the Proton's Weak Side | Jefferson Lab

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible forPortsmouth/Paducah47,193.70 Hg Mercury 35 Br BromineProbing the Proton's Weak Side

  10. Protons Pair Up With Neutrons | Jefferson Lab

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible forPortsmouth/Paducah47,193.70 HgPromisingProtectingSciTechProtonEmbargoed: Not for

  11. Dynamical effects in proton breakup from exotic nuclei

    SciTech Connect (OSTI)

    Bonaccorso, Angela; Kumar, Ravinder [INFN, Sez. di Pisa, Largo B. Pontecorvo 3, 56127 Pisa (Italy); INFN, Sez. di Pisa, Largo B. Pontecorvo 3, 56127 Pisa and Department of Physics, Deenbandhu Chhoturam University of Science and Technology, Murthal, Sonepat, Haryana, 131039 (India)

    2012-10-20T23:59:59.000Z

    This contribution discusses dynamical effects in proton breakup from a weakly bound state in an exotic nucleus on a heavy target. The Coulomb interactions between the proton and the core and the proton and the target are treated to all orders, including also the full multipole expansion of the Coulomb potential. The dynamics of proton Coulomb breakup is compared to that of an equivalent neutron of larger binding energy in order to elucidate the differences with the well understood neutron breakup mechanism. A number of experimentally measurable observables such as parallel momentum distributions, proton angular distributions and total breakup cross sections can be calculated. With respect to nuclear breakup it is found that a proton behaves exactly as a neutron of larger binding energy. The extra 'effective energy' is due to the combined core-target Coulomb barrier. In Coulomb breakup we distinguish the effect of the core-target Coulomb potential (called recoil effect), with respect to which the proton behaves again as a more bound neutron, from the direct proton-target Coulomb potential. The latter gives cross sections about an order of magnitude larger than the recoil term. The two effects give rise to complicated interferences in the parallel momentum distributions. They are instead easily separable in the proton angular distributions which are therefore suggested as a very useful observable for future experimental studies.

  12. advanced protonic conductor: Topics by E-print Network

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

    FTIR and IINS of the protons and for the related vibrational modes. Inelastic incoherent neutron scattering (IINS) spectra Schuck, Gtz 3 Lead Nanopowder as Advanced...

  13. alamos proton storage: Topics by E-print Network

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

    Blalock 2012-06-07 2 PhysicsHighlight Proton radiography at Los Alamos National Laboratory Materials Science Websites Summary: ), where the extreme pressures have induced a...

  14. Comment on 'New Insights in the Electrocatalytic Proton Reduction...

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

    investigation of the mechanism of oxidation of H2 proton reduction using a model nickel complex for nickel-based electrocatalysts with cyclic phosphorous ligands...

  15. The contribution of strange quarks to the proton magnetic moment

    E-Print Network [OSTI]

    G. Dillon; G. Morpurgo

    2006-02-20T23:59:59.000Z

    This paper deals with how to extract the s-s(bar) contribution to the proton magnetic moment from the experiments

  16. The proton gyromagnetic g-factor: an electromagnetic model

    E-Print Network [OSTI]

    G. Sardin

    2009-12-25T23:59:59.000Z

    So far, the Standard Model of Elementary Particles has not succeeded getting a trustworthy account of the proton spin, which remains an enigma. This hindrance is known as the proton spin crisis, owing to the experimental evidence already from 1988 suggesting that little or none of the proton spin would come from the spin of the quarks. This prompted theorists to a flood of guessworks about the proton spin. Since it remains unsolved, in the framework of new physics an exploratory approach based on a novel paradigm is proposed, which brings a renewed access to this challenge, through its reciprocal relationship with the g-factor.

  17. Proton Channel Orientation in Block-Copolymer Electrolyte Membranes

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

    Proton Channel Orientation in Block-Copolymer Electrolyte Membranes Print Fuel cells have the potential to provide power for a wide variety of applications ranging from electronic...

  18. affecting proton exchange: Topics by E-print Network

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

    stress applied to the electrode area of a Proton Exchange Membrane (PEM) fuel cell is known to significantly affect power output. In practice, electrode stress arises...

  19. annealed proton exchanged: Topics by E-print Network

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

    characterized and integrated in Membrane-Electrodes Assembly to be tested in fuel cell operating conditions, mobile or stationary), Proton Exchange Membrane Fuel Cells...

  20. Physics Highlight Proton radiography at Los Alamos National Laboratory

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

    to enhance the signal from selected materials. Using the proton beam from a particle accelerator allows for multiple images taken at a wide range of intervals, capturing a...

  1. Proton Exchange Membrane Fuel Cells for Electrical Power Generation...

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

    SANDIA REPORT SAND2011-3119 Unlimited Release Printed May 2011 Proton Exchange Membrane Fuel Cells for Electrical Power Generation On-Board Commercial Airplanes Joseph W. Pratt,...

  2. Shuttle-mediated proton pumping across the inner mitochondrial membrane

    E-Print Network [OSTI]

    Anatoly Yu. Smirnov; Sergey E. Savel'ev; Franco Nori

    2008-06-19T23:59:59.000Z

    Shuttle-assisted charge transfer is pivotal for the efficient energy transduction from the food-stuff electrons to protons in the respiratory chain of animal cells and bacteria. The respiratory chain consists of four metalloprotein Complexes (I-IV) embedded in the inner membrane of a mitochondrion. Three of these complexes pump protons across the membrane, fuelled by the energy of food-stuff electrons. Despite extensive biochemical and biophysical studies, the physical mechanism of this proton pumping is still not well understood. Here we present a nanoelectromechanical model of the electron-driven proton pump related to the second loop of the respiratory chain, where a lipid-soluble ubiquinone molecule shuttles between the Complex I and Complex III, carrying two electrons and two protons. We show that the energy of electrons can be converted to the transmembrane proton potential gradient via the electrostatic interaction between electrons and protons on the shuttle. We find that the system can operate either as a proton pump, or, in the reverse regime, as an electron pump. For membranes with various viscosities, we demonstrate that the uphill proton current peaks near the body temperature $T \\approx 37 ^{\\circ}$C.

  3. Fast timing detectors for forward protons at the LHC

    SciTech Connect (OSTI)

    Albrow, Michael; /Fermilab

    2011-04-01T23:59:59.000Z

    The author discusses the development of high precision timing detectors for high momentum protons at the LHC, and their application in studying exclusive Higgs boson production.

  4. The shape of the proton at high energies

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

    Schlichting, Soren [Brookhaven National Lab. (BNL), Upton, NY (United States); Schenke, Bjorn [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2014-12-01T23:59:59.000Z

    We present first calculations of the fluctuating gluon distribution in a proton as a function of impact parameter and rapidity employing the functional Langevin form of the JIMWLK renormalization group equation. We demonstrate that when including effects of confinement by screening the long range Coulomb field of the color charges, the evolution is unitary. The large-x structure of the proton, characterized by the position of three valence quarks, retains an effect on the proton shape down to very small values of x. We determine the dipole scattering amplitude as a function of impact parameter and dipole size and extract the rapidity evolution of the saturation scale and the proton radius.

  5. BETA-DELAYED PROTON EMISSION IN NEUTRON-DEFICIENT LRNTHANIDE ISOTOPES

    E-Print Network [OSTI]

    Witmarth, P.A.

    2010-01-01T23:59:59.000Z

    and 6 first generated on a Vax™ mainframe, then capturedspectra were analyzed with a Vax version of SAMFO [Rou69], afloppies were sent to the Vax via the file transfer program

  6. Proton form factors and two-photon exchange contribution to elastic electron-proton scattering

    E-Print Network [OSTI]

    and unpolarized data! R. C. Walker, et al. PRD 49 (1994) 5671. I. A. Qattan, et al. PRL 94 (2005) 142301. M. K. Jones, et al. PRL 84 (2000) 1398. V. Punjabi, et al. PRC 71 (2005) 055202. O. Gayou, et al. PRL 88 (2002) 092301. A. J. R. Puckett, et al. PRL 104 (2010) 242301. Alexander Gramolin (Budker INP) Proton

  7. Gamma-Ray Emission From Crushed Clouds in Supernova Remnants

    SciTech Connect (OSTI)

    Uchiyama, Yasunobu; Blandford, Roger D.; Funk, Stefan; /SLAC; Tajima, Hiroyasu; /Nagoya U., Solar-Terrestrial Environ. Lab.; Tanaka, Takaaki; /KIPAC, Menlo Park; ,

    2010-10-27T23:59:59.000Z

    It is shown that the radio and gamma-ray emission observed from newly-found 'GeV-bright' supernova remnants (SNRs) can be explained by a model, in which a shocked cloud and shock-accelerated cosmic rays (CRs) frozen in it are simultaneously compressed by the supernova blastwave as a result of formation of a radiative cloud shock. Simple reacceleration of pre-existing CRs is generally sufficient to power the observed gamma-ray emission through the decays of {pi}{sup 0}-mesons produced in hadronic interactions between high-energy protons (nuclei) and gas in the compressed-cloud layer. This model provides a natural account of the observed synchrotron radiation in SNRs W51C, W44 and IC 443 with flat radio spectral index, which can be ascribed to a combination of secondary and reaccelerated electrons and positrons.

  8. Proton in the well and through the desolvation barrier Armen Y. Mulkidjanian

    E-Print Network [OSTI]

    Steinhoff, Heinz-Jürgen

    Review Proton in the well and through the desolvation barrier Armen Y. Mulkidjanian A.N. Belozersky proton well was suggested by Peter Mitchell to account for the energetic equivalence of the chemical (pH) and electrical () components of the proton-motive force. The proton well was defined as a proton

  9. Low Energy Barrier Proton Transfer in Protonated Benzene-Water Complex Eugene S. Kryachko and Minh Tho Nguyen*

    E-Print Network [OSTI]

    Nguyen, Minh Tho

    Low Energy Barrier Proton Transfer in Protonated Benzene-Water Complex Eugene S. Kryachko and Minh-bonded benzene-water complex is studied at the MP2/6-31+G(d,p) computational level. It is shown that, contrary to the fact that benzene is more basic than water by 13.5 kcal/mol, the excess proton favors to reside

  10. Neutron Stars Opacity and Proton Fraction

    E-Print Network [OSTI]

    P. N. Alcain; C. O. Dorso

    2015-02-03T23:59:59.000Z

    Background: In neutron stars the nucleons are submitted to extreme conditions. The study of this natural occurring objects can lead to further understanding of the behaviour of nuclear matter in highly asymmetric nuclei. Among the characteristics of neutron stars, its neutrino absorption - associated to structural inhomoegeneities - stands out as one of the possible magnitudes linked to an observable. Purpose: We have carried out a systematic study of this neutrino absorption for different thermodynamic conditions in order to assess the impact that the structure has on it. Method: We study the dynamics of nucleons in conditions according to the neutron star crust with a semiclassical molecular dynamics model, for different densities, proton fractions and temperature, we calculate the long range opacity and the cluster distribution. Results: The neutrino absorption, the main mechanism for neutron stars cooldown, takes its highest value for temperatures and densities low compared with the inner crust, and a proton fraction is close to the symmetric case $x=0.5$. Conclusions: Within the used model the neutrinos are absorbed mostly close to the surface of the neutron star. Also, for high temperatures, a large cluster still exists, but the appearance of several small-sized clusters smears out the very long range order needed for neutrino absorption.

  11. Ion/proton-conducting apparatus and method

    DOE Patents [OSTI]

    Yates, Matthew; Xue, Wei

    2014-12-23T23:59:59.000Z

    A c-axis-oriented HAP thin film synthesized by seeded growth on a palladium hydrogen membrane substrate. An exemplary synthetic process includes electrochemical seeding on the substrate, and secondary and tertiary hydrothermal treatments under conditions that favor growth along c-axes and a-axes in sequence. By adjusting corresponding synthetic conditions, an HAP this film can be grown to a controllable thickness with a dense coverage on the underlying substrate. The thin films have relatively high proton conductivity under hydrogen atmosphere and high temperature conditions. The c-axis oriented films may be integrated into fuel cells for application in the intermediate temperature range of 200-600.degree. C. The electrochemical-hydrothermal deposition technique may be applied to create other oriented crystal materials having optimized properties, useful for separations and catalysis as well as electronic and electrochemical applications, electrochemical membrane reactors, and in chemical sensors. Additional high-density and gas-tight HAP film compositions may be deposited using a two-step deposition method that includes an electrochemical deposition method followed by a hydrothermal deposition method. The two-step method uses a single hydrothermal deposition solution composition. The method may be used to deposit HAP films including but not limited to at least doped HAP films, and more particularly including carbonated HAP films. In addition, the high-density and gas-tight HAP films may be used in proton exchange membrane fuel cells.

  12. Controlled spontaneous emission

    E-Print Network [OSTI]

    Jae-Seung Lee; Mary A. Rohrdanz; A. K. Khitrin

    2007-07-03T23:59:59.000Z

    The problem of spontaneous emission is studied by a direct computer simulation of the dynamics of a combined system: atom + radiation field. The parameters of the discrete finite model, including up to 20k field oscillators, have been optimized by a comparison with the exact solution for the case when the oscillators have equidistant frequencies and equal coupling constants. Simulation of the effect of multi-pulse sequence of phase kicks and emission by a pair of atoms shows that both the frequency and the linewidth of the emitted spectrum could be controlled.

  13. Optimal irreversible stimulated emission

    E-Print Network [OSTI]

    D Valente; Y Li; J P Poizat; J M Gerard; L C Kwek; M F Santos; A Auffeves

    2012-08-28T23:59:59.000Z

    We studied the dynamics of an initially inverted atom in a semi-infinite waveguide, in the presence of a single propagating photon. We show that atomic relaxation is enhanced by a factor of 2, leading to maximal bunching in the output field. This optimal irreversible stimulated emission is a novel phenomenon that can be observed with state-of-the-art solid-state atoms and waveguides. When the atom interacts with two one-dimensional electromagnetic environments, the preferential emission in the stimulated field can be exploited to efficiently amplify a classical or a quantum state.

  14. Systematic trends in beta-delayed particle emitting nuclei: The case of beta-p-alpha emission from 21Mg

    E-Print Network [OSTI]

    M. V. Lund; M. J. G. Borge; J. A. Briz; J. Cederkäll; H. O. U. Fynbo; J. H. Jensen; B. Jonson; K. L. Laursen; T. Nilsson; A. Perea; V. Pesudo; K. Riisager; O. Tengblad

    2015-06-12T23:59:59.000Z

    We have observed beta+-delayed alpha and p-alpha emission from the proton-rich nucleus 21Mg produced at the ISOLDE facility at CERN. The assignments were cross-checked with a time distribution analysis. This is the third identified case of beta-p-alpha emission. We discuss the systematic of beta-delayed particle emission decays, show that our observed decays fit naturally into the existing pattern, and argue that the patterns are to a large extent caused by odd-even effects.

  15. Emissions Trading and Air Toxics Emissions: RECLAIM and Toxics Regulation in the South Coast Air Basin

    E-Print Network [OSTI]

    Cohen, Nancy J.

    1993-01-01T23:59:59.000Z

    Emissions Trading and Air Toxics Emissions: RECLAIM anda mar- ket-based emissions trading program called theimpacts cre- ated by emissions trading programs that affect

  16. Proton Radiography Studies for Proton CT M. Petterson, N. Blumenkrantz, J. Feldt, J. Heimann, D. Lucia, A. Seiden, D. C. Williams, H. F.-W. Sadrozinski,

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    Proton Radiography Studies for Proton CT M. Petterson, N. Blumenkrantz, J. Feldt, J. Heimann, D. Randazzo, V. Sipala Abstract­We report the results of a beam experiment to develop proton Computed of a phantom to predict the path of the proton within the phantom and of a crystal calorimeter to measure

  17. A CR-hydro-NEI Model of the Structure and Broadband Emission from Tycho's SNR

    E-Print Network [OSTI]

    Slane, P; Ellison, D C; Patnaude, D J; Hughes, J P; Eriksen, K A; Castro, D; Nagataki, S

    2014-01-01T23:59:59.000Z

    Tycho's supernova remnant (SNR) is well-established as a source of particle acceleration to very high energies. Constraints from numerous studies indicate that the observed gamma-ray emission results primarily from hadronic processes, providing direct evidence of highly relativistic ions that have been accelerated by the SNR. Here we present an investigation of the dynamical and spectral evolution of Tycho's SNR by carrying out hydrodynamical simulations that include diffusive shock acceleration of particles in the amplified magnetic field at the forward shock of the SNR. Our simulations provide a consistent view of the shock positions, the nonthermal emission, the thermal X-ray emission from the forward shock, and the brightness profiles of the radio and X-ray emission. We compare these with the observed properties of Tycho to determine the density of the ambient material, the particle acceleration efficiency and maximum energy, the accelerated electron to-proton ratio, and the properties of the shocked gas ...

  18. Graphene Coating Coupled Emission

    E-Print Network [OSTI]

    Shyamasundar, R.K.

