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Over-the-road tests of nuclear materials package response to normal environments

Description: In support of the development of American National Standards Institute standards for the transport of radioactive materials, Sandia has a program to characterize the normal transport environment. This program includes both analytical modeling of package and trailer responses, and over-the-road tests to measure those responses. This paper presents the results of a series of over-the-road tests performed using Chem-Nuclear equipment in the Barnwell, SC, area. The test events included a variety of… more
Date: December 1, 1991
Creator: Gwinn, K.W.; Glass, R.E. & Edwards, K.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Fast Particle Destabilization of Toroidicity Induced Alfven Eigenmodes in National Spherical Torus Experiment

Description: Toroidicity induced Alfven Eigenmode (TAE) stability in National Spherical Torus Experiment (NSTX) is analyzed using the improved NOVA-K code, which includes finite orbit width and Larmor radius effects and is able to predicts the saturation amplitude for the mode using the quasilinear theory. Broad spectrum of unstable global TAEs with different toroidal mode numbers is predicted. Due to the strong poloidal field and the presence of the magnetic well in NSTX better particle confinement in the … more
Date: December 10, 1999
Creator: Cheng, C. Z.; Fu, G. Y.; Gorelenkova, M. V.; Gorelenkov, N. N.; White, R. & Kaye, S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The high energy behavior of the forward scattering parameters - an amplitude analysis update

Description: Utilizing the most recent experimental data, we reanalyze high energy pp and pp data, using the asymptotic amplitude analysis, under the assumption that we have reached {open_quotes}asymptopia{close_quotes}. This analysis gives strong evidence for a log (s/s{sub 0}) dependence at current energies and not log{sup 2} (s/s{sub 0}), and also demonstrates that odderons are not necessary to explain the experimental data.
Date: December 1995
Creator: Block, M. M.; Margolis, B. & White, A. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Experiment to measure total cross sections, differential cross sections and polarization effects in pp elastic scattering at RHIC

Description: The author is describing an experiment to study proton-proton (pp) elastic scattering experiment at the Relativistic Heavy Ion Collider (RHIC). Using both polarized and unpolarized beams, the experiment will study pp elastic scattering from {radical}s = 60 GeV to {radical}s = 500 GeV in two kinematical regions .In the Coulomb Nuclear Interference (CNI) region, 0.0005 < {vert_bar}t{vert_bar} < 0.12 (GeV/c){sup 2}, we will measure and study the s dependence of the total and elastic cross sections… more
Date: December 31, 1995
Creator: Guryn, W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Theoretical aspects of light meson spectroscopy

Description: In this pedagogical review the authors discuss the theoretical understanding of light hadron spectroscopy in terms of QCD and the quark model. They begin with a summary of the known and surmised properties of QCD and confinement. Following this they review the nonrelativistic quark potential model for q{anti q} mesons and discuss the quarkonium spectrum and methods for identifying q{anti q} states. Finally, they review theoretical expectations for non-q{anti q} states (glueballs, hybrids and mu… more
Date: December 31, 1995
Creator: Barnes, T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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KN scattering in the nonrelativistic quark model

Description: KN scattering is of interest as a probe of nuclear structure and, more fundamentally, as a laboratory for the study of nonresonant hadron-hadron interactions. KN is a I theoretically attractive channel because of its simplicity, having only S = 1/2, no one pion exchange contributions and no valence q{anti q} annihilation. It may therefore be useful for the study of short-ranged quark forces analogous to the NN repulsive core. Since there are two isospin states, comparison of two closely related… more
Date: December 31, 1995
Creator: Barnes, F. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Phase synchronization of multiple klystrons in RF system

Description: The Low Energy Demonstration Accelerator (LEDA) being constructed at Los Alamos National Laboratory will serve as the prototype for the low energy section of the Acceleration Production of Tritium (APT) accelerator. The first LEDA RF system includes three, 1.2 MW, 350 MHz, continuous wave, klystrons driving a radio frequency quadrupole (RFQ). A phase control loop is necessary for each individual klystron in order to guarantee the phase matching of these klystrons. To meet this objective, they p… more
Date: December 31, 1998
Creator: Kwon, S.; Regan, A.; Wang, Y. M. & Rohlev, T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Infrasound from the El Paso super-bolide of October 9, 1997

Description: During the noon hour on October 9, 1997 an extremely bright fireball ({approx}-21.5 in stellar magnitude putting it into the class of a super-bolide) was observed over western Texas with visual sightings from as far away as Arizona to northern Mexico and even in northern New Mexico over 300 miles away. This event produced tremendously loud sonic boom reports in the El Paso area. It was also detected locally by 4 seismometers which are part of a network of 5 seismic stations operated by the Univ… more
Date: December 31, 1998
Creator: ReVelle, D. O.; Whitaker, R. W. & Armstrong, W. T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Vibration modal analysis using all-optical photorefractive processing

