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Scale-4 Analysis of Pressurized Water Reactor Critical Configurations: Volume 3-Surry Unit 1 Cycle 2

Description: The requirements of ANSI/ANS 8.1 specify that calculational methods for away-from-reactor criticality safety analyses be validated against experimental measurements. If credit for the negative reactivity of the depleted (or spent) fuel isotopics is desired, it is necessary to benchmark computational methods against spent fuel critical configurations. This report summarizes a portion of the ongoing effort to benchmark away-from-reactor criticality analysis methods using selected critical configu… more
Date: January 1, 1995
Creator: Bowman, S.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Scale-4 Analysis of Pressurized Water Reactor Critical Configurations: Volume 4-Three Mile Island Unit 1 Cycle 5

Description: The requirements of ANSI/ANS-8.1 specify that calculational methods for away-from-reactor criticality safety analyses be validated against experimental measurements. If credit is to be taken for the reduced reactivity of burned or spent fuel relative to its original ''fresh'' composition, it is necessary to benchmark computational methods used in determining such reactivity worth against spent fuel reactivity measurements. This report summarizes a portion of the ongoing effort to benchmark away… more
Date: January 1, 1995
Creator: DeHart, M.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Validation of the WIMSD4M cross-section generation code with benchmark results

Description: The WIMSD4 code has been adopted for cross-section generation in support of the Reduced Enrichment Research and Test Reactor (RERTR) program at Argonne National Laboratory (ANL). Subsequently, the code has undergone several updates, and significant improvements have been achieved. The capability of generating group-collapsed micro- or macroscopic cross sections from the ENDF/B-V library and the more recent evaluation, ENDF/B-VI, in the ISOTXS format makes the modified version of the WIMSD4 code… more
Date: January 1, 1995
Creator: Deen, J. R.; Woodruff, W. L. & Leal, L. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Search for strangelets and other rare objects in Au + Pt collisions at the AGS using a fixed-angle focusing spectrometer

Description: During the 1993 AGS heavy ion run, experiment E886 conducted a strangelet search in Au + Pt reactions, with beam momentum of 10.8 GeV/c per nucleon. Presented here are the upper limit for strangelet production, invariant cross sections for p, t, d, {sup 3}He, {sup 4}He, {sup 6}He, {sup 8}He, {sup 6}Li, {sup 7}Li, {sup 8}Li and {sup 7}Be, along with a demonstration of their agreement with a coalescence model fit to data collected by E886 during the 1992 engineering run, and upper limits for prod… more
Date: December 31, 1995
Creator: Rusek, A.; Bassalleck, B.; Fischer, H.; Berdoz, A.; Franklin, G. B.; Buerger, T. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The Inclusive Muon Neutrino Reaction In 12C

Description: We calculate the charged current inclusive cross section for the reaction, v(sub)u +12C ->u^- + X, from the threshold to 300 MeV.In addition we obtain the average cross section over the spectrum currently being produced at LAMPF.We discuss our results with respect to the current experimental work and consider the possible contributions from higher l states.
Date: November 1, 1995
Creator: Pourkaviani, M. & Mintz, S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Scale-4 Analysis of Pressurized Water Reactor Critical Configurations: Volume 1-Summary

Description: The requirements of ANSI/ANS 8.1 specify that calculational methods for away-from-reactor criticality safety analyses be validated against experimental measurements. If credit is to be taken for the reduced reactivity of burned or spent fuel relative to its original ''fresh'' composition, it is necessary to benchmark computational methods used in determining such reactivity worth against spent fuel reactivity measurements. This report summarizes a portion of the ongoing effort to benchmark away… more
Date: January 1, 1995
Creator: DeHart, M.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Neutron Dosimetry of the HFIR Hydraulic Facility

Description: The total, fast, and thermal neutron fluxes at five axial positions in the High Flux Isotope Reactor (HFIR) hydraulic tube have been measured using bare and/or cadmium-covered activation, fission, and helium accumulation flux monitors. The spectrum-averaged, one-group cross sections over selected energy ranges for the reactions used in the measurements were obtained using cross sections from the ENDF/B-V file, and the target region volume-integrated spectrum was calculated with DORT, a two-dime… more
Date: January 1, 1995
Creator: Mahmood, S.T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Measurement of inclusive triple differential dijet cross section, d{sup 3}{sigma}/dE{sub T}d{eta}{sub 1}d{eta}{sub 2} in p{bar p} collisions at {radical}s = 1.8 TeV