    Graphene Coating Coupled Emission A COMSET, A single sheet of sp2-hybridized carbon atoms, called of graphene and its unique properties, I will present amplification of surface graphene-Ag hybrid films which when graphene is used as the spacer layer in a conventional Ag- harnessed the nonlinear properties

  19. Secondary emission gas chamber

    E-Print Network [OSTI]

    V. In'shakov; V. Kryshkin; V. Skvortsov

    2014-12-10T23:59:59.000Z

    For a hadron calorimeter active element there is considered a gaseous secondary emis-sion detector (150 micron gap, 50 kV/cm). Such one-stage parallel plate chamber must be a radiation hard, fast and simple. A model of such detector has been produced, tested and some characteristics are presented.

  20. Low energy proton storage ring with longitudinal magnetic

    E-Print Network [OSTI]

    Low energy proton storage ring with longitudinal magnetic field and electron cooling M.I. Bryzgunov energy protons. In this particular case it is reaction for production of resonant gamma-quant (9.17 Me Electron cooling: compensates heating effects on internal target compensates energy losses on target

  1. Secondary neutrons in clinical proton radiotherapy: A charged issue

    E-Print Network [OSTI]

    Brenner, David Jonathan

    -body neutron dose, due to interactions of the protons with the scattering and collimating beam elements radiotherapy; Secondary neutrons; Second cancers; Passive scattering The development of hospital-based proton on establishing the neutron doses involved [7­20], there is still no agree- ment about whether these scattered

  2. Proton dripline in a new formula for nuclear binding energy

    E-Print Network [OSTI]

    Chirashree Lahiri; G. Gangopadhyay

    2011-10-27T23:59:59.000Z

    The location of the proton dripline in a new phenomenological mass formula is calculated. Predictions of different mass formulas for the dripline are compared. The implications of the new mass formula for rapid proton nucleosynthesis beyond $^{56}$Ni are discussed. It is seen that the new formula indicates that masses up to A=80 are easily synthesized in a typical X-ray burst.

  3. Storage Ring Proton EDM Yannis K. Semertzidis, BNL, August 2012

    E-Print Network [OSTI]

    Storage Ring Proton EDM Yannis K. Semertzidis, BNL, August 2012 for the Storage Ring EDM also help to shed light on the strong CP-problem, completing the standard model (SM). Storage ring EDM of highly polarized proton and deuteron beams are readily available. The storage time is entirely defined

  4. STOCHASTIC COOLING OF 200 MeV PROTONS

    E-Print Network [OSTI]

    Lambertson, G.

    2010-01-01T23:59:59.000Z

    7 - 1 1 , 1980 STOCHASTIC COOLING OF 200 MeV PROTONS Glen LT t l L8L 10757 STOCHASTIC COOLING OF ZOO HeV PROTONS* Glent i c a l and longitudinal cooling has been achieved a t the

  5. Proton root-mean-square radii and electron scattering

    E-Print Network [OSTI]

    Ingo Sick; Dirk Trautmann

    2014-07-07T23:59:59.000Z

    The standard procedure of extracting the proton root-mean-square radii from models for the Sachs form factors $G_e (q)$ and $G_m (q)$ fitted to elastic electron-proton scattering data %has a serious flaw. is more uncertain than traditionally assumed. The extrapolation of $G(q)$, from the region $q_{min} reliable $rms$-radii be determined.

  6. Epoxy-crosslinked sulfonated poly (phenylene) copolymer proton exchange membranes

    DOE Patents [OSTI]

    Hibbs, Michael (Albuquerque, NM); Fujimoto, Cy H. (Albuquerque, NM); Norman, Kirsten (Albuquerque, NM); Hickner, Michael A. (State College, PA)

    2010-10-19T23:59:59.000Z

    An epoxy-crosslinked sulfonated poly(phenylene) copolymer composition used as proton exchange membranes, methods of making the same, and their use as proton exchange membranes (PEM) in hydrogen fuel cells, direct methanol fuel cell, in electrode casting solutions and electrodes, and in sulfur dioxide electrolyzers. These improved membranes are tougher, have higher temperature capability, and lower SO.sub.2 crossover rates.

  7. Method and apparatus for laser-controlled proton beam radiology

    DOE Patents [OSTI]

    Johnstone, Carol J. (Warrenville, IL)

    1998-01-01T23:59:59.000Z

    A proton beam radiology system provides cancer treatment and proton radiography. The system includes an accelerator for producing an H.sup.- beam and a laser source for generating a laser beam. A photodetachment module is located proximate the periphery of the accelerator. The photodetachment module combines the H.sup.- beam and laser beam to produce a neutral beam therefrom within a subsection of the H.sup.- beam. The photodetachment module emits the neutral beam along a trajectory defined by the laser beam. The photodetachment module includes a stripping foil which forms a proton beam from the neutral beam. The proton beam is delivered to a conveyance segment which transports the proton beam to a patient treatment station. The photodetachment module further includes a laser scanner which moves the laser beam along a path transverse to the cross-section of the H.sup.- beam in order to form the neutral beam in subsections of the H.sup.- beam. As the scanning laser moves across the H.sup.- beam, it similarly varies the trajectory of the proton beam emitted from the photodetachment module and in turn varies the target location of the proton beam upon the patient. Intensity modulation of the proton beam can also be achieved by controlling the output of the laser.

  8. Method and apparatus for laser-controlled proton beam radiology

    DOE Patents [OSTI]

    Johnstone, C.J.

    1998-06-02T23:59:59.000Z

    A proton beam radiology system provides cancer treatment and proton radiography. The system includes an accelerator for producing an H{sup {minus}} beam and a laser source for generating a laser beam. A photodetachment module is located proximate the periphery of the accelerator. The photodetachment module combines the H{sup {minus}} beam and laser beam to produce a neutral beam therefrom within a subsection of the H{sup {minus}} beam. The photodetachment module emits the neutral beam along a trajectory defined by the laser beam. The photodetachment module includes a stripping foil which forms a proton beam from the neutral beam. The proton beam is delivered to a conveyance segment which transports the proton beam to a patient treatment station. The photodetachment module further includes a laser scanner which moves the laser beam along a path transverse to the cross-section of the H{sup {minus}} beam in order to form the neutral beam in subsections of the H{sup {minus}} beam. As the scanning laser moves across the H{sup {minus}} beam, it similarly varies the trajectory of the proton beam emitted from the photodetachment module and in turn varies the target location of the proton beam upon the patient. Intensity modulation of the proton beam can also be achieved by controlling the output of the laser. 9 figs.

  9. Computational Modeling and Optimization of Proton Exchange Membrane Fuel Cells

    E-Print Network [OSTI]

    Victoria, University of

    Computational Modeling and Optimization of Proton Exchange Membrane Fuel Cells by Marc Secanell and Optimization of Proton Exchange Membrane Fuel Cells by Marc Secanell Gallart Bachelor in Engineering cells. In this thesis, a computational framework for fuel cell analysis and optimization is presented

  10. DPA and Gas Production from Protons on W and Be

    E-Print Network [OSTI]

    McDonald, Kirk

    Production in Tungsten · Ran the Mu2e target in MARS15 using the following parameters: ­ 8 GeV protonsDPA and Gas Production from Protons on W and Be Brian Hartsell FNAL March 20, 2013 #12;DPA and Gas on Tungsten target ­ Gaussian distribution with 1mm X and Y sigma ­ 6mm diameter, 160mm length target ­ 3 bins

  11. Measurements of neutron dose equivalent for a proton therapy center using uniform scanning proton beams

    SciTech Connect (OSTI)

    Zheng Yuanshui; Liu Yaxi; Zeidan, Omar; Schreuder, Andries Niek; Keole, Sameer [ProCure Proton Therapy Center, 5901 West Memorial Road, Oklahoma City, Oklahoma 73142 (United States); INTEGRIS Cancer Insititute, 5911 West Memorial Road, Oklahoma City, Oklahoma 73142 (United States); ProCure Proton Therapy Center, 5901 West Memorial Road, Oklahoma City, Oklahoma 73142 (United States); ProCure Treatment Centers, 420 North Walnut Street, Bloomington, Indiana 47404 (United States); ProCure Proton Therapy Center, 5901 West Memorial Road, Oklahoma City, Oklahoma 73142 (United States)

    2012-06-15T23:59:59.000Z

    Purpose: Neutron exposure is of concern in proton therapy, and varies with beam delivery technique, nozzle design, and treatment conditions. Uniform scanning is an emerging treatment technique in proton therapy, but neutron exposure for this technique has not been fully studied. The purpose of this study is to investigate the neutron dose equivalent per therapeutic dose, H/D, under various treatment conditions for uniform scanning beams employed at our proton therapy center. Methods: Using a wide energy neutron dose equivalent detector (SWENDI-II, ThermoScientific, MA), the authors measured H/D at 50 cm lateral to the isocenter as a function of proton range, modulation width, beam scanning area, collimated field size, and snout position. They also studied the influence of other factors on neutron dose equivalent, such as aperture material, the presence of a compensator, and measurement locations. They measured H/D for various treatment sites using patient-specific treatment parameters. Finally, they compared H/D values for various beam delivery techniques at various facilities under similar conditions. Results: H/D increased rapidly with proton range and modulation width, varying from about 0.2 mSv/Gy for a 5 cm range and 2 cm modulation width beam to 2.7 mSv/Gy for a 30 cm range and 30 cm modulation width beam when 18 Multiplication-Sign 18 cm{sup 2} uniform scanning beams were used. H/D increased linearly with the beam scanning area, and decreased slowly with aperture size and snout retraction. The presence of a compensator reduced the H/D slightly compared with that without a compensator present. Aperture material and compensator material also have an influence on neutron dose equivalent, but the influence is relatively small. H/D varied from about 0.5 mSv/Gy for a brain tumor treatment to about 3.5 mSv/Gy for a pelvic case. Conclusions: This study presents H/D as a function of various treatment parameters for uniform scanning proton beams. For similar treatment conditions, the H/D value per uncollimated beam size for uniform scanning beams was slightly lower than that from a passive scattering beam and higher than that from a pencil beam scanning beam, within a factor of 2. Minimizing beam scanning area could effectively reduce neutron dose equivalent for uniform scanning beams, down to the level close to pencil beam scanning.

  12. Proton Therapy Coverage for Prostate Cancer Treatment

    SciTech Connect (OSTI)

    Vargas, Carlos [University of Florida Proton Therapy Institute, Jacksonville, FL (United States); Department of Radiation Oncology, University of Florida College of Medicine, Gainesville, FL (United States)], E-mail: c2002@ufl.edu; Wagner, Marcus; Mahajan, Chaitali [University of Florida Proton Therapy Institute, Jacksonville, FL (United States); Indelicato, Daniel [Department of Radiation Oncology, University of Florida College of Medicine, Gainesville, FL (United States); Fryer, Amber; Falchook, Aaron; Horne, David C.; Chellini, Angela; McKenzie, Craig C.; Lawlor, Paula C.; Li Zuofeng; Lin Liyong; Keole, Sameer [University of Florida Proton Therapy Institute, Jacksonville, FL (United States)

    2008-04-01T23:59:59.000Z

    Purpose: To determine the impact of prostate motion on dose coverage in proton therapy. Methods and Materials: A total of 120 prostate positions were analyzed on 10 treatment plans for 10 prostate patients treated using our low-risk proton therapy prostate protocol (University of Florida Proton Therapy Institute 001). Computed tomography and magnetic resonance imaging T{sub 2}-weighted turbo spin-echo scans were registered for all cases. The planning target volume included the prostate with a 5-mm axial and 8-mm superoinferior expansion. The prostate was repositioned using 5- and 10-mm one-dimensional vectors and 10-mm multidimensional vectors (Points A-D). The beam was realigned for the 5- and 10-mm displacements. The prescription dose was 78 Gy equivalent (GE). Results: The mean percentage of rectum receiving 70 Gy (V{sub 70}) was 7.9%, the bladder V{sub 70} was 14.0%, and the femoral head/neck V{sub 50} was 0.1%, and the mean pelvic dose was 4.6 GE. The percentage of prostate receiving 78 Gy (V{sub 78}) with the 5-mm movements changed by -0.2% (range, 0.006-0.5%, p > 0.7). However, the prostate V{sub 78} after a 10-mm displacement changed significantly (p < 0.003) with different movements: 3.4% (superior), -5.6% (inferior), and -10.2% (posterior). The corresponding minimal doses were also reduced: 4.5 GE, -4.7 GE, and -11.7 GE (p {<=} 0.003). For displacement points A-D, the clinical target volume V{sub 78} coverage had a large and significant reduction of 17.4% (range, 13.5-17.4%, p < 0.001) in V{sub 78} coverage of the clinical target volume. The minimal prostate dose was reduced 33% (25.8 GE), on average, for Points A-D. The prostate minimal dose improved from 69.3 GE to 78.2 GE (p < 0.001) with realignment for 10-mm movements. Conclusion: The good dose coverage and low normal doses achieved for the initial plan was maintained with movements of {<=}5 mm. Beam realignment improved coverage for 10-mm displacements.

  13. Polarization diagnostics of proton beams in solar flares

    E-Print Network [OSTI]

    Jiri Stepan

    2007-02-02T23:59:59.000Z

    We review the problem of proton beam bombardment of solar chromosphere considering the self-consistent NLTE polarized radiation transfer in hydrogen lines. Several observations indicate a linear polarization of the H-alpha line of the order of 5% or higher and preferentially in radial direction. This polarization is often explained as anisotropic collisional excitation of the n=3 level by vertical proton beams. Our calculations indicate that deceleration of the proton beam with initial power-law energy distribution together with increased electron and proton densities in the H-alpha forming layers lead to a negligible line polarization. Thus the proton beams seem not to be a good candidate for explanation of the observed polarization degree. On the other hand, the effect of electric return currents could perhaps provide a better explanation of the observed linear polarization. We report the new calculations of this effect.

  14. Designer proton-channel transgenic algae for photobiological hydrogen production

    DOE Patents [OSTI]

    Lee, James Weifu (Knoxville, TN)

    2011-04-26T23:59:59.000Z

    A designer proton-channel transgenic alga for photobiological hydrogen production that is specifically designed for production of molecular hydrogen (H.sub.2) through photosynthetic water splitting. The designer transgenic alga includes proton-conductive channels that are expressed to produce such uncoupler proteins in an amount sufficient to increase the algal H.sub.2 productivity. In one embodiment the designer proton-channel transgene is a nucleic acid construct (300) including a PCR forward primer (302), an externally inducible promoter (304), a transit targeting sequence (306), a designer proton-channel encoding sequence (308), a transcription and translation terminator (310), and a PCR reverse primer (312). In various embodiments, the designer proton-channel transgenic algae are used with a gas-separation system (500) and a gas-products-separation and utilization system (600) for photobiological H.sub.2 production.

  15. Allocation of emission rights Economic incentives for emission

    E-Print Network [OSTI]

    for all countries High cost effectiviness:High cost effectiviness: International Emission trading Fairness NAM Department of Physical Resource Theory #12;Financial flows from emissions trading 450 ppmGDP SAS CPA WEU NAM Department of Physical Resource Theory #12;Financial flows from emissions trading 450

  16. Nonadiabatic dynamics for processes involving multiple avoided curve crossings: Double proton transfer and proton-coupled electron transfer

    E-Print Network [OSTI]

    Hammes-Schiffer, Sharon

    Nonadiabatic dynamics for processes involving multiple avoided curve crossings: Double proton transfer and proton-coupled electron transfer reactions Jian-Yun Fang and Sharon Hammes June 1997; accepted 26 August 1997 The extension of the surface hopping method ``molecular dynamics

  17. Ion-/proton-conducting apparatus and method

    DOE Patents [OSTI]

    Yates, Matthew (Penfield, NY); Liu, Dongxia (Rochester, NY)

    2011-05-17T23:59:59.000Z

    A c-axis-oriented HAP thin film synthesized by seeded growth on a palladium hydrogen membrane substrate. An exemplary synthetic process includes electrochemical seeding on the substrate, and secondary and tertiary hydrothermal treatments under conditions that favor growth along c-axes and a-axes in sequence. By adjusting corresponding synthetic conditions, an HAP this film can be grown to a controllable thickness with a dense coverage on the underlying substrate. The thin films have relatively high proton conductivity under hydrogen atmosphere and high temperature conditions. The c-axis oriented films may be integrated into fuel cells for application in the intermediate temperature range of 200-600.degree. C. The electrochemical-hydrothermal deposition technique may be applied to create other oriented crystal materials having optimized properties, useful for separations and catalysis as well as electronic and electrochemical applications, electrochemical membrane reactors, and in chemical sensors.

  18. Strange Electric Form Factor of the Proton

    E-Print Network [OSTI]

    D. B. Leinweber; S. Boinepalli; A. W. Thomas; P. Wang; A. G. Williams; R. D. Young; J. M. Zanotti; J. B. Zhang

    2006-07-18T23:59:59.000Z

    By combining the constraints of charge symmetry with new chiral extrapolation techniques and recent low-mass quenched lattice QCD simulations of the individual quark contributions to the electric charge radii of the baryon octet, we obtain an accurate determination of the strange electric charge radius of the proton. While this analysis provides a value for G_E^s(Q^2=0.1 GeV^2) in agreement with the best current data, the theoretical error is comparable with that expected from future HAPPEx results from JLab. Together with the earlier determination of G_M^s, this result considerably constrains the role of hidden flavor in the structure of the nucleon.

