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in subjects: "Nuclear Physics"  
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Systematics of neutron-induced fission cross sections over the energy range 0. 1 through 15 MeV, and at 0. 0253 eV

Description: Recent studies have shown straightforward systematic behavior as a function of constant proton and neutron number for neutron-induced fission cross sections of the actinide elements in the incident-neutron energy range 3 to 5 MeV. In this report, the second in a series, fission cross-section values are studied over the MeV incident-neutron energy range, and at 0.0253 eV. Fission-barrier heights and neutron-binding energies are correlated by constant proton and neutron number; however, these sys… more
Date: November 11, 1977
Creator: Behrens, J.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Microscopic Calculations of 240Pu Fission

Description: Hartree-Fock-Bogoliubov calculations have been performed with the Gogny finite-range effective interaction for {sup 240}Pu out to scission, using a new code developed at LLNL. A first set of calculations was performed with constrained quadrupole moment along the path of most probable fission, assuming axial symmetry but allowing for the spontaneous breaking of reflection symmetry of the nucleus. At a quadrupole moment of 345 b, the nucleus was found to spontaneously scission into two fragments.… more
Date: September 11, 2007
Creator: Younes, W & Gogny, D
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Isotopes of Americium

Description: Three new americium activities (Am{sup 238}?, Am{sup 243}, and Am{sup 244?}, the latter two formed by n,{gamma} reactions) are described and some additional information is given on previously reported americium isotopes.
Date: April 11, 1950
Creator: Street, K.; Ghiroso, A. & Seaborg, G. T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Relativistic nuclear many-body theory

Description: Nonrelativistic models of nuclear systems have provided important insight into nuclear physics. In future experiments, nuclear systems will be examined under extreme conditions of density and temperature, and their response will be probed at momentum and energy transfers larger than the nucleon mass. It is therefore essential to develop reliable models that go beyond the traditional nonrelativistic many-body framework. General properties of physics, such as quantum mechanics, Lorentz covariance… more
Date: September 11, 1991
Creator: Serot, B.D. (Indiana Univ., Bloomington, IN (United States)) & Walecka, J.D. (Southeastern Universities Research Association, Newport News, VA (United States). Continuous Electron Beam Accelerator Facility)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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HIJET with AGS physics and N[sup *]'s

Description: We investigate the effects of secondary interactions in nucleus- nucleus and proton-nucleus collisions using a modified HIJET Monte Carlo generator. The effects of N[sup *] production is explored and it is found that the numbers of kaons can almost be explained by their inclusion. However the transverse momentum spectrum of the kaons is not explained, since their production in HIJET is a soft secondary scattering process and not a hot thermal process like the data.
Date: February 11, 1993
Creator: Longacre, R. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Neutral strange particle production at the AGS

Description: We present the results of [Lambda] and K[sub s[sup o]] production from Si and Pb targets with 14.6[times][Lambda] Gev/c Si beams. The measured rapidity distributions and the transverse mass exponential slopes are presented and compared with models.
Date: February 11, 1993
Creator: Saulys, A.C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Activity of fission products

Description: This report compares the activity and disintegration energy of fission products from metal under two conditions of exposure: 200 Megawatt-days integrated exposure over a period of 180 days, and 400 Megawatt-days integrated exposure over a period of 360 days. (JL)
Date: November 11, 1948
Creator: Garbrecht, M. & Gillette, P. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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2D deterministic radiation transport with the discontinuous finite element method

Description: This report provides a complete description of the analytic and discretized equations for 2D deterministic radiation transport. This computational model has been checked against a wide variety of analytic test problems and found to give excellent results. We make extensive use of the discontinuous finite element method.
Date: November 11, 1993
Creator: Kershaw, D. & Harte, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Neutral strange particle production at the AGS

Description: We present the results of {Lambda} and K{sub s{sup o}} production from Si and Pb targets with 14.6{times}{Lambda} Gev/c Si beams. The measured rapidity distributions and the transverse mass exponential slopes are presented and compared with models.
Date: February 11, 1993
Creator: Saulys, A. C. & Collaboration, For the E810
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