Description: Measurement of the inclusive triple differential dijet cross section, d{sup 3}{sigma}/dE{sub T}d{sub {eta}1}d{sub {eta}2}, at a center of mass energy {radical}s = 1.8 TeV with the D0 detector during the 1992--1993 run. The sensitivity of this measurement to different parton distribution functions is explored. A comparison of the data to NLO theory using different parton distributions functions indicates the need for a smaller gluon content in the x range accessible at the Tevatron than is predi… more
Date: July 1995
Creator: Abachi, S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Measurements of the neutron polarized structure function at SLAC

Description: Detailed measurements of unpolarized or spin-averaged nucleon structure functions over the past two decades have led to detailed knowledge of the nucleon`s internal momentum distribution. Polarized nucleon structure function measurements, which probe the nucleon`s internal spin distribution, started at SLAC in 1976. E-142 has recently measured the neutron polarized structure function g{sub 1}{sup n}(x) over the range 0.03 {le} {times} {le} 0.6 at an average Q{sup 2} of 2 GeV{sup 2} and found th… more
Date: August 1, 1995
Creator: Young, C. C. & Collaboration, E-142
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Uranium systems to enhance benchmarks for use in the verification of criticality safety computer models. Final report, February 16, 1990--December 31, 1994

Description: Dr. Robert Busch of the Department of Chemical and Nuclear Engineering was the principal investigator on this project with technical direction provided by the staff in the Nuclear Criticality Safety Group at Los Alamos. During the period of the contract, he had a number of graduate and undergraduate students working on subtasks. The objective of this work was to develop information on uranium systems to enhance benchmarks for use in the verification of criticality safety computer models. During… more
Date: February 24, 1995
Creator: Busch, R. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Adequacy of the 123-group cross-section library for criticality analyses of water-moderated uranium systems

Description: In a recent criticality analysis for an array of water-moderated packages containing highly enriched uranium, the 123-group cross-section library in the SCALE system was observed to have a nonconservative discrepancy of approximately 3 to 3.5% when compared with more recently developed libraries. A simple representative system of UO{sub 2}F{sub 2}-H{sub 2}O was used to identify that the problem results from a lack of resonance data for {sup 235}U. Only a single set of self-shielded cross sectio… more
Date: August 1, 1995
Creator: Parks, C. V.; Wright, R. Q. & Jordan, W. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Radioactive nuclide production and isomeric state branching ratios in P + W reactions to 200 mev

Description: Calculations of nuclide yields from spallation reactions usually assume that the products are formed in their ground states. We are performing calculations of product yields from proton reactions on tungsten isotopes that explicitly account for formation of the residual nuclei in excited states. The Hauser-Feshbach statistical/preequilibrium code GNASH, with full accounting for angular momentum conservation and electromagnetic transitions, is utilized in the calculations. We present preliminary… more
Date: July 1, 1995
Creator: Young, P.G. & Chadwick, M.B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Evaluated cross-section libraries and kerma factors for neutrons up to 100 MeV on {sup 12}C

Description: A program is being carried out at Lawrence Livermore National Laboratory to develop high-energy evaluated nuclear data libraries for use in Monte Carlo simulations of cancer radiation therapy. In this report we describe evaluated cross sections and kerma factors for neutrons with incident energies up to 100 MeV on {sup 12}C. The aim of this effort is to incorporate advanced nuclear physics modeling methods, with new experimental measurements, to generate cross section libraries needed for an ac… more
Date: April 11, 1995
Creator: Chadwick, M.B.; Blann, M.; Cox, L.; Young, P.G. & Meigooni, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Further development of the ion cross section for single event upset: model (HICUP)

Description: The HICUP models are shown to be useful tools for both analyzing cross section data and performing upset rate calculations, thereby allowing the cross section concept to be used in both areas. The angular dependent HICUP model is developed from the RPP geometry and the Weibull density function. It is compared with angular cross section data, showing good agreement. The HICUP model is used to derive the correct scaling laws for transforming cross section data taken off-normal to normal incidence… more
Date: July 1, 1995
Creator: Connell, L. W.; Sexton, F. W. & Prinja, A. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Perturbation theory based on the Variational Nodal Transport method in X-Y-Z geometry

Description: A perturbation method based on the Variational Nodal Method (VNM) of solving the neutron transport equation is developed for three-dimensional Cartesian geometry. The method utilizes the solution of the corresponding adjoint transport equation to calculate changes in the critical eigenvalue due to changes in cross sections. Both first order and exact perturbation theory expressions are derived. The adjoint solution algorithm has been formulated and incorporated into the VNM option of the Argonn… more
Date: July 1, 1995
Creator: Laurin-Kovitz, K.F. & Lewis, E.E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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QCD at D0 and CDF