  19. Causality bounds for neutron-proton scattering

    E-Print Network [OSTI]

    Serdar Elhatisari; Dean Lee

    2012-07-25T23:59:59.000Z

    We consider the constraints of causality and unitarity for the low-energy interactions of protons and neutrons. We derive a general theorem that non-vanishing partial-wave mixing cannot be reproduced with zero-range interactions without violating causality or unitarity. We define and calculate interaction length scales which we call the causal range and the Cauchy-Schwarz range for all spin channels up to J = 3. For some channels we find that these length scales are as large as 5 fm. We investigate the origin of these large lengths and discuss their significance for the choice of momentum cutoff scales in effective field theory and universality in many-body Fermi systems.

  20. Nanostructured polymer membranes for proton conduction

    DOE Patents [OSTI]

    Balsara, Nitash Pervez; Park, Moon Jeong

    2013-06-18T23:59:59.000Z

    Polymers having an improved ability to entrain water are characterized, in some embodiments, by unusual humidity-induced phase transitions. The described polymers (e.g., hydrophilically functionalized block copolymers) have a disordered state and one or more ordered states (e.g., a lamellar state, a gyroid state, etc.). In one aspect, the polymers are capable of undergoing a disorder-to-order transition while the polymer is exposed to an increasing temperature at a constant relative humidity. In some aspects the polymer includes a plurality of portions, wherein a first portion forms proton-conductive channels within the membrane and wherein the channels have a width of less than about 6 nm. The described polymers are capable of entraining and preserving water at high temperature and low humidity. Surprisingly, in some embodiments, the polymers are capable of entraining greater amounts of water with the increase of temperature. The polymers can be used in Polymer Electrolyte Membranes in fuel cells.

  1. TWO-PROTON CORRELATION MEASUREMENTS IN 800- AND 400- MeV/NUCLEON HEAVY-ION REACTIONS

    E-Print Network [OSTI]

    Tanihata, I.

    2013-01-01T23:59:59.000Z

    of California. Two-Proton Correlation Measurements in 800-angular correlations of two protons in collisions of C +c. Cc.m. indicates the free proton-proton elastic scattering

  2. Energy spectrum control for modulated proton beams

    SciTech Connect (OSTI)

    Hsi, Wen C.; Moyers, Michael F.; Nichiporov, Dmitri; Anferov, Vladimir; Wolanski, Mark; Allgower, Chris E.; Farr, Jonathan B.; Mascia, Anthony E.; Schreuder, Andries N. [Midwest Proton Radiotherapy Institute, Bloomington, Indiana 47408 and University Florida Proton Therapy Institute, Jacksonville, Florida 32206 (United States); Proton Therapy, Inc., Colton, California 92324 (United States); Indiana University Cyclotron Facility, Bloomington, Indiana 47408 (United States); Midwest Proton Radiotherapy Institute, Bloomington, Indiana 47408 and University Florida Proton Therapy Institute, Jacksonville, Florida 32206 (United States); Midwest Proton Radiotherapy Institute, Bloomington, Indiana 47408 (United States); University Florida Proton Therapy Institute, Jacksonville, Florida 32206 (United States) and Westdeutsches Protonentherapiezentrum, Universitaetsklinikum, Hufelandstrasse 55, 45147 Essen (Germany); Midwest Proton Radiotherapy Institute, Bloomington, Indiana 47408 (United States); University Florida Proton Therapy Institute, Jacksonville, Florida 32206 (United States) and ProCure Treatment Centers, Inc., Bloomington, Indiana 47404 (United States)

    2009-06-15T23:59:59.000Z

    In proton therapy delivered with range modulated beams, the energy spectrum of protons entering the delivery nozzle can affect the dose uniformity within the target region and the dose gradient around its periphery. For a cyclotron with a fixed extraction energy, a rangeshifter is used to change the energy but this produces increasing energy spreads for decreasing energies. This study investigated the magnitude of the effects of different energy spreads on dose uniformity and distal edge dose gradient and determined the limits for controlling the incident spectrum. A multilayer Faraday cup (MLFC) was calibrated against depth dose curves measured in water for nonmodulated beams with various incident spectra. Depth dose curves were measured in a water phantom and in a multilayer ionization chamber detector for modulated beams using different incident energy spreads. Some nozzle entrance energy spectra can produce unacceptable dose nonuniformities of up to {+-}21% over the modulated region. For modulated beams and small beam ranges, the width of the distal penumbra can vary by a factor of 2.5. When the energy spread was controlled within the defined limits, the dose nonuniformity was less than {+-}3%. To facilitate understanding of the results, the data were compared to the measured and Monte Carlo calculated data from a variable extraction energy synchrotron which has a narrow spectrum for all energies. Dose uniformity is only maintained within prescription limits when the energy spread is controlled. At low energies, a large spread can be beneficial for extending the energy range at which a single range modulator device can be used. An MLFC can be used as part of a feedback to provide specified energy spreads for different energies.

  3. Proton-proton correlation function for the pp -> pp + eta and pp -> pp + pions reactions

    E-Print Network [OSTI]

    P. Klaja; P. Moskal

    2010-08-30T23:59:59.000Z

    For the very first time, the correlation femtoscopy method is applied to a kinematically complete measurement of meson production in the collisions of hadrons. The shape of the two-proton correlation function derived for the pp -> ppeta reaction differs from that for the pp -> pp(pions) and both do not show a peak structure opposite to results determined for inclusive measurements of heavy ion collisions.

  4. Field emission from organic materials

    E-Print Network [OSTI]

    Kymissis, Ioannis, 1977-

    2003-01-01T23:59:59.000Z

    Field emission displays (FEDs) show great promise as high performance flat panel displays. The light emission process is efficient, long lifetimes are possible with high brightness, and bright passive matrix displays can ...

  5. Pion production in proton-proton collisions in a covariant one boson exchange model

    E-Print Network [OSTI]

    A. Engel; A. K. Dutt-Mazumder; R. Shyam; U. Mosel

    1996-01-18T23:59:59.000Z

    Motivated by the renewed interest in studying the pion production on nuclei with protons at few GeV incident energies, we investigate the pion production in proton-proton collisions over an energy range of 300 $MeV$ to 2 $GeV$. Starting from a realistic one-boson exchange model with parameters fitted to the amplitudes of the elastic nucleon-nucleon scattering, we perform fully covariant calculations for the total, double and triple differential cross-sections of the $p(p,n\\pi^+)p$ and $p(p,p\\pi^0)p$ reactions. The calculations incorporate the exchange of $\\pi, \\rho,\\omega$ and $\\sigma$ mesons and treat nucleon and delta isobar as intermediate states. We obtain a reasonably good agreement with the experimental data in the entire range of beam energies. The form of the covariant delta propagator, the cut-off parameter for the $\\pi NN$ and $\\pi N\\Delta$ vertex form factors and the energy dependence of the delta isobar decay width is investigated.

  6. Generalized z-scaling in proton-proton collisions at high energies

    E-Print Network [OSTI]

    Zborovský, I

    2006-01-01T23:59:59.000Z

    New generalization of z-scaling in inclusive particle production is proposed. The scaling variable z is fractal measure which depends on kinematical characteristics of the underlying sub-process expressed in terms of the momentum fractions x1 and x2 of the incoming protons. In the generalized approach, the x1 and x2 are functions of the momentum fractions ya and yb of the scattered and recoil constituents carried out by the inclusive particle and recoil object, respectively. The scaling function psi(z) for charged and identified hadrons produced in proton-proton collisions is constructed. The fractal dimensions and heat capacity of the produced medium entering definition of the z are established to obtain energy, angular and multiplicity independence of the psi(z). The scheme allows unique description of data on inclusive cross sections of charged particles, pions, kaons, antiprotons and lambdas at high energies. The obtained results are of interest to use z-scaling as a tool for searching for new physics phe...

  7. Fuels, Engines & Emissions | Clean Energy | ORNL

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

    Fuels, Engines, Emissions SHARE Fuels, Engines and Emissions Research Fuels, Engines, and Emissions research at Oak Ridge National Laboratory is helping identify ways to increase...

  8. Greenhouse gas emissions in biogas production systems

    E-Print Network [OSTI]

    Dittert, Klaus; Senbayram, Mehmet; Wienforth, Babette; Kage, Henning; Muehling, Karl H

    2009-01-01T23:59:59.000Z

    Cameron KC. Nitrous oxide emissions from two dairy pastureand land use on N 2 O emissions from an imperfectly drainedoptions for N 2 O emissions from differently managed

  9. 6, 57735796, 2006 Vehicular emissions

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    be partly responsible for lower CO2 and higher CO and NO emission factors. Also, a fast reduction the emission (in g/km) of key and non-regulated pollutants, such as CO2, CO, NO, SO2, NH3, HCHO, NMHC, dur-10 of pollutants, even from a super ultra-low emission vehicle (SULEV). The emissions of HC's, NOx, CO20 and CO2

  10. Low-Energy Nuclear Reactions of Protons in Host Metals at Picometre Distance

    SciTech Connect (OSTI)

    Heinrich Hora; George H. Miley; Jak C. Kelly

    2000-11-12T23:59:59.000Z

    A review is given for the explanation of the measurements of Miley et al. of a fully reproducible generation of nuclei of the whole periodic table by protons in host metals during a several-weeks reaction. Similar low-energy nuclear reactions (LENR) were observed by other groups. The fact that the heavy nuclides are not due to pollution can be seen from the fact that such very rare elements as thulium and terbium were detected by unique K-shell X-ray spectra. The nuclear reaction energy goes into the heavy nuclei as measured from much bigger traces in CR39 than from alphas. The fact that any reaction of the protons results in stable daughter nuclei is confirmed by the fact that the highest energy gain is resulting with stable reaction products. This has been explained in Ref. 2, and the energy gain for the heavy element generation by a compound reaction was discussed. The explanation is based on the model of the authors from 1989 to assume free motion of the protons contrary to localized crystalline states. A relation of the reaction time U on distance d of the reacting nuclei by a power law with an exponent 34.8 was derived. Based on few reproducible D-D reactions, a reaction time near the range of megaseconds and a reaction distance of nanometers was concluded. A splendid confirmation of the picometre-megasecond reactions was achieved by Li et al. from his direct quantum mechanical calculations of the hot fusion D-T reactions based on a one-step selective resonance tunneling model. Li et al. were able for the first time to derive the cross sections of the hot fusion. Li's application to picometre distance showed megasecond reaction times with no neutron or gamma emission. Because of the imaginary part in the Schroedinger potential, the problem of the level width is reduced by damping.

  11. 4, 507532, 2004 Emission uncertainty

    E-Print Network [OSTI]

    Boyer, Edmond

    and Physics Discussions Impact of different emission inventories on simulated tropospheric ozone over China The importance of emission inventory uncertainty on the simulation of summertime tro- pospheric Ozone over China has been analyzed using a regional chemical transport model. Three independent emissions inventories

  12. Low emissions diesel fuel

    DOE Patents [OSTI]

    Compere, A.L.; Griffith, W.L.; Dorsey, G.F.; West, B.H.

    1998-05-05T23:59:59.000Z

    A method and matter of composition for controlling NO{sub x} emissions from existing diesel engines. The method is achieved by adding a small amount of material to the diesel fuel to decrease the amount of NO{sub x} produced during combustion. Specifically, small amounts, less than about 1%, of urea or a triazine compound (methylol melamines) are added to diesel fuel. Because urea and triazine compounds are generally insoluble in diesel fuel, microemulsion technology is used to suspend or dissolve the urea or triazine compound in the diesel fuel. A typical fuel formulation includes 5% t-butyl alcohol, 4.5% water, 0.5% urea or triazine compound, 9% oleic acid, and 1% ethanolamine. The subject invention provides improved emissions in heavy diesel engines without the need for major modifications.

  13. Low emissions diesel fuel

    DOE Patents [OSTI]

    Compere, Alicia L. (Knoxville, TN); Griffith, William L. (Oak Ridge, TN); Dorsey, George F. (Farragut, TN); West, Brian H. (Kingston, TN)

    1998-01-01T23:59:59.000Z

    A method and matter of composition for controlling NO.sub.x emissions from existing diesel engines. The method is achieved by adding a small amount of material to the diesel fuel to decrease the amount of NO.sub.x produced during combustion. Specifically, small amounts, less than about 1%, of urea or a triazine compound (methylol melamines) are added to diesel fuel. Because urea and triazine compounds are generally insoluble in diesel fuel, microemulsion technology is used to suspend or dissolve the urea or triazine compound in the diesel fuel. A typical fuel formulation includes 5% t-butyl alcohol, 4.5% water, 0.5% urea or triazine compound, 9% oleic acid, and 1% ethanolamine. The subject invention provides improved emissions in heavy diesel engines without the need for major modifications.

  14. Proton exchange membrane fuel cells for electrical power generation on-board commercial airplanes.

    SciTech Connect (OSTI)

    Curgus, Dita Brigitte; Munoz-Ramos, Karina (Sandia National Laboratories, Albuquerque, NM); Pratt, Joseph William; Akhil, Abbas Ali (Sandia National Laboratories, Albuquerque, NM); Klebanoff, Leonard E.; Schenkman, Benjamin L. (Sandia National Laboratories, Albuquerque, NM)

    2011-05-01T23:59:59.000Z

    Deployed on a commercial airplane, proton exchange membrane fuel cells may offer emissions reductions, thermal efficiency gains, and enable locating the power near the point of use. This work seeks to understand whether on-board fuel cell systems are technically feasible, and, if so, if they offer a performance advantage for the airplane as a whole. Through hardware analysis and thermodynamic and electrical simulation, we found that while adding a fuel cell system using today's technology for the PEM fuel cell and hydrogen storage is technically feasible, it will not likely give the airplane a performance benefit. However, when we re-did the analysis using DOE-target technology for the PEM fuel cell and hydrogen storage, we found that the fuel cell system would provide a performance benefit to the airplane (i.e., it can save the airplane some fuel), depending on the way it is configured.

  15. Gas Turbine Emissions

    E-Print Network [OSTI]

    Frederick, J. D.

    technology developers and electric utilities will share emissions reductions in the coming era of pollution allowance trading is becoming prominent on the agendas of strategic planners at technology vendors and the electric power industry ??? ? (1...., "Authority to Construct for Badger Creek Limited," Kern County Air Pollution Control District, Bakersfield.. Ca., June 20, 1989. 3) Wark, K. and Warner, C. F., Air Pollution - Its Origin and Control, Harper and Row, New York, New York, 1976, pp. 453...

  16. Analysis of Emission Shapes

    E-Print Network [OSTI]

    P. Danielewicz

    2007-07-03T23:59:59.000Z

    Shapes of relative emission sources can be accessed by expanding shapes of correlations at low relative velocities in pair center of mass in Cartesian harmonics. Coefficients of expansion for correlations are related to the respective coefficients of expansion for the sources through one dimensional integral transforms involving properties of pair relative wavefunctions. The methodology is illustrated with analyses of NA49 and PHENIX correlation data.

  17. Studying the Proton "Radius" Puzzle with ?p Elastic Scattering

    E-Print Network [OSTI]

    R. Gilman; E. J. Downie; G. Ron; A. Afanasev; J. Arrington; O. Ates; F. Benmokhtar; J. Bernauer; E. Brash; W. J. Briscoe; K. Deiters; J. Diefenbach; C. Djalali; B. Dongwi; L. El Fassi; S. Gilad; K. Gnanvo; R. Gothe; D. Higinbotham; R. Holt; Y. Ilieva; H. Jiang; M. Kohl; G. Kumbartzki; J. Lichtenstadt; A. Liyanage; N. Liyanage; M. Meziane; Z. -E. Meziani; D. G. Middleton; P. Monaghan; K. E. Myers; C. Perdrisat; E. Piasetzsky; V. Punjabi; R. Ransome; D. Reggiani; P. Reimer; A. Richter; A. Sarty; E. Schulte; Y. Shamai; N. Sparveris; S. Strauch; V. Sulkosky; A. S. Tadepalli; M. Taragin; L. Weinstein

    2013-07-29T23:59:59.000Z

    The Proton Radius Puzzle is the inconsistency between the proton radius determined from muonic hydrogen and the proton radius determined from atomic hydrogen level transitions and ep elastic scattering. No generally accepted resolution to the Puzzle has been found. Possible solutions generally fall into one of three categories: the two radii are different due to novel beyond-standard-model physics, the two radii are different due to novel aspects of nucleon structure, and the two radii are the same, but there are underestimated uncertainties or other issues in the ep experiments. The MUon proton Scattering Experiment (MUSE) at the Paul Scherrer Institut is a simultaneous measurement of \\mu^+ p and e^+ p elastic scattering, as well as \\mu^- p and e^- p elastic scattering, which will allow a determination of the consistency of the \\mu p and the ep interactions. The differences between + and - charge scattering are sensitive to two-photon exchange effects, higher-order corrections to the scattering process. The slopes of the cross sections as Q^2 -> 0 determine the proton "radius". We plan to measure relative cross sections at a typical level of a few tenths of a percent, which should allow the proton radius to be determined at the level of ~0.01 fm, similar to previous ep measurements. The measurements will test several possible explanations of the proton radius puzzle, including some models of beyond-standard-model physics, some models of novel hadronic physics, and some issues in the radius extraction from scattering data.