HIJET with AGS physics and N{sup *}`s

Description: We investigate the effects of secondary interactions in nucleus- nucleus and proton-nucleus collisions using a modified HIJET Monte Carlo generator. The effects of N{sup *} production is explored and it is found that the numbers of kaons can almost be explained by their inclusion. However the transverse momentum spectrum of the kaons is not explained, since their production in HIJET is a soft secondary scattering process and not a hot thermal process like the data.
Date: February 11, 1993
Creator: Longacre, R. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

High pT hadron spectra at RHIC: an overview

Description: Recent results on high transverse momentum (p{sub T}) hadron production in p+p, d+Au and Au+Au collisions at the Relativistic Heavy Ion Collider (RHIC) are reviewed. Comparison of the nuclear modification factors, R{sub dAu}(p{sub T}) and R{sub AA}(p{sub T}), demonstrates that the large suppression in central Au+Au collisions is due to strong final-state effects. Theoretical models which incorporate jet quenching via gluon Bremsstrahlung in the dense partonic medium that is expected in central … more
Date: October 11, 2004
Creator: Klay, J L
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Discovering New Light States at Neutrino Experiments

Description: Experiments designed to measure neutrino oscillations also provide major opportunities for discovering very weakly coupled states. In order to produce neutrinos, experiments such as LSND collide thousands of Coulombs of protons into fixed targets, while MINOS and MiniBooNE also focus and then dump beams of muons. The neutrino detectors beyond these beam dumps are therefore an excellent arena in which to look for long-lived pseudoscalars or for vector bosons that kinetically mix with the photon.… more
Date: August 11, 2011
Creator: Essig, Rouven; Harnik, Roni; Kaplan, Jared & Toro, Natalia
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Summary of “Future of DIS” Working Group Session

Description: Despite the closure of the HERA accelerator in the past few years, much physics still remains to be understood, from the quark and gluon content of the nucleon/nucleus across all x to the still unknown spin structure of the proton. The 'Future of DIS' working group was dedicated to discussions on these and many other subjects. This paper represents a brief overview of the discussions. For further details, please refer to individual contributions.
Date: April 11, 2011
Creator: M., Lamont; Guzey, V. & Polini, A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Indirect Dark Matter Detection Limits from the Ultra-Faint Milky Way Satellite Segue 1

Description: We use new kinematic data from the ultra-faint Milky Way satellite Segue 1 to model its dark matter distribution and derive upper limits on the dark matter annihilation cross-section. Using gamma-ray ux upper limits from the Fermi satellite and MAGIC, we determine cross-section exclusion regions for dark matter annihilation into a variety of different particles including charged leptons. We show that these exclusion regions are beginning to probe the regions of interest for a dark matter interp… more
Date: August 11, 2011
Creator: Essig, Rouven; Sehgal, Neelima; Strigari, Louis E.; Geha, Marla & Simon, Joshua D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Status report to ERDA Nuclear Data Committee

Description: This status report to the Nuclear Data Committee from LLL summarizes work in the areas of standards, nuclear data applications, nuclear data for safeguards, and nuclear data compilation. A few of these papers, though brief, do contain data. 9 figures, 2 tables. (RWR)
Date: February 11, 1977
Creator: Anderson, J. D.; Browne, J. C. & Gardner, D. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Cosmic Ray Anomalies from the MSSM?