Description: A new experimental method for vibration modal analysis based on all- optical photorefractive processing is presented. The method utilizes an optical lock-in approach to measure phase variations in light scattered from optically rough, continuously vibrating surfaces. In this four-wave mixing technique, all-optical processing refers to mixing the object beam containing the frequency modulation due to vibration with a single frequency modulated pump beam in the photorefractive medium that process… more
Date: December 31, 1996
Creator: Hale, T. & Telschow, K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Nucleon-nucleon interactions

Description: Nucleon-nucleon interactions are at the heart of nuclear physics, bridging the gap between QCD and the effective interactions appropriate for the shell model. We discuss the current status of {ital NN} data sets, partial-wave analyses, and some of the issues that go into the construction of potential models. Our remarks are illustrated by reference to the Argonne {ital v}{sub 18} potential, one of a number of new potentials that fit elastic nucleon-nucleon data up to 350 MeV with a {Chi}{sup 2}… more
Date: December 31, 1996
Creator: Wiringa, R.B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Prospects of a baryon instability search in neutron-antineutron oscillations

Description: The purpose of this article is to review the current status and the future prospects for an experimental neutron-antineutron transition search. Traditional and new experimental techniques are discussed here. In the n {r_arrow} {anti n} search in experiments at existing reactors, it would be possible to increase the discovery potential up to four orders of magnitude for vacuum n {r_arrow} {anti n} transitions relative to the existing experimental level or to achieve the limit of {tau}{sub n-{ant… more
Date: December 31, 1996
Creator: Efremenko, Yu. & Kamyshkov, Yu.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Amplitude path corrections for regional phases in China

Description: The authors investigate the effectiveness of amplitude path corrections for regional phases on seismic event discrimination and magnitude estimation. Waveform data from digital stations in China for regional, shallow (< 50 km) events were obtained from the IRIS Data Management Center (DMC) for years 1986 to 1996 using the USGS Preliminary Determination of Epicenters (PDE) and the Chinese State Seismological Bureau (SSB) catalogs. For each event, the amplitudes for each regional phase (P{sub n},… more
Date: December 31, 1998
Creator: Phillips, W. S.; Velasco, A. A.; Taylor, S. R. & Randall, G. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Infrasonic observation of earthquakes

Description: Infrasound signals generated by earthquakes have been detected at arrays operated by the Los Alamos National Laboratory. Three modes of propagation are possible and all have been observed by the authors. The observations suggest that regions remote from the epicenters are excited and may serve as secondary source regions. A relation is found between the normalized peak amplitudes and the seismic magnitudes.
Date: December 31, 1998
Creator: Mutschlecner, J.P. & Whitaker, R.W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Reaction theories for N* excitations in {pi}N and {gamma}N reactions

Description: The importance of developing reaction theories for investigating N* physics is illustrated in an analysis of pion photoproduction on the nucleon. It is shown that the {gamma}N {leftrightarrow} {Delta} transition amplitudes predicted by the constituent quark model are in agreement with the values extracted from the {gamma}N {r_arrow} {pi}N data only when the contributions from the reaction mechanisms calculated using a dynamical approach are taken into account in the analysis.
Date: December 31, 1996
Creator: Lee, T. S. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Amplitude and phase modulation with waveguide optics

Description: We have developed amplitude and phase modulation systems for glass lasers using integrated electro-optic modulators and solid state high- speed electronics. The present and future generation of lasers for Inertial Confinement Fusion require laser beams with complex temporal and phase shaping to compensate for laser gain saturation, mitigate parametric processes such as transverse stimulated Brillouin scattering in optics, and to provide specialized drive to the fusion targets. These functions c… more
Date: December 17, 1996
Creator: Burkhart, S. C.; Wilcox, R. B.; Browning, D. & Penko, F. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Nonlinear Pulsation Modeling of Luminous Blue Variables

Description: Using an updated version of the Ostlie and Cox (1993) nonlinear hydrodynamics code, we show the results of Luminous Blue Variable (LBV) envelope models based on evolution models of initial mass 50-80 M solar. including mass loss. The models use OPAL opacities, contain 60-120 Lagrangian zones, include time dependent convection, and are given an initial photospheric radial velocity amplitude of 1 km/sec. Our goal is to explain the reason for the LBV instability strip and suggest a cause for LBV o… more
Date: December 31, 1997
Creator: Despain, Kate M.; Guzik, Joyce A. & Cox, Arthur N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The Feynman-Schwinger (World Line) Representation in Perturbative QCD