  18. Proton radii of Be, B, and C isotopes

    E-Print Network [OSTI]

    Yoshiko Kanada-En'yo

    2014-11-04T23:59:59.000Z

    We investigate the neutron number $(N)$ dependence of root mean square radii of point proton distribution (proton radii) of Be, B, and C isotopes with the theoretical method of variation after spin-parity projection in the framework of antisymmetrized molecular dynamics (AMD). The proton radii in Be and B isotopes changes rapidly as $N$ increases, reflecting the cluster structure change along the isotope chains, whereas, those in C isotopes show a weak $N$ dependence because of the stable proton structure in nuclei with $Z=6$. In neutron-rich Be and B isotopes, the proton radii are remarkably increased by the enhancement of the two-center cluster structure in the prolately deformed neutron structure. We compare the $N$ dependence of the calculated proton radii with the experimental ones reduced from the charge radii determined by isotope shift and those deduced from the charge changing interaction cross section. It is found that the $N$ dependence of proton radii can be a probe to clarify enhancement and weakening of cluster structures.

  19. Proton transport and torque generation in rotary biomotors

    E-Print Network [OSTI]

    A. Yu. Smirnov; S. Savel'ev; L. G. Mourokh; Franco Nori

    2008-05-29T23:59:59.000Z

    We analyze the dynamics of rotary biomotors within a simple nano-electromechanical model, consisting of a stator part and a ring-shaped rotor having twelve proton-binding sites. This model is closely related to the membrane-embedded F$_0$ motor of adenosine triphosphate (ATP) synthase, which converts the energy of the transmembrane electrochemical gradient of protons into mechanical motion of the rotor. It is shown that the Coulomb coupling between the negative charge of the empty rotor site and the positive stator charge, located near the periplasmic proton-conducting channel (proton source), plays a dominant role in the torque-generating process. When approaching the source outlet, the rotor site has a proton energy level higher than the energy level of the site, located near the cytoplasmic channel (proton drain). In the first stage of this torque-generating process, the energy of the electrochemical potential is converted into potential energy of the proton-binding sites on the rotor. Afterwards, the tangential component of the Coulomb force produces a mechanical torque. We demonstrate that, at low temperatures, the loaded motor works in the shuttling regime where the energy of the electrochemical potential is consumed without producing any unidirectional rotation. The motor switches to the torque-generating regime at high temperatures, when the Brownian ratchet mechanism turns on. In the presence of a significant external torque, created by ATP hydrolysis, the system operates as a proton pump, which translocates protons against the transmembrane potential gradient. Here we focus on the F$_0$ motor, even though our analysis is applicable to the bacterial flagellar motor.

  20. Commissioning of output factors for uniform scanning proton beams

    SciTech Connect (OSTI)

    Zheng Yuanshui; Ramirez, Eric; Mascia, Anthony; Ding Xiaoning; Okoth, Benny; Zeidan, Omar; Hsi Wen; Harris, Ben; Schreuder, Andries N.; Keole, Sameer [ProCure Proton Therapy Center, 5901 West Memorial Road, Oklahoma City, Oklahoma 73142 (United States); ProCure Treatment Centers, 420 North Walnut Street, Bloomington, Indiana 47404 (United States); ProCure Proton Therapy Center, 5901 West Memorial Road, Oklahoma City, Oklahoma 73142 (United States)

    2011-04-15T23:59:59.000Z

    Purpose: Current commercial treatment planning systems are not able to accurately predict output factors and calculate monitor units for proton fields. Patient-specific field output factors are thus determined by either measurements or empirical modeling based on commissioning data. The objective of this study is to commission output factors for uniform scanning beams utilized at the ProCure proton therapy centers. Methods: Using water phantoms and a plane parallel ionization chamber, the authors first measured output factors with a fixed 10 cm diameter aperture as a function of proton range and modulation width for clinically available proton beams with ranges between 4 and 31.5 cm and modulation widths between 2 and 15 cm. The authors then measured the output factor as a function of collimated field size at various calibration depths for proton beams of various ranges and modulation widths. The authors further examined the dependence of the output factor on the scanning area (i.e., uncollimated proton field), snout position, and phantom material. An empirical model was developed to calculate the output factor for patient-specific fields and the model-predicted output factors were compared to measurements. Results: The output factor increased with proton range and field size, and decreased with modulation width. The scanning area and snout position have a small but non-negligible effect on the output factors. The predicted output factors based on the empirical modeling agreed within 2% of measurements for all prostate treatment fields and within 3% for 98.5% of all treatment fields. Conclusions: Comprehensive measurements at a large subset of available beam conditions are needed to commission output factors for proton therapy beams. The empirical modeling agrees well with the measured output factor data. This investigation indicates that it is possible to accurately predict output factors and thus eliminate or reduce time-consuming patient-specific output measurements for proton treatments.

  1. Measurement of the Proton's Neutral Weak Magnetic Form Factor

    E-Print Network [OSTI]

    B. Mueller; D. H. Beck; E. J. Beise; E. Candell; L. Cardman; R. Carr; R. C. DiBari; G. Dodson; K. Dow; F. Duncan; M. Farkhondeh; B. W. Filippone; T. Forest; H. Gao; W. Korsch; S. Kowalski; A. Lung; R. D. McKeown; R. Mohring; J. Napolitano; D. Nilsson; M. Pitt; N. Simicevic; B. Terburg; S. P. Wells

    1997-02-26T23:59:59.000Z

    We report the first measurement of the parity-violating asymmetry in elastic electron scattering from the proton. The asymmetry depends on the neutral weak magnetic form factor of the proton which contains new information on the contribution of strange quark-antiquark pairs to the magnetic moment of the proton. We obtain the value $G_M^Z= 0.34 \\pm 0.09 \\pm 0.04 \\pm 0.05$ n.m. at $Q^2=0.1$ (GeV/c)${}^2$.

  2. Retention and switching kinetics of protonated gate field effect transistors

    SciTech Connect (OSTI)

    DEVINE,R.A.B.; HERRERA,GILBERT V.

    2000-05-23T23:59:59.000Z

    The switching and memory retention time has been measured in 50 {micro}m gatelength pseudo-non-volatile memory MOSFETS containing, protonated 40 nm gate oxides. Times of the order of 3.3 seconds are observed for fields of 3 MV cm{sup {minus}1}. The retention time with protons placed either at the gate oxide/substrate or gate oxide/gate electrode interfaces is found to better than 96{percent} after 5,000 seconds. Measurement of the time dependence of the source-drain current during switching provides clear evidence for the presence of dispersive proton transport through the gate oxide.

  3. Retention and Switching Kinetics of Protonated Gate Field Effect Transistors

    SciTech Connect (OSTI)

    DEVINE,R.A.B.; HERRERA,GILBERT V.

    2000-06-27T23:59:59.000Z

    The switching and memory retention time has been measured in 50 {micro}m gatelength pseudo-non-volatile memory MOSFETs containing, protonated 40 nm gate oxides. Times of the order of 3.3 seconds are observed for fields of 3 MV cm{sup {minus}1}. The retention time with protons placed either at the gate oxide/substrate or gate oxide/gate electrode interfaces is found to better than 96% after 5,000 seconds. Measurement of the time dependence of the source-drain current during switching provides clear evidence for the presence of dispersive proton transport through the gate oxide.

  4. Improved proton computed tomography by dual modality image reconstruction

    SciTech Connect (OSTI)

    Hansen, David C., E-mail: dch@ki.au.dk; Bassler, Niels [Experimental Clinical Oncology, Aarhus University, 8000 Aarhus C (Denmark)] [Experimental Clinical Oncology, Aarhus University, 8000 Aarhus C (Denmark); Petersen, Jørgen Breede Baltzer [Medical Physics, Aarhus University Hospital, 8000 Aarhus C (Denmark)] [Medical Physics, Aarhus University Hospital, 8000 Aarhus C (Denmark); Sørensen, Thomas Sangild [Computer Science, Aarhus University, 8000 Aarhus C, Denmark and Clinical Medicine, Aarhus University, 8200 Aarhus N (Denmark)] [Computer Science, Aarhus University, 8000 Aarhus C, Denmark and Clinical Medicine, Aarhus University, 8200 Aarhus N (Denmark)

    2014-03-15T23:59:59.000Z

    Purpose: Proton computed tomography (CT) is a promising image modality for improving the stopping power estimates and dose calculations for particle therapy. However, the finite range of about 33 cm of water of most commercial proton therapy systems limits the sites that can be scanned from a full 360° rotation. In this paper the authors propose a method to overcome the problem using a dual modality reconstruction (DMR) combining the proton data with a cone-beam x-ray prior. Methods: A Catphan 600 phantom was scanned using a cone beam x-ray CT scanner. A digital replica of the phantom was created in the Monte Carlo code Geant4 and a 360° proton CT scan was simulated, storing the entrance and exit position and momentum vector of every proton. Proton CT images were reconstructed using a varying number of angles from the scan. The proton CT images were reconstructed using a constrained nonlinear conjugate gradient algorithm, minimizing total variation and the x-ray CT prior while remaining consistent with the proton projection data. The proton histories were reconstructed along curved cubic-spline paths. Results: The spatial resolution of the cone beam CT prior was retained for the fully sampled case and the 90° interval case, with the MTF = 0.5 (modulation transfer function) ranging from 5.22 to 5.65?linepairs/cm. In the 45° interval case, the MTF = 0.5 dropped to 3.91?linepairs/cm For the fully sampled DMR, the maximal root mean square (RMS) error was 0.006 in units of relative stopping power. For the limited angle cases the maximal RMS error was 0.18, an almost five-fold improvement over the cone beam CT estimate. Conclusions: Dual modality reconstruction yields the high spatial resolution of cone beam x-ray CT while maintaining the improved stopping power estimation of proton CT. In the case of limited angles, the use of prior image proton CT greatly improves the resolution and stopping power estimate, but does not fully achieve the quality of a 360° proton CT scan.

  5. Self-Excitation and Feedback Cooling of an Isolated Proton

    SciTech Connect (OSTI)

    Guise, N.; DiSciacca, J.; Gabrielse, G. [Department of Physics, Harvard University, Cambridge, Massachusetts 02138 (United States)

    2010-04-09T23:59:59.000Z

    The first one-proton self-excited oscillator (SEO) and one-proton feedback cooling are demonstrated. In a Penning trap with a large magnetic gradient, the SEO frequency is resolved to the high precision needed to detect a one-proton spin flip. This is after undamped magnetron motion is sideband cooled to a 14 mK theoretical limit, and despite random frequency shifts (typically larger than those from a spin flip) that take place every time sideband cooling is applied. The observations open a possible path towards a million-fold improved comparison of the p and p magnetic moments.

  6. Proton Profile Function at 52.8 GeV

    E-Print Network [OSTI]

    Geovanna L. P. Silva; Marcio J. Menon; Regina F. Avila

    2008-02-12T23:59:59.000Z

    We present the results of a novel model-independent fit to elastic proton-proton differential cross section data at $\\sqrt s$ = 52.8 GeV. Taking into account the error propagation from the fit parameters, we determine the scattering amplitude in the impact parameter space (the proton profile function) and its statistical uncertainty region. We show that both the real and imaginary parts of the profile are consistent with two dynamical contributions, one from a central dense region, up to roughly 1 fm and another from a peripheral evanescent region from 1 to 3 fm.

  7. Mixed anion materials and compounds for novel proton conducting membranes

    DOE Patents [OSTI]

    Poling, Steven Andrew; Nelson, Carly R.; Martin, Steve W.

    2006-09-05T23:59:59.000Z

    The present invention provides new amorphous or partially crystalline mixed anion chalcogenide compounds for use in proton exchange membranes which are able to operate over a wide variety of temperature ranges, including in the intermediate temperature range of about 100 .degree. C. to 300.degree. C., and new uses for crystalline mixed anion chalcogenide compounds in such proton exchange membranes. In one embodiment, the proton conductivity of the compounds is between about 10.sup.-8 S/cm and 10.sup.-1 S/cm within a temperature range of between about -60 and 300.degree. C. and a relative humidity of less than about 12%..

  8. Direct mass measurements beyond the proton drip-line

    E-Print Network [OSTI]

    C. Rauth; D. Ackermann; K. Blaum; M. Block; A. Chaudhuri; S. Eliseev; R. Ferrer; D. Habs; F. Herfurth; F. P. Hessberger; S. Hofmann; H. -J. Kluge; G. Maero; A. Martin; G. Marx; M. Mukherjee; J. B. Neumayr; W. R. Plass; W. Quint; S. Rahaman; D. Rodriguez; C. Scheidenberger; L. Schweikhard; P. G. Thirolf; G. Vorobjev; C. Weber; Z. Di

    2007-01-22T23:59:59.000Z

    First on-line mass measurements were performed at the SHIPTRAP Penning trap mass spectrometer. The masses of 18 neutron-deficient isotopes in the terbium-to-thulium region produced in fusion-evaporation reactions were determined with relative uncertainties of about $7\\cdot 10^{-8}$, nine of them for the first time. Four nuclides ($^{144, 145}$Ho and $^{147, 148}$Tm) were found to be proton-unbound. The implication of the results on the location of the proton drip-line is discussed by analyzing the one-proton separation energies.

  9. Gluonic Spin Contribution to Proton Spin at NLO

    SciTech Connect (OSTI)

    Casey, Andrew [CSSM, School of Chemistry and Physics, University of Adelaide, Adelaide SA 5005 (Australia)

    2011-05-24T23:59:59.000Z

    In 1988, when the EMC results showed that the quarks had a much smaller contribution to the spin of the proton than previously thought, the 'Proton Spin Crisis' began. Since then, considerable effort has been directed into discovering the main contributors to proton spin and how much each contributes. One such contributor is the gluonic spin component. QCD NLO evolution equations are combined with boundary conditions obtained from heavy quark decoupling expressions to evolve the equations from infinity to the mass of the charm quark in order to determine the gluonic spin contribution.

  10. Proton Channel Orientation in Block-Copolymer Electrolyte Membranes

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible forPortsmouth/Paducah47,193.70 HgPromisingProtectingSciTech ConnectProtonProtonProton

  11. Partnerships to continue moving toward zero emissions

    E-Print Network [OSTI]

    California at Davis, University of

    Partnerships to continue moving toward zero emissions Zero Emission transportation goals Zero Emission MAP makes available technical assistance to states and cities to support the growth of zero emission mobility markets. 1 Research shows

  12. Distributed Energy Resources for Carbon Emissions Mitigation

    E-Print Network [OSTI]

    Firestone, Ryan; Marnay, Chris

    2008-01-01T23:59:59.000Z

    Distributed Energy Resource Technology Characterizations. ”ABORATORY Distributed Energy Resources for Carbon Emissions5128 Distributed Energy Resources for Carbon Emissions

  13. Measurement and Characterization of Unregulated Emissions from...

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

    & Publications Ethanol Effects on Lean-Burn and Stoichiometric GDI Emissions Measurement and Characterization of Unregulated Emissions from Advanced Technologies...

  14. Bremsstrahlung radiation in the deuteron - proton collision

    E-Print Network [OSTI]

    J. Przerwa

    2005-01-06T23:59:59.000Z

    Despite the fact that Bremsstrahlung radiation has been observed many years ago, it is still the subject of interest of many theoretical and experimental groups. Due to the high sensitivity of the NN --> NNgamma reaction to the nucleon-nucleon potential, Bremsstrahlung radiation is used as a tool to investigate details of the nucleon-nucleon interaction. Such investigations can be performed at the cooler synchrotron COSY in the Research Centre Juelich, by dint of the COSY-11 detection system. For the first time at the COSY--11 experiment signals from gamma - quanta were observed in the time-of-flight distribution of neutral particles measured with the neutral particle detector. In this thesis the results of the identification of Bremsstrahlung radiation emitted via the dp --> dpgamma reaction in data taken with a proton target and a deuteron beam are presented and discussed. The time resolution of the neutral particle detector and its timing calibration are crucial for the identification of the dp --> dpgamma reaction. Therefore, methods of determining the relative timing between individual modules - constituting the neutron detector - and of the general time offset with respect to the other detector components are described. Furthermore the accuracy of the momentum determination of the registered neutron which defines the precision of the event reconstruction was extracted from the data.

  15. WHITE PAPER ON PROTON - NUCLEUS COLLISONS.

    SciTech Connect (OSTI)

    ARONSON,S.H.; PENG,J.C.