Description: The recent positron excess in cosmic rays (CR) observed by the PAMELA satellite may be a signal for dark matter (DM) annihilation. When these measurements are combined with those from FERMI on the total (e{sup +} + e{sup -}) ux and from PAMELA itself on the {anti p}p ratio, these and other results are difficult to reconcile with traditional models of DM, including the conventional minimal Supergravity (mSUGRA) version of Supersymmetry even if boosts as large as 10{sup 3-4} are allowed. In this … more
Date: August 11, 2011
Creator: Cotta, R. C.; Conley, J. A.; Gainer, J. S.; Hewett, J. L. & Rizzo, T. G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The Radiochemical Analysis of Gaseous Samples (RAGS) Apparatus for Nuclear Diagnostics at the National Ignition Facility

Description: The RAGS (Radiochemical Analysis of Gaseous Samples) diagnostic apparatus was recently installed at the National Ignition Facility. Following a NIF shot, RAGS is used to pump the gas load from the NIF chamber for purification and isolation of the noble gases. After collection, the activated gaseous species are counted via gamma spectroscopy for measurement of the capsule areal density and fuel-ablator mix. Collection efficiency was determined by injecting a known amount of {sup 135}Xe into the … more
Date: May 11, 2012
Creator: Shaughnessy, D A; Velsko, C A; Jedlovec, D R; Yeamans, C B; Moody, K J; Tereshatov, E et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Indirect Determination of the 230Th(n,f) and 231Th(n,f) Cross Sections for Thorium-Based Nuclear Energy Systems

Description: The Surrogate Ratio Method (SRM) was employed in the first experimental determination of the 231Th(n,f) cross section, relative to the 235U(n,f) cross section, over an equivalent neutron energy range of 360 keV to 10 MeV. The 230Th(n,f) cross section was also deduced using the SRM, relative to the 234U(n,f) cross section, over an equivalent neutron energy range of 220 keV to 25 MeV. The desired compound nuclei were populated using (3He,3He) and (3He) reactions on targets of 232Th and 236U and r… more
Date: September 11, 2009
Creator: Stroberg, S.R.; Allmond, J.M.; Angell, C.; Bernstein, L.A.; Bleuel, D.L.; Burke, J.T. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Reevaluation of the gamma-ray energies and absolute branching intensities of /sup 237/U, /sup 238/ /sup 239/ /sup 240/ /sup 241/Pu, and /sup 241/Am

Description: Promising new techniques for making quantitative measurements of plutonium require highly precise values of the gamma-ray energies and intensities for the isotopes involved. Using high isotopic purity sources and state of the art Ge(Li) detectors, we have reevaluated the energies and absolute emission probabilities of the gamma rays following the decay of /sup 237/U, /sup 238/, /sup 239/, /sup 240/, /sup 241/Pu, and /sup 241/Am.
Date: October 11, 1976
Creator: Gunnink, R.; Evans, J. E. & Prindle, A. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Studies of the Electromagnetic Structure of Mesons at Jefferson Lab

Description: The Jefferson Laboratory Hall B PrimEx Collaboration is using tagged photons to perform an absolute 1.4% level cross section measurement of the photoproduction of neutral pions in the Coulomb field of a nucleus. The absolute cross section for this process is directly proportional to the neutral pion radiative decay width and consequently the uncertainty in the luminosity is directly reflected in the final error bar of the measurement. The PI has taken primary responsibility for the photon flux … more
Date: November 11, 2012
Creator: Dale, Daniel, S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Low cost digital electronics for isotope analysis with microcalorimeters - final report

Description: The overall goal of the Phase I research was to demonstrate that the digital readout electronics and filter algorithms developed by XIA for use with HPGe detectors can be adapted to high precision, cryogenic gamma detectors (microcalorimeters) and not only match the current state of the art in terms of energy resolution, but do so at a significantly reduced cost. This would make it economically feasible to instrument large arrays of microcalorimeters and would also allow automation of the setup… more
Date: September 11, 2006
Creator: Hennig, W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Dark Matter Burners: Preliminary Estimate

Description: We show that a star orbiting close enough to an adiabatically grown supermassive black hole can capture a large number of weakly interacting massive particles (WIMPs) during its lifetime. WIMP annihilation energy release in low- to medium-mass stars is comparable with or even exceeds the luminosity of such stars due to thermonuclear burning. The excessive energy release in the stellar core may result in an evolution scenario different from what is expected for a regular star. The model thus pre… more
Date: September 11, 2006
Creator: Moskalenko, Igor V.; /Stanford U., HEPL & Wai, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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