Description: The proper time path integral representation is derived explicitly for an arbitrary $n$-point amplitude in QCD. In the standard perturbation theory the formalism allows to sum up the leading subseries, e.g. yielding double-logarithm Sudakov asymptotics for form factors. Correspondence with the standard perturbation theory is established and connection to the Bern-Kosower-Strassler method is illustrated.
Date: December 1, 2001
Creator: Simonov, Yu A. & Tjon, J.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Upper limits on the strength of periodic gravitational waves from PSR J1939+2134

Description: The first science run of the LIGO and GEO gravitational wave detectors presented the opportunity to test methods of searching for gravitational waves from known pulsars. Here we present new direct upper limits on the strength of waves from the pulsar PSR J1939+2134 using two independent analysis methods, one in the frequency domain using frequentist statistics and one in the time domain using Bayesian inference. Both methods show that the strain amplitude at Earth from this pulsar is less than … more
Date: December 11, 2003
Creator: al., B. Allen et
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Measurement of Beam-Spin Asymmetries for Deep Inelastic pi{sup +} Electroproduction

Description: We report the first evidence for a non-zero beam-spin azimuthal asymmetry in the electroproduction of positive pions in the deep-inelastic region. Data have been obtained using a polarized electron beam of 4.3 GeV and with the CLAS detector at the Thomas Jefferson National Accelerator Facility (JLab). The amplitude of the sin phi modulation increases with the momentum of the pion relative to the virtual photon, z, with an average amplitude of 0.038+/-0.005+/-0.003 for 0.5&lt;z&lt;0.8 range.
Date: December 1, 2002
Creator: Avakian, H.; Burkert, Volker D.; Elouadrhiri, Latifa & al., et.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Synchrotron radiation from electron beams in plasma focusing channels

Description: Spontaneous radiation emitted from relativistic electrons undergoing betatron motion in a plasma focusing channel is analyzed and application to plasma wakefield accelerator experiments and to the ion channel laser (ICL) are discussed. Important similarities and differences between a free electron laser (FEL) and an ICL are delineated. It is shown that the frequency of spontaneous radiation is a strong function of the betatron strength parameter alpha-beta, which plays a similar role to that of… more
Date: December 6, 2001
Creator: Esarey, E.; Shadwick, B. A.; Catravas, P. & Leemans, W. P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Observation of Secondary Plasma Waves in Laser-Plasma Interaction Experiments

Description: An experiment is described where the two products of the Langmuir Decay Instability (LDI) of a primary electron plasma wave have been observed and identified without any ambiguity. Primary Langmuir waves are driven by Stimulated Raman Scattering (SRS) of an incident laser which provides well-defined electron plasma waves. Thomson scattering of a short wavelength probe beam yields measurements of the amplitude of the waves resolved in time, space, wavelength and wavevector, that allow identifica… more
Date: December 8, 1999
Creator: Depierreux, S.; Labaune, C.; Baldis, H. A.; Fuchs, J. & Michard, A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The photon polarization in b -&gt; X gamma in the standard model

Description: The standard model prediction for the {bar B}{sup 0} {yields} X{sub s,d}{gamma} decay amplitude with a right-handed photon is believed to be tiny, suppressed by m{sub s,d}/m{sub b}, compared to the amplitude with a left-handed photon. We show that this suppression is fictitious: in inclusive decays, the ratio of these two amplitudes is only suppressed by g{sub s}/(4{pi}), and in exclusive decays by {Lambda}{sub QCD}/m{sub b}. The suppression is not stronger in {bar B}{sup 0} {yields} X{sub d}{g… more
Date: December 8, 2004
Creator: Grinstein, Benjamin; Grossman, Yuval; Ligeti, Zoltan & Pirjol, Dan
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Quantum non-locality in a two-slit interferometer for short-lived particles

Description: We describe a new test of quantum nonlocality, using an interferometer for short-lived particles. The separation is large compared with the particle lifetimes. This interferometer is realized by vector meson production in distant heavy ion collisions. The mesons decay before waves from the two sources (ions) can overlap, so interference is only possible among the decay products. The post-decay wave function must retain amplitudes for all possible decays. The decay products are spatially separat… more
Date: December 1, 2001
Creator: Klein, Spencer R. & Nystrand, Joakim
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Resonance Contributions to {eta} Photoproduction on Protons Found Using Dispersion Relations and an Isobar Model

Description: The contributions of the resonances D{sub 13}(1520), S{sub 11}(1535), S{sub 11}(1650), D{sub 15}(1675), F{sub 15}(1680), D{sub 13}(1700), P{sub 11}(1710), P{sub 13}(1720) to {gamma}p {yields} {eta}p are found from the data on cross sections, beam and target asymmetries using two approaches: fixed-t dispersion relations and an isobar model. Utilization of the two approaches and comparison of the results obtained with different parametrizations of the resonance contributions allowed us to make co… more
Date: December 1, 2003
Creator: Aznauryan, Inna
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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