    2001-03-01T23:59:59.000Z

    The role of proton-nucleus (p-A) collisions in the study of strong interactions has a long history. It has been an important testing ground for QCD. At RHIC p-A studies have been recognized since the beginning as important elements of the program. These include so-called baseline measurements in cold nuclear matter, essential (along with p-p studies) to a systematic study of QCD at high temperatures and densities in the search for the quark gluon plasma. Also accessible is a study of QCD in the small x (parton saturation) regime, complementary to physics accessible in high-energy e-p and e-A collisions. The role of p-A physics at RHIC was reviewed and brought into sharp focus at a workshop conducted in October 2000 at BNL; the agenda is shown in Appendix 1. This document summarizes the case for p-A at RHIC during the period covered by the next Nuclear Physics Long Range Plan. In subsequent sections we cover the Physics Issues, Experiment Run Plans and Schedule, Detector Upgrade Issues, and Machine Issues & Upgrades.

  16. High intensity electron cyclotron resonance proton source for low energy high intensity proton accelerator

    SciTech Connect (OSTI)

    Roychowdhury, P.; Chakravarthy, D. P. [Accelerator and Pulse Power Division, Bhabha Atomic Research Centre, Mumbai 400085 (India)

    2009-12-15T23:59:59.000Z

    Electron cyclotron resonance (ECR) proton source at 50 keV, 50 mA has been designed, developed, and commissioned for the low energy high intensity proton accelerator (LEHIPA). Plasma characterization of this source has been performed. ECR plasma was generated with 400-1100 W of microwave power at 2.45 GHz, with hydrogen as working gas. Microwave was fed in the plasma chamber through quartz window. Plasma density and temperature was studied under various operating conditions, such as microwave power and gas pressure. Langmuir probe was used for plasma characterization using current voltage variation. The typical hydrogen plasma density and electron temperature measured were 7x10{sup 11} cm{sup -3} and 6 eV, respectively. The total ion beam current of 42 mA was extracted, with three-electrode extraction geometry, at 40 keV of beam energy. The extracted ion current was studied as a function of microwave power and gas pressure. Depending on source pressure and discharge power, more than 30% total gas efficiency was achieved. The optimization of the source is under progress to meet the requirement of long time operation. The source will be used as an injector for continuous wave radio frequency quadrupole, a part of 20 MeV LEHIPA. The required rms normalized emittance of this source is less than 0.2 {pi} mm mrad. The simulated value of normalized emittance is well within this limit and will be measured shortly. This paper presents the study of plasma parameters, first beam results, and the status of ECR proton source.

  17. Fabrication of Annealed Proton-Exchanged Waveguides for Vertical Integration 

    E-Print Network [OSTI]

    Webb, Jacob Douglas

    2011-08-08T23:59:59.000Z

    There is a drive for improving the surface uniformity of optical waveguide devices in the photonics lab. This report focuses on the exploration of annealed proton exchange (APE) waveguide fabrication on lithium niobate crystal as a method...

  18. Comparison of proton and neutron carrier removal rates

    SciTech Connect (OSTI)

    Pease, R.L.; Enlow, E.W.; Dinger, G.L.; Marshall, P.

    1987-12-01T23:59:59.000Z

    Displacement damage induced carrier removal rates for proton irradiations in the energy range 10-175 MeV were compared to 1 MeV equivalent neutrons using power MOSFETs as a test vehicle. The results showed that, within experimental error, the degradation mechanisms were qualitatively similar and the ratio of proton to neutron carrier removal rates as a function of proton energy correlate with a calculation based on nonionization energy loss in silicon. For exposures under junction bias, p-type silicon was found to have a smaller carrier removal rate for both proton and neutron irradiations, whereas, for n-type silicon, junction bias had little effect on the carrier removal rate.

  19. The shape of the proton at high energies

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

    Schlichting, Soren; Schenke, Bjorn

    2014-12-01T23:59:59.000Z

    We present first calculations of the fluctuating gluon distribution in a proton as a function of impact parameter and rapidity employing the functional Langevin form of the JIMWLK renormalization group equation. We demonstrate that when including effects of confinement by screening the long range Coulomb field of the color charges, the evolution is unitary. The large-x structure of the proton, characterized by the position of three valence quarks, retains an effect on the proton shape down to very small values of x. We determine the dipole scattering amplitude as a function of impact parameter and dipole size and extract themore »rapidity evolution of the saturation scale and the proton radius.« less

  20. Nuclear binding energies and empirical proton-neutron interactions

    SciTech Connect (OSTI)

    Fu, G. J. [Department of Physics, Shanghai Jiao Tong University, Shanghai 200240 (China); Jiang Hui [Department of Physics, Shanghai Jiao Tong University, Shanghai 200240 (China); School of Arts and Science, Shanghai Maritime University, Shanghai 200135 (China); Zhao, Y. M. [Department of Physics, Shanghai Jiao Tong University, Shanghai 200240 (China); Center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Accelerator, Lanzhou 730000 (China); CCAST, World Laboratory, Post Office Box 8730, Beijing 100080 (China); Pittel, S. [Bartol Research Institute and Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716 (United States); Arima, A. [Department of Physics, Shanghai Jiao Tong University, Shanghai 200240 (China); Science Museum, Japan Science Foundation, 2-1 Kitanomaru-koen, Chiyoda-ku, Tokyo 102-0091 (Japan)

    2010-09-15T23:59:59.000Z

    By using an exponential function to simulate the residual proton-neutron interaction between valence nucleons, we derive a new set of local mass formulas that are competitive with the Garvey-Kelson mass relations for relating neighboring nuclear masses.

  1. Fabrication of Annealed Proton-Exchanged Waveguides for Vertical Integration

    E-Print Network [OSTI]

    Webb, Jacob Douglas

    2011-08-08T23:59:59.000Z

    There is a drive for improving the surface uniformity of optical waveguide devices in the photonics lab. This report focuses on the exploration of annealed proton exchange (APE) waveguide fabrication on lithium niobate crystal as a method...

  2. RADIATION DAMAGE TO BSCCO-2223 FROM 50 MEV PROTONS

    E-Print Network [OSTI]

    Zeller, A.F.; Ronningen, R.M.; Godeke, A.; Heilbronn, L.H.; McMahan-Norris, P.; Gupta, R.

    2007-01-01T23:59:59.000Z

    RADIATION DAMAGE TO BSCCO-2223 FROM 50 MEV PROTONS A. F.BSCCO-2223. Radiation damage. INTRODUCTION The magnets incomponents be resistant to damage. One solution [1] is to

  3. FNAL Proton Source High Intensity Operations and Beam Loss Control

    E-Print Network [OSTI]

    Garcia, F G

    2014-01-01T23:59:59.000Z

    The 40-year-old Fermilab Proton Source machines, constituted by the Pre-Injector, Linac and the synchrotron Booster, have been the workhorse of the Fermi National Accelerator Laboratory (Fermilab). During this time, the High Energy Physics Program has demanded an increase in proton throughput, especially during the past decade with the beginning of the neutrino program at Fermilab. In order to achieve a successful program, major upgrades and changes were made in Booster. Once again, the Proton Source has been charged to double their beam throughput, while maintain the present residual activation levels, to meet the laboratory Intensity Frontier program goals until new machines are built and operational to replace the Proton Source machines. This paper discusses the present performance of Booster and the plans involved in reaching even higher intensities.

  4. Energetics and Dynamics of the Fragmentation Reactions of Protonated...

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

    via the loss of CH3SOH (64Da), and (ii) preferential cleavage of the amide bond C-terminal to aspartic acid. The role of proton mobility on these selective bond cleavage...

  5. Proton Radiography at Los Alamos National Laboratory (pRad)

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

    pRad User Program pRad-uo@lanl.gov P-25 Subatomic Physics P-Division LANSCE pRad logo Los Alamos National Laboratory has used high energy protons as a probe in flash...

  6. Proton lifetime bounds from chirally symmetric lattice QCD

    E-Print Network [OSTI]

    Y. Aoki; P. Boyle; P. Cooney; L. Del Debbio; R. Kenway; C. M. Maynard; A. Soni; R. Tweedie

    2008-06-05T23:59:59.000Z

    We present results for the matrix elements relevant for proton decay in Grand Unified Theories (GUTs). The calculation is performed at a fixed lattice spacing a^{-1}=1.73(3) GeV using 2+1 flavors of domain wall fermions on lattices of size 16^3\\times32 and 24^3\\times64 with a fifth dimension of length 16. We use the indirect method which relies on an effective field theory description of proton decay, where we need to estimate the low energy constants, \\alpha = -0.0112(25) GeV^3 and \\beta = 0.0120(26) GeV^3. We relate these low energy constants to the proton decay matrix elements using leading order chiral perturbation theory. These can then be combined with experimental bounds on the proton lifetime to bound parameters of individual GUTs.

  7. Workshop on acceleration of polarized protons: summary report

    SciTech Connect (OSTI)

    Lee, Y.Y.; Terwilliger, K.M.

    1982-01-01T23:59:59.000Z

    The workshop sessions concentrated on polarized protons in circular accelerators and storage rings. Topics such as polarized electrons were discussed only when the subject was relevant to proton phenomena. Of major interest was the possible applicability of the new idea of spin matching for crossing depolarizing resonances. On the experimental side, some remarkable new data were presented by the SATURNE II Group. They have successfully crossed both intrinsic and imperfection depolarizing resonances by the spin flip method with minimal depolarization-the first group to do so. They also obtained some results which apparently cannot be explained with our present understanding of spin phenomena. The workshop concluded that more experimental measurements are needed to understand the physics and that such studies would be very important for the future acceleration of polarized protons at KEK and the AGS. The workshop included status reports from the four laboratories which have programs of polarized particle acceleration--or approved projects to accelerate polarized protons.

  8. Predicted Impacts of Proton Temperature Anisotropy on Solar Wind Turbulence

    E-Print Network [OSTI]

    Klein, Kristopher G

    2015-01-01T23:59:59.000Z

    Particle velocity distributions measured in the weakly collisional solar wind are frequently found to be non-Maxwellian, but how these non-Maxwellian distributions impact the physics of plasma turbulence in the solar wind remains unanswered. Using numerical solutions of the linear dispersion relation for a collisionless plasma with a bi-Maxwellian proton velocity distribution, we present a unified framework for the four proton temperature anisotropy instabilities, identifying the associated stable eigenmodes, highlighting the unstable region of wavevector space, and presenting the properties of the growing eigenfunctions. Based on physical intuition gained from this framework, we address how the proton temperature anisotropy impacts the nonlinear dynamics of the \\Alfvenic fluctuations underlying the dominant cascade of energy from large to small scales and how the fluctuations driven by proton temperature anisotropy instabilities interact nonlinearly with each other and with the fluctuations of the large-scal...

  9. Polarized proton acceleration at the BNL AGS, 1988

    SciTech Connect (OSTI)

    Ahrens, L.

    1988-01-01T23:59:59.000Z

    The present status of the polarized proton acceleration at the Brookhaven AGS is described. Some details regarding the tune-up and performance during the December 1987-January 1988 physics run are given. 2 refs., 4 figs.

  10. Charge Symmetry Breaking and Parity Violating Electron-Proton Scattering

    E-Print Network [OSTI]

    Michael Wagman; Gerald A. Miller

    2014-12-16T23:59:59.000Z

    Charge symmetry breaking contributions to the proton's neutral weak form factors must be understood in order for future measurements of parity violating electron-proton scattering to be definitively interpreted as evidence of proton strangeness. We calculate these charge symmetry breaking form factor contributions using chiral perturbation theory with resonance saturation estimates for unknown low-energy constants. The uncertainty of the leading-order resonance saturation estimates is reduced by incorporating nuclear physics constraints. Higher-order contributions are investigated through phenomenological vertex form factors. We predict that charge symmetry breaking form factor contributions are an order of magnitude larger than expected from naive dimensional analysis but are still an order of magnitude smaller than current experimental bounds on proton strangeness. This is consistent with previous calculations using chiral perturbation theory with resonance saturation.

  11. Reverse convection and cusp proton aurora: Cluster, polar and image observation

    E-Print Network [OSTI]

    California at Berkeley, University of

    Reverse convection and cusp proton aurora: Cluster, polar and image observation Q.-G. Zong a,b,*, TT) at Earth. Cusp proton aurora was caused by the leading phase of the CME. Cusp proton aurora generally of the cusp proton aurora shifted about 30° from dawnside to duskside when IMF By changed from À10 to 5 n

  12. CERN 6 Tesla superconducting persistent dipole/Filming an experiment/Synchrotron radiation from protons

    E-Print Network [OSTI]

    1979-01-01T23:59:59.000Z

    CERN 6 Tesla superconducting persistent dipole/Filming an experiment/Synchrotron radiation from protons

  13. Proton charge radius and the perturbative quantum electrodynamics Krzysztof Pachucki and Krzysztof A. Meissner

    E-Print Network [OSTI]

    Pachucki, Krzysztof

    Proton charge radius and the perturbative quantum electrodynamics Krzysztof Pachucki and Krzysztof that the proton charge radius conundrum can be resolved by weakening the assumption of pertur- bative formulation of quantum electrodynamics within the proton. PACS numbers: 12.20.-m, 13.60.-r, 31.30.jr The proton radius

  14. SCIPP 06/04 1 Prototype Tracking Studies for Proton CT

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    SCIPP 06/04 1 Prototype Tracking Studies for Proton CT Nate Blumenkrantz, Jason Feldt, Jason the feasibility of proton computed tomography, the most likely path (MLP) of protons inside an absorber resolution. The locations of 200 MeV protons were measured at three different absorber depth of PMMA (3.75, 6

  15. Subauroral proton spots visualize the Pc1 source A. G. Yahnin,1

    E-Print Network [OSTI]

    California at Berkeley, University of

    Subauroral proton spots visualize the Pc1 source A. G. Yahnin,1 T. A. Yahnina,1 and H. U. Frey2 observations from the IMAGE spacecraft revealed a new type of proton aurora ­ subauroral proton spots, which map onto the vicinity of the plasmapause. It has been suggested that this proton aurora is produced

  16. Transport properties and fuel cell performance of sulfonated poly(imide) proton exchange membranes

    E-Print Network [OSTI]

    Transport properties and fuel cell performance of sulfonated poly(imide) proton exchange membranes for their performance as proton exchange membranes in direct methanol fuel cells (DMFC). The proton to methanol of chemical fuels, such as methanol [3]. For portable applications, proton exchange membrane fuel cells

  17. Positron Emission Tomography (PET)

    DOE R&D Accomplishments [OSTI]

    Welch, M. J.

    1990-01-00T23:59:59.000Z

    Positron emission tomography (PET) assesses biochemical processes in the living subject, producing images of function rather than form. Using PET, physicians are able to obtain not the anatomical information provided by other medical imaging techniques, but pictures of physiological activity. In metaphoric terms, traditional imaging methods supply a map of the body's roadways, its, anatomy; PET shows the traffic along those paths, its biochemistry. This document discusses the principles of PET, the radiopharmaceuticals in PET, PET research, clinical applications of PET, the cost of PET, training of individuals for PET, the role of the United States Department of Energy in PET, and the futures of PET.

  18. Acoustic emission intrusion detector

    DOE Patents [OSTI]

    Carver, Donald W. (Knoxville, TN); Whittaker, Jerry W. (Knoxville, TN)

    1980-01-01T23:59:59.000Z

    An intrusion detector is provided for detecting a forcible entry into a secured structure while minimizing false alarms. The detector uses a piezoelectric crystal transducer to sense acoustic emissions. The transducer output is amplified by a selectable gain amplifier to control the sensitivity. The rectified output of the amplifier is applied to a Schmitt trigger circuit having a preselected threshold level to provide amplitude discrimination. Timing circuitry is provided which is activated by successive pulses from the Schmitt trigger which lie within a selected time frame for frequency discrimination. Detected signals having proper amplitude and frequency trigger an alarm within the first complete cycle time of a detected acoustical disturbance signal.

  19. Single shot cell irradiations with laser-driven protons

    SciTech Connect (OSTI)

    Humble, N.; Schmid, T. E.; Zlobinskaya, O.; Wilkens, J. J. [Department of Radiation Oncology, Klinikum rechts der Isar, Technische Universität München (Germany)] [Department of Radiation Oncology, Klinikum rechts der Isar, Technische Universität München (Germany); Allinger, K.; Hilz, P.; Ma, W.; Reinhardt, S. [Physics Department, Ludwig-Maximilians-Universität München (Germany)] [Physics Department, Ludwig-Maximilians-Universität München (Germany); Bin, J.; Kiefer, D.; Schreiber, J. [Max Planck Institute of Quantum Optics, Garching (Germany)] [Max Planck Institute of Quantum Optics, Garching (Germany); Drexler, G. A.; Friedl, A. [Department of Radiation Oncology, Ludwig-Maximilians-Universität München (Germany)] [Department of Radiation Oncology, Ludwig-Maximilians-Universität München (Germany)

    2013-07-26T23:59:59.000Z

    Ion beams are relevant for radiobiological studies in basic research and for application in tumor therapy. Here we present a method to generate nanosecond proton bunches with single shot doses of up to 7 Gray by a tabletop high-power laser. Although in their infancy, laser-ion accelerators allow studying fast radiobiological processes at small-scale laboratories as exemplarily demonstrated by measurements of the relative biological effectiveness of protons in human tumor cells.