Description: Selected recent Quantum Chromodynamics (QCD) results from the D0 and CDF experiments at the Fermilab Tevatron are presented and discussed. The inclusive jet and inclusive triple differential dijet cross sections are compared to next-to-leading order QCD calculations. The sensitivity of the dijet cross section to parton distribution functions (for hadron momentum fractions {approximately} 0.01 to {approximately} 0.4) will constrain the gluon distribution of the proton. Two analyses of dijet prod… more
Date: May 1, 1995
Creator: Blazey, G.C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Determining subcriticality for EBR-II

Description: The Experimental Breeder Reactor II (EBR-II) shut down on September 30, 1994 and defueling is under way. Longstanding safety rules for changing subassemblies in the EBR-II reactor grid include requirements on neutron count rates. A different safety strategy is needed for the defueling operations because the count rates will become too low as the Sb-Be neutron source decays and fuel removal reduces neutron multiplication. A key component of the new strategy is to establish a deeply subcritical c… more
Date: June 1, 1995
Creator: Schaefer, R.W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Photon-photon colliders

Description: Since the seminal work by Ginsburg, et at., the subject of giving the Next Linear Collider photon-photon capability, as well as electron-positron capability, has drawn much attention. A 1990 article by V.I. Teinov describes the situation at that time. In March 1994, the first workshop on this subject was held. This report briefly reviews the physics that can be achieved through the photon-photon channel and then focuses on the means of achieving such a collider. Also reviewed is the spectrum of… more
Date: April 1, 1995
Creator: Sessler, Andrew M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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TRANSX/DANT benchmark studies using a ENDF/B-V based MATXS library

Description: A series of 20 benchmark critical experiments were studied using the DANT code with cross section libraries prepared by TRANSX from ENDF/B-V based MATXS libraries. The benchmarks were selected to cover both fast and thermal systems utilizing either uranium or plutonium as the primary fissile isotope. An effort was made to cover the range of isotopes prevalent in nuclear systems, though no heterogeneous thermal plutonium cases were included. The results indicate that the code package and library… more
Date: July 1, 1995
Creator: Johns, R.C.; Mosteller, R.D. & Perry, R.T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Diphoton production in p{bar p} collisions at {radical}s = 1.8 TeV

Description: We present measurements of the inclusive {gamma}{gamma} cross section (as a function of invariant mass and photon {epsilon}{sub {tau}}), in p{bar p} collisions at {radical}s = 1.8 TeV, made using the D0 detector at the Fermilab Tevatron collider. The next is leading order (NLO) QCD prediction is found to be in good agreement with the data. The effects of invariant mass and diphoton balance cuts, which test the next-to-leading order contributions to the cross section, are investigated. We also c… more
Date: July 1, 1995
Creator: Abachi, S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Global shielding analysis for the three-element core advanced neutron source reactor under normal operating conditions

Description: Two-dimensional discrete ordinates radiation transport calculations were performed for a model of the three-element core Advanced Neutron Source reactor design under normal operating conditions. The core consists of two concentric upper elements and a lower element radially centered in the annulus between the upper elements. The initial radiation transport calculations were performed with the DORT two-dimensional discrete ordinates radiation transport code using the 39-neutron-group/44-gamma-ra… more
Date: August 1, 1995
Creator: Slater, C. O. & Bucholz, J. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Recent results from the super EBIT

Description: The Super EBIT device at LLNL can produce and trap any highly charged ion at rest in the laboratory, including bare U{sup 92+} ions. Recently, the ionization cross sections for high-Z hydrogenlike ions have been measured for the first time, and measurements of the L-shell ionization cross sections for uranium ions are in progress. The two-electron contributions to the ground state energies of heliumlike ions have been directly measured using a novel technique, and spectra of 2s-2p transitions i… more
Date: September 15, 1995
Creator: Marrs, R.E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A study of the strong coupling constant using W+ jets processes

Description: The ratio of the number of W + 1 jet to W + 0 jet events is measured with the D0 detector using data from, the 1992--93 Tevatron Collider run. For the W {yields} e{nu} channel with a minimum jet E{sub T} cutoff of 25 GeV, the experimental ratio is 0.065 {+-} 0.003(stat) {+-} 0.007(sys). Next-to-Leading order QCD predictions for various parton distributions agree well with each other and are all over one standard deviation below the measurement. Varying the strong coupling constant {alpha}{sub s… more
Date: July 1, 1995
Creator: Abachi, S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Benchmarking of MCNP against B&W LRC Core XI critical experiments

Description: The MCNP Monte Carlo code and its ENDF/B-V continuous-energy cross- section library previously has been benchmarked against a variety of critical experiments, and that benchmarking recently has been extended to include its ENDF/B-VI continuous-energy cross-section library and additional critical experiments. This study further extends the benchmarking of MCNP and its two continuous-energy libraries to 17 large-scale mockup experiments that closely resemble the core of a pressurized water reacto… more
Date: July 1, 1995
Creator: Mosteller, R.D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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