  20. Physical and biological factors determining the effective proton range

    SciTech Connect (OSTI)

    Grün, Rebecca [Department of Biophysics, GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt 64291 (Germany) [Department of Biophysics, GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt 64291 (Germany); Institute of Medical Physics and Radiation Protection, University of Applied Sciences Gießen, Gießen 35390 (Germany); Medical Faculty of Philipps-University Marburg, Marburg 35032 (Germany); Friedrich, Thomas; Krämer, Michael; Scholz, Michael [Department of Biophysics, GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt 64291 (Germany)] [Department of Biophysics, GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt 64291 (Germany); Zink, Klemens [Institute of Medical Physics and Radiation Protection, University of Applied Sciences Gießen, Gießen 35390, Germany and Department of Radiotherapy and Radiation Oncology, University Medical Center Giessen and Marburg, Marburg 35043 (Germany)] [Institute of Medical Physics and Radiation Protection, University of Applied Sciences Gießen, Gießen 35390, Germany and Department of Radiotherapy and Radiation Oncology, University Medical Center Giessen and Marburg, Marburg 35043 (Germany); Durante, Marco [Department of Biophysics, GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt 64291, Germany and Department of Condensed Matter Physics, Darmstadt University of Technology, Darmstadt 64289 (Germany)] [Department of Biophysics, GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt 64291, Germany and Department of Condensed Matter Physics, Darmstadt University of Technology, Darmstadt 64289 (Germany); Engenhart-Cabillic, Rita [Medical Faculty of Philipps-University Marburg, Marburg 35032, Germany and Department of Radiotherapy and Radiation Oncology, University Medical Center Giessen and Marburg, Marburg 35043 (Germany)] [Medical Faculty of Philipps-University Marburg, Marburg 35032, Germany and Department of Radiotherapy and Radiation Oncology, University Medical Center Giessen and Marburg, Marburg 35043 (Germany)

    2013-11-15T23:59:59.000Z

    Purpose: Proton radiotherapy is rapidly becoming a standard treatment option for cancer. However, even though experimental data show an increase of the relative biological effectiveness (RBE) with depth, particularly at the distal end of the treatment field, a generic RBE of 1.1 is currently used in proton radiotherapy. This discrepancy might affect the effective penetration depth of the proton beam and thus the dose to the surrounding tissue and organs at risk. The purpose of this study was thus to analyze the impact of a tissue and dose dependent RBE of protons on the effective range of the proton beam in comparison to the range based on a generic RBE of 1.1.Methods: Factors influencing the biologically effective proton range were systematically analyzed by means of treatment planning studies using the Local Effect Model (LEM IV) and the treatment planning software TRiP98. Special emphasis was put on the comparison of passive and active range modulation techniques.Results: Beam energy, tissue type, and dose level significantly affected the biological extension of the treatment field at the distal edge. Up to 4 mm increased penetration depth as compared to the depth based on a constant RBE of 1.1. The extension of the biologically effective range strongly depends on the initial proton energy used for the most distal layer of the field and correlates with the width of the distal penumbra. Thus, the range extension, in general, was more pronounced for passive as compared to active range modulation systems, whereas the maximum RBE was higher for active systems.Conclusions: The analysis showed that the physical characteristics of the proton beam in terms of the width of the distal penumbra have a great impact on the RBE gradient and thus also the biologically effective penetration depth of the beam.

  1. Proton-neutron pairing correlations in the nuclear shell model

    E-Print Network [OSTI]

    Lei Yang; S. Pittel; B. Thakur; N. Sandulescu; A. Poves; Yu-Min Zhao

    2010-06-16T23:59:59.000Z

    A shell-model study of proton-neutron pairing in f - p shell nuclei using a parametrized hamiltonian that includes deformation and spin-orbit effects as well as isoscalar and isovector pairing is reported. By working in a shell-model framework we are able to assess the role of the various modes of proton-neutron pairing in the presence of nuclear deformation without violating symmetries. Results are presented for $^{44}$Ti, $^{46}$Ti and $^{48}$Cr.

  2. Modeling Uranium-Proton Ion Exchange in Biosorption

    E-Print Network [OSTI]

    Volesky, Bohumil

    seaweed biomass was used to remove the heavy metal uranium from the aqueous solution. Uranium biosorptionModeling Uranium-Proton Ion Exchange in Biosorption J I N B A I Y A N G A N D B O H U M I L V O L E, Quebec, Canada H3A 2B2 Biosorption of uranium metal ions by a nonliving protonated Sargassum fluitans

  3. RADIATION DAMAGE TO BSCCO-2223 FROM 50 MEV PROTONS

    SciTech Connect (OSTI)

    Zeller, A.F.; Ronningen, R.M.; Godeke, Arno; Heibronn, L.H; McMahan-Norris, P.; Gupta, R.

    2007-11-01T23:59:59.000Z

    The use of HTS materials in high radiation environments requires that the superconducting properties remain constant up to a radiation high dose. BSCCO-2223 samples from two manufacturers were irradiated with 50 MeV protons at fluences of up to 5 x 10{sup 17} protons/cm{sup 2}. The samples lost approximately 75% of their pre-irradiation I{sub c}. This compares with Nb{sub 3}Sn, which loses about 50% at the same displacements per atom.

  4. Proton induced fission of 181-Ta at relativistic energies

    E-Print Network [OSTI]

    Y. Ayyad; J. Benlliure; E. Casarejos; H. Álvarez-Pol; A. Bacquias; A. Boudard; M. Caamaño; T. Enqvist; V. Föhr; A. Keli?-Heil; K. Kezzar; S. Leray; C. Paradela; D. Pérez-Loureiro; R. Pleska?; D. Tarrío

    2012-03-07T23:59:59.000Z

    Total fission cross sections of 181-Ta induced by protons at different relativistic energies have been measured at GSI, Darmstadt. The inverse kinematics technique used together with a dedicated set-up, made it possible to determine these cross sections with high accuracy. The new data obtained in this experiment will contribute to the understanding of the fission process at high excitation energies. The results are compared with data from previous experiments and systematics for proton-induced fission cross sections.

  5. The Spin of The Proton: Looking Back and Looking Forward

    SciTech Connect (OSTI)

    Ji Xiangdong [Department of Physics, University of Maryland, College Park, MD 20742 (United States)

    2006-11-17T23:59:59.000Z

    The physics of the spin structure of the proton is reviewed. The EMC experiment and the follow-up ones have shown that the quark spin carries about 1/4 of the spin of the proton. The suspected large gluon polarization is under intense studies with various experimental tools. Generalized parton distributions probed in deeply-virtual Compton scattering allows reconstruction of quark orbital angular momentum.

  6. Network analysis of proton transfer in liquid water

    SciTech Connect (OSTI)

    Shevchuk, Roman; Rao, Francesco, E-mail: francesco.rao@frias.uni-freiburg.de [Freiburg Institute for Advanced Studies, School of Soft Matter Research, Freiburg im Breisgau (Germany); Agmon, Noam [Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem (Israel)

    2014-06-28T23:59:59.000Z

    Proton transfer in macromolecular systems is a fascinating yet elusive process. In the last ten years, molecular simulations have shown to be a useful tool to unveil the atomistic mechanism. Notwithstanding, the large number of degrees of freedom involved make the accurate description of the process very hard even for the case of proton diffusion in bulk water. Here, multi-state empirical valence bond molecular dynamics simulations in conjunction with complex network analysis are applied to study proton transfer in liquid water. Making use of a transition network formalism, this approach takes into account the time evolution of several coordinates simultaneously. Our results provide evidence for a strong dependence of proton transfer on the length of the hydrogen bond solvating the Zundel complex, with proton transfer enhancement as shorter bonds are formed at the acceptor site. We identify six major states (nodes) on the network leading from the “special pair” to a more symmetric Zundel complex required for transferring the proton. Moreover, the second solvation shell specifically rearranges to promote the transfer, reiterating the idea that solvation beyond the first shell of the Zundel complex plays a crucial role in the process.

  7. Zero emission coal

    SciTech Connect (OSTI)

    Ziock, H.; Lackner, K.

    2000-08-01T23:59:59.000Z

    We discuss a novel, emission-free process for producing hydrogen or electricity from coal. Even though we focus on coal, the basic design is compatible with any carbonaceous fuel. The process uses cyclical carbonation of calcium oxide to promote the production of hydrogen from carbon and water. The carbonation of the calcium oxide removes carbon dioxide from the reaction products and provides the additional energy necessary to complete hydrogen production without additional combustion of carbon. The calcination of the resulting calcium carbonate is accomplished using the high temperature waste heat from solid oxide fuel cells (SOFC), which generate electricity from hydrogen fuel. Converting waste heat back to useful chemical energy allows the process to achieve very high conversion efficiency from fuel energy to electrical energy. As the process is essentially closed-loop, the process is able to achieve zero emissions if the concentrated exhaust stream of CO{sub 2} is sequestered. Carbon dioxide disposal is accomplished by the production of magnesium carbonate from ultramafic rock. The end products of the sequestration process are stable naturally occurring minerals. Sufficient rich ultramafic deposits exist to easily handle all the world's coal.

  8. Infrared Emission from AGN

    E-Print Network [OSTI]

    D. B. Sanders

    1999-03-30T23:59:59.000Z

    Infrared observations of complete samples of active galactic nuclei (AGN) have shown that a substantial fraction of their bolometric luminosity is emitted at wavelengths ~8-1000microns. In radio-loud and Blazar-like objects much of this emission appears to be direct non-thermal synchrotron radiation. However, in the much larger numbers of radio-quiet AGN it is now clear that thermal dust emission is responsible for the bulk of radiation from the near-infrared through submillimeter wavelengths. Luminous infrared-selected AGN are often surrounded by powerful nuclear starbursts, both of which appear to be fueled by enormous supplies of molecular gas and dust funneled into the nuclear region during the strong interaction/merger of gas rich disks. All-sky surveys in the infrared show that luminous infrared AGN are at least as numerous as optically-selected AGN of comparable bolometric luminosity, suggesting that AGN may spend a substantial fraction of their lifetime in a dust-enshrouded phase. The space density of luminous infrared AGN at high redshift may be sufficient to account for much of the X-Ray background, and for a substantial fraction of the far-infrared background as well. These objects plausibly represent a major epoch in the formation of spheroids and massive black holes (MBH).

  9. Elastic emission polishing

    SciTech Connect (OSTI)

    Loewenthal, M.; Loseke, K.; Dow, T.A.; Scattergood, R.O.

    1988-12-01T23:59:59.000Z

    Elastic emission polishing, also called elastic emission machining (EEM), is a process where a stream of abrasive slurry is used to remove material from a substrate and produce damage free surfaces with controlled surface form. It is a noncontacting method utilizing a thick elasto-hydrodynamic film formed between a soft rotating ball and the workpiece to control the flow of the abrasive. An apparatus was built in the Center, which consists of a stationary spindle, a two-axis table for the workpiece, and a pump to circulate the working fluid. The process is controlled by a programmable computer numerical controller (CNC), which presently can operate the spindle speed and movement of the workpiece in one axis only. This apparatus has been used to determine material removal rates on different material samples as a function of time, utilizing zirconium oxide (ZrO{sub 2}) particles suspended in distilled water as the working fluid. By continuing a study of removal rates the process should become predictable, and thus create a new, effective, yet simple tool for ultra-precision mechanical machining of surfaces.

  10. Dijet production in polarized proton-proton collisions at [the square root of sigma] = 200 GeV

    E-Print Network [OSTI]

    Walker, Matthew (Matthew Hsing Hung)

    2011-01-01T23:59:59.000Z

    Polarized deep inelastic scattering (DIS) experiments indicate that quarks only carry approximately 30% of the proton spin, which led to interest in measuring the contributions of other components. Through polarized ...

  11. SU-E-J-122: Detecting Treatment-Induced Metabolic Abnormalities in Craniopharyngioma Patients Undergoing Surgery and Proton Therapy

    SciTech Connect (OSTI)

    Hua, C; Shulkin, B; Li, Y; LI, X; Merchant, T [St. Jude Children's Research Hospital, Memphis, TN (United States); Indelicato, D [University of Florida Proton Therapy Institute, Jacksonville, FL (United States); Boop, F [Semmes-Murphey Neurologic and Spine Institute, Memphis, TN (United States)

    2014-06-01T23:59:59.000Z

    Purpose: To identify treatment-induced defects in the brain of children with craniopharyngioma receiving surgery and proton therapy using fluorodeoxyglucose positron emission tomography (FDG PET). Methods: Forty seven patients were enrolled on a clinical trial for craniopharyngioma with serial imaging and functional evaluations. Proton therapy was delivered using the double-scattered beams with a prescribed dose of 54 Cobalt Gray Equivalent. FDG tracer uptake in each of 63 anatomical regions was computed after warping PET images to a 3D reference template in Talairach coordinates. Regional uptake was deemed significantly low or high if exceeding two standard deviations of normal population from the mean. For establishing the normal ranges, 132 children aged 1–20 years with noncentral nervous system related diseases and normal-appearing cerebral PET scans were analyzed. Age- and gender-dependent regional uptake models were developed by linear regression and confidence intervals were calculated. Results: Most common PET abnormality before proton therapy was significantly low uptake in the frontal lobe, the occipital lobe (particularly in cuneus), the medial and ventral temporal lobe, cingulate gyrus, caudate nuclei, and thalamus. They were related to injury from surgical corridors, tumor mass effect, insertion of a ventricular catheter, and the placement of an Ommaya reservoir. Surprisingly a significantly high uptake was observed in temporal gyri and the parietal lobe. In 13 patients who already completed 18-month PET scans, metabolic abnormalities improved in 11 patients from baseline. One patient had persistent abnormalities. Only one revealed new uptake abnormalities in thalamus, brainstem, cerebellum, and insula. Conclusion: Postoperative FDG PET of craniopharyngioma patients revealed metabolic abnormalities in specific regions of the brain. Proton therapy did not appear to exacerbate these surgery- and tumor-induced defects. In patients with persistent and new abnormalities, continued investigation on clinical symptoms and cognitive outcomes is ongoing to establish the association and predictive values of metabolic imaging.

  12. Proton cloud and the possibility of direct perceiving of a Hydrogen nucleon

    E-Print Network [OSTI]

    Li Yang; Ya-Qi Song

    2014-03-30T23:59:59.000Z

    We introduce a concept of proton cloud and calculate the radius of the proton cloud of the Hydrogen atom. Then, we estimate the radius of the proton cloud of a Hydrogen atom on highly excited Rydberg states. Based on the size of proton cloud, the stability of the atom and technical level, we guess that the direct perceiving of the Hydrogen nucleon cloud, or proton cloud, is possible in near future.

  13. Long-Range Near-Side Angular Correlations in Proton-Proton Interactions in CMS.

    ScienceCinema (OSTI)

    None

    2011-10-06T23:59:59.000Z

    The CMS Collaboration Results on two-particle angular correlations for charged particles emitted in proton-proton collisions at center of mass energies of 0.9, 2.36 and 7TeV over a broad range of pseudorapidity (?) and azimuthal angle (f) are presented using data collected with the CMS detector at the LHC. Short-range correlations in ??, which are studied in minimum bias events, are characterized using a simple independent cluster parameterization in order to quantify their strength (cluster size) and their extent in ? (cluster decay width). Long-range azimuthal correlations are studied more differentially as a function of charged particle multiplicity and particle transverse momentum using a 980nb-1 data set at 7TeV. In high multiplicity events, a pronounced structure emerges in the two-dimensional correlation function for particles in intermediate pT?s of 1-3GeV/c, 2.0< |??|<4.8 and ?f?0. This is the ?rst observation of such a ridge-like feature in two-particle correlation functions in pp or p-pbar collisions. EVO Universe, password "seminar"; Phone Bridge ID: 2330444 Password: 5142

  14. Measurement of the Strange Quark Contribution to Proton Structure through Parity Violating Electron-Proton Scattering

    SciTech Connect (OSTI)

    Kazutaka Nakahara

    2006-05-01T23:59:59.000Z

    The G0 (G-Zero) forward angle experiment completed in Hall C of the Thomas Jefferson National Accelerator Facility (TJNAF) has measured the parity violating asymmetries in elastic electron-proton scattering over a Q2 range of 0.12 < Q2 < 1.0 (GeV/c)2. A linear combination of the strange electric (GsE) and magnetic (GsM) form factors calculated from these asymmetries indicate a non-zero contribution of the strange quark to the charge and magnetization structure of the proton in the above kinematic range at a 89% confidence level. The results show a previously unmeasured Q2 dependence of the strange form factors. Combining the G0 results with previous parity violating experiments show that at Q2 = 0.1 (GeV/c)2 GsM = 0.62+-0.31 GsE = -0.013+-0.028 At intermediate Q2 of about 0.23 (GeV/c)2, a consistent value of GsM is seen compared to previous experiments, together with a measurement that may imply a negative value of GsE. For Q2 above 0.5 (GeV/c)2 a consistently positive value for the linear combination of the strange form factors is seen.

  15. W boson cross sections and single spin asymmetries in polarized proton-proton collisions at [square root of] s =500 GeV at STAR

    E-Print Network [OSTI]

    Corliss, Ross (Ross Cameron)

    2012-01-01T23:59:59.000Z

    Understanding the structure of the proton is an ongoing effort in the particle physics community. Existing in the region of nonperturbative QCD, the various models for proton structure must be informed and constrained by ...

  16. Inclusive jet and dijet production in polarized proton-proton collisions at [the square root of sigma] =200 GeV at RHIC

    E-Print Network [OSTI]

    Sakuma, Tai

    2010-01-01T23:59:59.000Z

    The inclusive jet cross section, the dijet cross section, and the dijet longitudinal double spin asymmetry ALL in polarized proton-proton collisions at [square root of sigma] = 200 GeV are measured with a data sample of ...

  17. Measurements of differential jet cross sections in proton-proton collisions at s?=7??TeV with the CMS detector

    E-Print Network [OSTI]

    Baringer, Philip S.; Bean, Alice; Benelli, Gabriele; Kenny, R. P. III; Murray, Michael J.; Noonan, Danny; Sanders, Stephen J.; Stringer, Robert W.; Tinti, Gemma; Wood, Jeffrey Scott; Chatrchyan, S.; Khachatryan, V.; Sirunyan, A. M.; Tumasyan, A.; Adam, W.; Aguilo, E.; Bergauer, T.; Dragicevic, M.

    2013-06-03T23:59:59.000Z

    Measurements of inclusive jet and dijet production cross sections are presented. Data from LHC proton-proton collisions at s?=7??TeV, corresponding to 5.0??fb(?1) of integrated luminosity, have been collected with the CMS ...

  18. Search for diphoton events with large missing transverse momentum in 7 TeV proton–proton collision data with the ATLAS detector

    E-Print Network [OSTI]

    Taylor, Frank E.

    A search for diphoton events with large missing transverse momentum has been performed using proton–proton collision data at ?s = 7 TeV recorded with the ATLAS detector, corresponding to an integrated luminosity of 4.8 ...

  19. Calculations of Branching Ratios for Radiative-Capture, One-Proton, and Two-Neutron Channels in the Fusion Reaction $^{209}$Bi+$^{70}$Zn

    E-Print Network [OSTI]

    Ichikawa, Takatoshi; 10.1143/JPSJ.79.074201

    2010-01-01T23:59:59.000Z

    We discuss the possibility of the non-one-neutron emission channels in the cold fusion reaction $^{70}$Zn + $^{209}$Bi to produce the element Z=113. For this purpose, we calculate the evaporation-residue cross sections of one-proton, radiative-capture, and two-neutron emissions relative to the one-neutron emission in the reaction $^{70}$Zn + $^{209}$Bi. To estimate the upper bounds of those quantities, we vary model parameters in the calculations, such as the level-density parameter and the height of the fission barrier. We conclude that the highest possibility is for the 2n reaction channel, and its upper bounds are 2.4$%$ and at most less than 7.9% with unrealistic parameter values, under the actual experimental conditions of [J. Phys. Soc. Jpn. {\\bf 73} (2004) 2593].

  20. Calculations of Branching Ratios for Radiative-Capture, One-Proton, and Two-Neutron Channels in the Fusion Reaction $^{209}$Bi+$^{70}$Zn

    E-Print Network [OSTI]

    Takatoshi Ichikawa; Akira Iwamoto

    2010-12-20T23:59:59.000Z

    We discuss the possibility of the non-one-neutron emission channels in the cold fusion reaction $^{70}$Zn + $^{209}$Bi to produce the element Z=113. For this purpose, we calculate the evaporation-residue cross sections of one-proton, radiative-capture, and two-neutron emissions relative to the one-neutron emission in the reaction $^{70}$Zn + $^{209}$Bi. To estimate the upper bounds of those quantities, we vary model parameters in the calculations, such as the level-density parameter and the height of the fission barrier. We conclude that the highest possibility is for the 2n reaction channel, and its upper bounds are 2.4$%$ and at most less than 7.9% with unrealistic parameter values, under the actual experimental conditions of [J. Phys. Soc. Jpn. {\\bf 73} (2004) 2593].

  1. Fuel Mix and Emissions Disclosure

    Broader source: Energy.gov [DOE]

    Electricity suppliers and electricity companies must also provide a fuel mix report to customers twice annually, within the June and December billing cycles. Emissions information must be disclos...

  2. Emission Impacts of Electric Vehicles

    E-Print Network [OSTI]

    Wang, Quanlu; DeLuchi, Mark A.; Sperling, Daniel

    1990-01-01T23:59:59.000Z

    California, 1982. 26. R. E. Simkins, "Evaporative runningevapora- tive emissions. Simkins concluded that runningis consis- tent with Simkins’ result. Weuse EPA’sestimates

  3. Fuel Mix and Emissions Disclosure

    Broader source: Energy.gov [DOE]

    Maryland’s 1999 electric utility restructuring legislation requires all electric companies and electricity suppliers to provide customers with details regarding the fuel mix and emissions of...

  4. Fuel Mix and Emissions Disclosure

    Broader source: Energy.gov [DOE]

    Ohio's 1999 electric industry restructuring law requires the state's electricity suppliers to disclose details regarding their fuel mix and emissions to customers. Electric utilities and...

  5. Fuel Mix and Emissions Disclosure

    Broader source: Energy.gov [DOE]

    Virginia’s 1999 electric industry restructuring law requires the state's electricity providers to disclose -- "to the extent feasible" -- fuel mix and emissions data regarding electric generation....

  6. Emission Impacts of Electric Vehicles

    E-Print Network [OSTI]

    Wang, Quanlu; DeLuchi, Mark A.; Sperling, Daniel

    1990-01-01T23:59:59.000Z

    Simkins, "Evaporative running loss emissions," NIPER- 266,soak emissionsoccur. Running losses are evaporative lossesdiurnal, hot soak, running loss), and gasoline station and

  7. Biodiesel and Pollutant Emissions (Presentation)

    SciTech Connect (OSTI)

    McCormick, R.; Williams, A.; Ireland, J.; Hayes, B.

    2006-09-28T23:59:59.000Z

    Presents the results from three methods of testing--engine, chassis, and PEM--for testing nitrogen oxide (NOx) emissions from B20.

  8. Going Mobile: Emissions Trading Gets a Boost from Mobile Source Emission Reduction Credits

    E-Print Network [OSTI]

    Goldschein, Perry S.

    1995-01-01T23:59:59.000Z

    Going Mobile: Emissions Trading Gets a Boost From Mobilehave tested various emissions trading policies to supplementAn Analysis of EPA's Emissions Trading Program, 6 YALE J. ON

  9. Silicate emission in Orion

    E-Print Network [OSTI]

    D. Cesarsky; A. P. Jones; J. Lequeux; L. Verstraete

    2000-02-14T23:59:59.000Z

    We present mid-infrared spectro-imagery and high-resolution spectroscopy of the Orion bar and of a region in the Orion nebula. These observations have been obtained in the Guaranteed Time with the Circular Variable Filters of the ISO camera (CAM-CVF) and with the Short Wavelength Spectrometer (SWS), on board the European Infrared Space Observatory (ISO). Our data shows emission from amorphous silicate grains from the entire HII region and around the isolated O9.5V star Theta2 Ori A. The observed spectra can be reproduced by a mixture of interstellar silicate and carbon grains heated by the radiation of the hot stars present in the region. Crystalline silicates are also observed in the Orion nebula and suspected around Theta2 Ori A. They are probably of interstellar origin. The ionization structure and the distribution of the carriers of the Aromatic Infrared Bands (AIBs) are briefly discussed on the basis of the ISO observations.

  10. Measurements of the Decays $B^0 \\to \\bar{D}^0\\proton\\antiproton$, $B^0 \\to \\bar{D}^{*0}\\proton\\antiproton$, $B^0 \\to D^{-}\\proton\\antiproton?^+$, and $B^0 \\to D^{*-}\\proton\\antiproton?^+$

    E-Print Network [OSTI]

    The BABAR Collaboration; B. Aubert

    2006-07-21T23:59:59.000Z

    We present measurements of branching fractions of $B^0$ decays to multi-body final states containing protons, based on 232 million $\\Upsilon(4S)\\to B\\bar{B}$ decays collected with the BaBar detector at the SLAC PEP-II asymmetric-energy $B$ factory. We measure the branching fractions ${\\cal B}(B^0 \\to \\bar{D}^0\\proton\\antiproton)=(1.13\\pm0.06\\pm0.08)\\times 10^{-4}$, ${\\cal B}(B^0 \\to \\bar{D}^{*0}\\proton\\antiproton)=(1.01\\pm0.10\\pm0.09)\\times 10^{-4}$, ${\\cal B}(B^0 \\to D^{-}\\proton\\antiproton\\pi^+)=(3.38\\pm0.14\\pm0.29)\\times 10^{-4}$, and ${\\cal B}(B^0 \\to D^{*-}\\proton\\antiproton\\pi^+)=(4.81\\pm0.22\\pm0.44)\\times 10^{-4}$ where the first error is statistical and the second systematic. We present a search for the charmed pentaquark state, $\\Theta_c(3100)$ observed by H1 and put limits on the branching fraction ${\\cal B} (B^0 \\to \\Theta_c \\antiproton\\pi^+)\\times{\\cal B}(\\Theta_c \\to D^{*-}\\proton)proton)<9\\times10^{-6}$. Upon investigation of the decay structure of the above four $B^{0}$ decay modes, we see an enhancement at low $p\\bar{p}$ mass and deviations from phase-space in the $\\bar{D}\\bar{p}$ and $\\bar{D}p$ invariant mass spectra.

  11. X-ray Emission from Massive StarsX-ray Emission from Massive Stars David CohenDavid Cohen

    E-Print Network [OSTI]

    Cohen, David

    X-ray Emission from Massive StarsX-ray Emission from Massive Stars David CohenDavid Cohen/s)Velocity (km/s) #12;absorption emission emission occulted emission emission UV telescope side side front back #12;absorption emission emission occulted emission emission UV telescope side side front back #12;The

  12. Prediction of average. beta. and. gamma. energies and probabilities of. beta. -delayed neutron emission in the region of fission products

    SciTech Connect (OSTI)

    Hirsch, M.; Staudt, A.; Klapdor-Kleingrothaus, H.V. (Max-Planck-Inst. fuer Kernphysik, Heidelberg (Germany))

    1992-07-01T23:59:59.000Z

    Mean {beta} and {gamma} energies and probabilities of {beta}-delayed neutron emission (P{sub n}) in the region of fission products are calculated using a proton-neutron quasiparticle random-phase approximation nuclear model. {beta}-decay properties of these nuclides are essential input parameters for decay heat calculations for nuclear reactors. The results are compared with recent measurements. Mean energies and the P{sub n} values of {approximately}150 experimentally unknown short-lived isotopes are predicted.

  13. Robust optimization of intensity modulated proton therapy

    SciTech Connect (OSTI)

    Liu Wei; Zhang Xiaodong; Li Yupeng; Mohan, Radhe [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States)

    2012-02-15T23:59:59.000Z

    Purpose: Intensity modulated proton therapy (IMPT) is highly sensitive to range uncertainties and uncertainties caused by setup variation. The conventional inverse treatment planning of IMPT optimized based on the planning target volume (PTV) is not often sufficient to ensure robustness of treatment plans. In this paper, a method that takes the uncertainties into account during plan optimization is used to mitigate the influence of uncertainties in IMPT. Methods: The authors use the so-called ''worst-case robust optimization'' to render IMPT plans robust in the face of uncertainties. For each iteration, nine different dose distributions are computed--one each for {+-} setup uncertainties along anteroposterior (A-P), lateral (R-L) and superior-inferior (S-I) directions, for {+-} range uncertainty, and the nominal dose distribution. The worst-case dose distribution is obtained by assigning the lowest dose among the nine doses to each voxel in the clinical target volume (CTV) and the highest dose to each voxel outside the CTV. Conceptually, the use of worst-case dose distribution is similar to the dose distribution achieved based on the use of PTV in traditional planning. The objective function value for a given iteration is computed using this worst-case dose distribution. The objective function used has been extended to further constrain the target dose inhomogeneity. Results: The worst-case robust optimization method is applied to a lung case, a skull base case, and a prostate case. Compared with IMPT plans optimized using conventional methods based on the PTV, our method yields plans that are considerably less sensitive to range and setup uncertainties. An interesting finding of the work presented here is that, in addition to reducing sensitivity to uncertainties, robust optimization also leads to improved optimality of treatment plans compared to the PTV-based optimization. This is reflected in reduction in plan scores and in the lower normal tissue doses for the same coverage of the target volume when subjected to uncertainties. Conclusions: The authors find that the worst-case robust optimization provides robust target coverage without sacrificing, and possibly even improving, the sparing of normal tissues. Our results demonstrate the importance of robust optimization. The authors assert that all IMPT plans should be robustly optimized.

  14. Diffusion-controlled generation of a proton-motive force across a biomembrane

    E-Print Network [OSTI]

    Anatoly Yu. Smirnov; Sergey E. Savel'ev; Franco Nori

    2009-12-04T23:59:59.000Z

    Respiration in bacteria involves a sequence of energetically-coupled electron and proton transfers creating an electrochemical gradient of protons (a proton-motive force) across the inner bacterial membrane. With a simple kinetic model we analyze a redox loop mechanism of proton-motive force generation mediated by a molecular shuttle diffusing inside the membrane. This model, which includes six electron-binding and two proton-binding sites, reflects the main features of nitrate respiration in E. coli bacteria. We describe the time evolution of the proton translocation process. We find that the electron-proton electrostatic coupling on the shuttle plays a significant role in the process of energy conversion between electron and proton components. We determine the conditions where the redox loop mechanism is able to translocate protons against the transmembrane voltage gradient above 200 mV with a thermodynamic efficiency of about 37%, in the physiologically important range of temperatures from 250 to 350 K.

  15. Proton ordering in tetragonal and monoclinic H2O ice

    E-Print Network [OSTI]

    Yen, Fei; Berlie, Adam; Liu, Xiaodi; Goncharov, Alexander F

    2015-01-01T23:59:59.000Z

    H2O ice remains one of the most enigmatic materials as its phase diagram reveals up to sixteen solid phases. While the crystal structure of these phases has been determined, the phase boundaries and mechanisms of formation of the proton-ordered phases remain unclear. From high precision measurements of the complex dielectric constant, we probe directly the degree of ordering of the protons in H2O tetragonal ice III and monoclinic ice V down to 80 K. A broadened first-order phase transition is found to occur near 202 K we attribute to a quenched disorder of the protons which causes a continuous disordering of the protons during cooling and metastable behavior. At 126 K the protons in ice III become fully ordered, and for the case of ice V becoming fully ordered at 113 K forming ice XIII. Two triple points are proposed to exist: one at 0.35 GPa and 126 K where ices III, IX and V coexist; and another at 0.35 GPa and 113 K where ices V, IX and XIII coexist. Our findings unravel the underlying mechanism driving th...

  16. Energy dependence of W values for protons in hydrogen

    E-Print Network [OSTI]

    G. A. Korolev; G. D. Alkhazov; A. V. Dobrovolsky; A. V. Khanzadeev; A. A. Vorobyov

    2014-05-22T23:59:59.000Z

    The mean energy $W$ required to produce an ion pair in molecular hydrogen has been obtained for protons in the energy range between 1 MeV and 4.5 MeV. The W values were derived from the existing experimental data on elastic {\\it $\\pi^-$p} scattering at the beam energy of 40 GeV. In the experiment, the ionization chamber IKAR filled with hydrogen at a pressure of 10 at served simultaneously as a gas target and a detector for recoil protons. For selected events of elastic scattering, the ionization yield produced by recoil protons was measured in IKAR, while the energy was determined kinematically through the scattering angles of the incident particles measured with a system of multi-wire proportional chambers. The ionization produced by $\\alpha$-particles from $\\alpha$-sources of $^{234}$U deposited on the chamber electrodes was used for absolute normalization of the W values. The energy dependence of $W$ for protons in H$_2$ shows an anomalous increase of $W$ with increasing energy in the measured energy range. At the energy of 4.76 MeV, the ionization yield for alpha particles is by 2\\% larger than that for protons.

  17. Proton Pump Inhibitors and Lower Serum Ferritin Levels in 171 HFE C282Y Homozygotes in the Hemochromatosis and Iron Overload Screening Study

    E-Print Network [OSTI]

    2013-01-01T23:59:59.000Z

    antagonist, than by the proton pump inhibitor lansoprazole.Bomford A (2007) Proton pump inhibitors suppress absorptionPatient compliance with proton pump inhibitor therapy in an

  18. Proton Pump Inhibitors and Lower Serum Ferritin Levels in 171 HFE C282Y Homozygotes in the Hemochromatosis and Iron Overload Screening Study

    E-Print Network [OSTI]

    2013-01-01T23:59:59.000Z

    antagonist, than by the proton pump inhibitor lansoprazole.Powell JJ, Bomford A (2007) Proton pump inhibitors suppressand characterization of a mammalian proton-coupled metal-ion

  19. The State of Water in Proton Conducting Membranes

    SciTech Connect (OSTI)

    Allcock, Harry R., Benesi, Alan, Macdonald, Digby, D.

    2010-08-27T23:59:59.000Z

    The research carried out under grant No. DE-FG02-07ER46371, "The State of Water in Proton Conducting Membranes", during the period June 1, 2008 -May 31, 2010 was comprised of three related parts. These are: 1. An examination of the state of water in classical proton conduction membranes with the use of deuterium T1 NMR spectroscopy (Allcock and Benesi groups). 2. A dielectric relaxation examination of the behavior of water in classical ionomer membranes (Macdonald program). 3. Attempts to synthesize new proton-conduction polymers and membranes derived from the polyphosphazene system. (Allcock program) All three are closely related, crucial aspects of the design and development of new and improved polymer electrolyte fuel cell membranes on which the future of fuel cell technology for portable applications depends.

  20. Laser photon merging in proton-laser collisions

    E-Print Network [OSTI]

    A. Di Piazza; K. Z. Hatsagortsyan; C. H. Keitel

    2009-06-30T23:59:59.000Z

    The quantum electrodynamical vacuum polarization effects arising in the collision of a high-energy proton beam and a strong, linearly polarized laser field are investigated. The probability that laser photons merge into one photon by interacting with the proton`s electromagnetic field is calculated taking into account the laser field exactly. Asymptotics of the probability are then derived according to different experimental setups suitable for detecting perturbative and nonperturbative vacuum polarization effects. The experimentally most feasible setup involves the use of a strong optical laser field. It is shown that in this case measurements of the polarization of the outgoing photon and and of its angular distribution provide promising tools to detect these effects for the first time.

  1. Comments on Injector Proton Beam Study in Run 2014

    SciTech Connect (OSTI)

    Zhang, S. Y. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.

    2014-09-15T23:59:59.000Z

    During the entire period of injector proton study in run 2014, it seems that the beam transverse emittance out of Booster is larger than that in run 2013. The emittance measured at the BtA transfer line and also the transmission from Booster late to AGS late are presented for this argument. In addition to this problem, it seems that the multiturn Booster injection, which defines the transverse emittance, needs more attention. Moreover, for high intensity operations, the space charge effect maybe already relevant in RHIC polarized proton runs. With the RHIC proton intensity improvement in the next several years, higher Booster input intensity is needed, therefore, the space charge effect at the Booster injection and early ramp may become a new limiting factor.

  2. Experimental nanocalorimetry of protonated and deprotonated water clusters

    SciTech Connect (OSTI)

    Boulon, Julien; Braud, Isabelle; Zamith, Sébastien; Labastie, Pierre; L’Hermite, Jean-Marc [Université de Toulouse, UPS, Laboratoire Collisions Agrégats Réactivité, IRSAMC, F-31062 Toulouse (France) [Université de Toulouse, UPS, Laboratoire Collisions Agrégats Réactivité, IRSAMC, F-31062 Toulouse (France); CNRS, UMR 5589, F-31062 Toulouse (France)

    2014-04-28T23:59:59.000Z

    An experimental nanocalorimetric study of mass selected protonated (H{sub 2}O){sub n}H{sup +} and deprotonated (H{sub 2}O){sub n?1}OH{sup ?} water clusters is reported in the size range n = 20–118. Water cluster's heat capacities exhibit a change of slope at size dependent temperatures varying from 90 to 140 K, which is ascribed to phase or structural transition. For both anionic and cationic species, these transition temperatures strongly vary at small sizes, with higher amplitude for protonated than for deprotonated clusters, and change more smoothly above roughly n ? 35. There is a correlation between bonding energies and transition temperatures, which is split in two components for protonated clusters while only one component is observed for deprotonated clusters. These features are tentatively interpreted in terms of structural properties of water clusters.

  3. Acceleration of polarized protons in the Brookhaven AGS

    SciTech Connect (OSTI)

    Terwilliger, K.M.; Crabb, D.G.; Krisch, A.D.

    1981-01-01T23:59:59.000Z

    A multi-laboratory-university collaborative project involving Argonne, Brookhaven, Michigan, Rice and Yale is underway to accelerate polarized protons at the AGS. The success of the now turned off 12 GeV/c ZGS polarized beam and the design studies for the AGS made us confident of the feasibility of achieving a polarization of about 60% at 26 GeV/c with an intensity 10/sup 11/ to 10/sup 12/ protons/pulse. Such a beam would be a potential source of polarized protons for ISABELLE. This report gives a brief discussion of the overall project and describes the tests of a prototype of the fast pulsed ferrite quadrupole magnets which will jump the intrinsic depolarizing resonances.

  4. Differential cross section for neutron-proton bremsstrahlung

    E-Print Network [OSTI]

    Y. Safkan; T. Akdogan; W. A. Franklin; J. L. Matthews; W. M. Schmitt; V. V. Zelevinsky; P. A. M. Gram; T. N. Taddeucci; S. A. Wender; S. F. Pate

    2007-03-21T23:59:59.000Z

    The neutron-proton bremsstrahlung process $(np \\to np\\gamma)$ is known to be sensitive to meson exchange currents in the nucleon-nucleon interaction. The triply differential cross section for this reaction has been measured for the first time at the Los Alamos Neutron Science Center, using an intense, pulsed beam of up to 700 MeV neutrons to bombard a liquid hydrogen target. Scattered neutrons were observed at six angles between 12$^\\circ$ and 32$^\\circ$, and the recoil protons were observed in coincidence at 12$^\\circ$, 20$^\\circ$, and 28$^\\circ$ on the opposite side of the beam. Measurement of the neutron and proton energies at known angles allows full kinematic reconstruction of each event. The data are compared with predictions of two theoretical calculations, based on relativistic soft-photon and non-relativistic potential models.

  5. Emission Inventories and Projections

    SciTech Connect (OSTI)

    Streets, D. G.; van Aardenne, John; Battye, Bill; Garivait, Savitri; Grano, D.; Guenther, Alex; Klimont, Z.; Lamarque, Jean-Francois; Lu, Zifeng; Maenhout, Greet; Ohara, Toshimasa; Parrish, David J.; Smith, Steven J.; Vallack, Harry

    2011-04-21T23:59:59.000Z

    When the Executive Body to the Convention on Long-range Transboundary Air Pollution took the decision to establish the Task Force on Hemispheric Transport of Air Pollution (TF HTAP) in December 2004, it was on the basis of a growing understanding of the issues surrounding the hemispheric and intercontinental transport of air pollutants. It was recognised that whilst current regional emissions on their own created pollution levels that exceeded internationally-agreed air quality objectives, hemispheric transport could exacerbate local and regional air quality problems.Two particular pollutants of concern, and the focus of this report, are ozone and particulate matter (PM), known for their detrimental impacts on human health (these impacts and others are described in Chapter 5). There was well-documented evidence for the intercontinental transport of ozone and PM but, at that time, the significance of this intercontinental influence on the design of air pollution control policies was not well understood. The European Union, in drawing up its Thematic Strategy on Clean Air for Europe during 2004, became aware of the significance of intercontinental transport and the importance of sources of pollution beyond its borders and sphere of influence, in meeting its air quality goals.

  6. The Proton Form Factor Ratio Measurements at Jefferson Lab

    SciTech Connect (OSTI)

    Punjabi, Vina A. [Norfolk State University, Norfolk, VA (United States); Perdrisat, Charles F. [William and Mary College, Williamsburg, VA (United States)

    2014-03-01T23:59:59.000Z

    The ratio of the proton form factors, G{sub Ep}/G{sub Mp}, has been measured from Q{sup 2} of 0.5 GeV{sup 2} to 8.5 GeV{sup 2}, at the Jefferson Laboratory, using the polarization transfer method. This ratio is extracted directly from the measured ratio of the transverse and longitudinal polarization components of the recoiling proton in elastic electron-proton scattering. The discovery that the proton form factor ratio measured in these experiments decreases approximately linearly with four-momentum transfer, Q{sup 2}, for values above #25;~1 GeV{sup 2}, is one of the most significant results to come out of JLab. These results have had a large impact on progress in hadronic physics; and have required a significant rethinking of nucleon structure. The increasingly common use of the double-polarization technique to measure the nucleon form factors, in the last 15 years, has resulted in a dramatic improvement of the quality of all four nucleon electromagnetic form factors, G{sub Ep}, G{sub Mp}, G{sub En} and G{sub Mn}. There is an approved experiment at JLab, GEP(V), to continue the ratio measurements to 12 GeV{sup 2}. A dedicated experimental setup, the Super Bigbite Spectrometer (SBS), will be built for this purpose. It will be equipped with a focal plane polarimeter to measure the polarization of the recoil protons. The scattered electrons will be detected in an electromagnetic calorimeter. In this presentation, I will review the status of the proton elastic electromagnetic form factors and discuss a number of theoretical approaches to describe nucleon form factors.

  7. China Energy and Emissions Paths to 2030

    E-Print Network [OSTI]

    Fridley, David

    2012-01-01T23:59:59.000Z

    Potential for Electricity Saving and CO2 Emission ReductionPotential for Electricity Saving and CO2 Emission ReductionPotential for Electricity Saving and CO2 Emission Reduction

  8. The supply chain of CO2 emissions

    E-Print Network [OSTI]

    Davis, S. J; Peters, G. P; Caldeira, K.

    2011-01-01T23:59:59.000Z

    In almost all cases, the emissions related to traded fuelsextraction (F Er ) and production (F Pr ) emissions (i.e. ,the net effect of emissions from traded fossil fuels; Top),

  9. Recent increases in global HFC-23 emissions

    E-Print Network [OSTI]

    2010-01-01T23:59:59.000Z

    of U.S. greenhouse gas emissions and sinks: 1990-2007, Rep.A. Lindley (2007), Global emissions of HFC-23 estimated to2009), Greenhouse Gas Emissions Data, http://unfccc.int/ghg_

  10. Reducing Greenhouse Emissions and Fuel Consumption

    E-Print Network [OSTI]

    Shaheen, Susan; Lipman, Timothy

    2007-01-01T23:59:59.000Z

    that energy use and CO2 emissions in developed countries w icap-and-trade program for CO2 emissions from the electricalout and "sequester" the CO2 emissions, though the cost and

  11. Reducing Greenhouse Emissions and Fuel Consumption

    E-Print Network [OSTI]

    Shaheen, Susan; Lipman, Timothy

    2007-01-01T23:59:59.000Z

    estimated to produce CO2 emission reductions ranging frombetween low CO2 emissions and the reductions in the auto usea 16 percent reduction in CO2 traffic emissions within the

  12. China Energy and Emissions Paths to 2030

    E-Print Network [OSTI]

    Fridley, David

    2012-01-01T23:59:59.000Z

    Electricity Saving and CO2 Emission Reduction in the Cementfor Fuel Saving and CO2 Emission Reduction in the Iron andElectricity Saving and CO2 Emission Reduction in the Iron

  13. Wildland fire emissions, carbon, and climate: U.S. emissions inventories Narasimhan K. Larkin a,

    E-Print Network [OSTI]

    Wildland fire emissions, carbon, and climate: U.S. emissions inventories Narasimhan K. Larkin a: Fire emissions Emissions inventories Greenhouse gases a b s t r a c t Emissions from wildland fire fire emissions change considerably due to fluctuations from year to year with overall fire season

  14. Search for supersymmetry using a photon, b-jets, and ETmiss final state with the ATLAS detector in proton-proton collisions at 8 TeV center-of-mass energy

    E-Print Network [OSTI]

    Kuhl, Andrew

    2015-01-01T23:59:59.000Z

    Abe et al. , “Search for proton decay via p ? ?K + using 260AND E T miss FINAL STATE WITH THE ATLAS DETECTOR IN PROTON-PROTON COLLISIONS AT 8 TEV CENTER-OF-MASS ENERGY A

  15. Exotic modes of excitation in proton rich nuclei

    SciTech Connect (OSTI)

    Paar, N. [Physics Department, Faculty of Science, University of Zagreb (Croatia)

    2011-11-30T23:59:59.000Z

    The framework of relativistic energy density functional has been applied in description of excitation phenomena in nuclei close to the proton drip line. In particular, low-lying dipole excitations have been studied using relativistic quasiparticle random phase approximation, based on effective Lagrangians with density dependent meson nucleon couplings. In the isovector dipole channel, the occurrence of pronounced low-lying dipole peaks is predicted, corresponding to the proton pygmy dipole resonance. Since this exotic mode still awaits its experimental confirmation, systematic calculations have been conducted within a pool of neutron deficient nuclei, in order to identify the best possible candidates for measurements.

  16. Rapid Proton Transfer Mediated by a Strong Laser Field

    SciTech Connect (OSTI)

    Markevitch, Alexei N.; Levis, Robert J. [Department of Chemistry, Center for Advanced Photonics Research, Temple University, Philadelphia, Pennsylvania 19122 (United States); Romanov, Dmitri A. [Department of Physics, Center for Advanced Photonics Research, Temple University, Philadelphia, Pennsylvania 19122 (United States); Smith, Stanley M. [Department of Chemistry, Wayne State University, Detroit, Michigan 48202 (United States)

    2006-04-28T23:59:59.000Z

    Kinetic energy distributions of H{sup +} ejected from a polyatomic molecule, anthraquinone, subjected to 60 fs, 800 nm laser pulses of intensity between 0.2 and 4.0x10{sup 14} W{center_dot}cm{sup -2}, reveal field-driven restructuring of the molecule prior to Coulomb explosion. Calculations demonstrate fast intramolecular proton migration into a field-dressed metastable potential energy minimum. The proton migration occurs in the direction perpendicular to the polarization of the laser field. Rapid field-mediated isomerization is an important new phenomenon in coupling of polyatomic molecules with intense lasers.

  17. Proton polarizabilities from polarized Compton scattering: low-energy expansion

    E-Print Network [OSTI]

    Nadiia Krupina

    2014-05-06T23:59:59.000Z

    We reexamine the low-energy expansion of polarized Compton scattering off the proton and show that the leading non-Born contribution to the beam asymmetry of low-energy Compton scattering is given by the magnetic polarizability alone, the electric polarizability cancels out. Based on this fact we propose to determine the magnetic dipole polarizability of the proton from the beam asymmetry. We also present the low-energy expansion of doubly-polarized observables, from which the spin polarizabilities can be extracted.

  18. Separable Representation of Proton-Nucleus Optical Potentials

    E-Print Network [OSTI]

    L. Hlophe; V. Eremenko; Ch. Elster; F. M. Nunes; G. Arbanas; J. E. Escher; I. J. Thompson

    2014-09-14T23:59:59.000Z

    Recently, a new approach for solving the three-body problem for (d,p) reactions in the Coulomb-distorted basis in momentum space was proposed. Important input quantities for such calculations are the scattering matrix elements for proton- and neutron-nucleus scattering. We present a generalization of the Ernst-Shakin-Thaler scheme in which a momentum space separable representation of proton-nucleus scattering matrix elements can be calculated in the Coulomb basis. The viability of this method is demonstrated by comparing S-matrix elements obtained for p$+^{48}$Ca and p$+^{208}$Pb for a phenomenological optical potential with corresponding coordinate space calculations.

  19. Laser assisted proton collision on light nuclei at moderate energies

    E-Print Network [OSTI]

    I. F Barna; S. Varro

    2014-06-24T23:59:59.000Z

    We present analytic angular differential cross section model for laser assisted proton nucleon scattering on a Woods-Saxon optical potential where the nth-order photon absorption is taken into account simultaneously. As a physical example we calculate cross sections for proton - $^{12}$C collision at 49 MeV in the laboratory frame where the laser intensity is in the range of $ 10^{7} - 10^{21}$ W/cm$^2$ at optical frequencies. The upper intensity limit is slightly below the relativistic regime.

  20. COMPARATIVE STUDIES OF PROTON ACCELERATORS FOR HIGH POWER APPLICATIONS.

    SciTech Connect (OSTI)

    WENG, W.T.

    2006-05-29T23:59:59.000Z

    There are many applications requiring high power proton accelerators of various kinds. However, each type of proton accelerator can only provide beam with certain characteristics, hence the match of accelerators and their applications need careful evaluation. In this talk, the beam parameters and performance limitations of linac, cyclotron, synchrotron, and FFAG accelerators are studied and their relative merits for application in neutron, muon, neutrino, and ADS will be assessed in terms of beam energy, intensity, bunch length, repetition rate, and beam power requirements. A possible match between the applications and the accelerator of choice is presented in a matrix form. The accelerator physics and technology issues and challenges involved will also be discussed.