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in subjects: "Nuclear Data Collections"

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Challenges in the Twentieth Century and Beyond: Computer codes and data

The second half of the twentieth century has seen major changes in computer architecture. In the early fifties to the early seventies, the word ``computes`` demanded reverence, respect and even fear. Computers, then, were almost ``untouchable``. Today, computers have become the mainstreams of communication on the rapidly expanding communication highways. They have become necessities of life. With the computers came the establishment of information centers -- tasked with the dissemination of new… more

Date: December 1, 1995

Creator: Kirk, B.L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Benchmarking of MCNP against B&W LRC Core XI critical experiments

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: Article

Partner: UNT Libraries Government Documents Department

open access

New enhancements to SCALE for criticality safety analysis

As the speed, available memory, and reliability of computer hardware increases and the cost decreases, the complexity and usability of computer software will increase, taking advantage of the new hardware capabilities. Computer programs today must be more flexible and user friendly than those of the past. Within available resources, the SCALE staff at Oak Ridge National Laboratory (ORNL) is committed to upgrading its computer codes to keep pace with the current level of technology. This paper e… more

Date: September 1, 1995

Creator: Hollenbach, D.F.; Bowman, S.M.; Petrie, L.M. & Parks, C.V.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Measurements of delayed neutron emission from Np-237, Am-241, and Am-243

Isotopes of transuranic elements are produced as a result of successive radiative capture reactions in the fuel of a nuclear reactor. Typically, these transuranic isotopes decay through long chains, have long half lives and dominate the long term toxicity of the spent reactor fuel. One of the options for waste management is to remove the transuranic from spent fuel by chemical processing, to load them into new special fuel elements, and to transmute them by neutron induced fission into shorter-… more

Date: December 1995

Creator: Saleh, H. H.; Parish, T. A. & Raman, S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Criticality benchmark results for the ENDF60 library with MCNP{trademark}

The continuous-energy neutron data library ENDF60, for use with the Monte Carlo N-Particle radiation transport code MCNP4A, was released in the fall of 1994. The ENDF60 library is comprised of 124 nuclide data files based on the ENDF/B-VI (B-VI) evaluations through Release 2. Fifty-two percent of these B-VI evaluations are translations from ENDF/B-V (B-V). The remaining forty-eight percent are new evaluations which have sometimes changed significantly. Among these changes are greatly increased … more

Date: July 1, 1995

Creator: Keen, N. D.; Frankle, S. C. & MacFarlane, R. E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Neutron and Non-Neutron Nuclear Data for Radiation Dosimetry

NEUTRON NUCLEAR DATA THAT IS USED IN REACTOR DOSIMETRY INCLUDE THERMAL NEUTRON CROSS SECTIONS AND NEUTRON RESONANCE INTEGRALS, FISSION SPECTRUM AVERAGED CROSS SECTIONS FOR REACTIONS ON A TARGET NUCLEUS. NON-NEUTRON NUCLEAR DATA USED IN REACTOR DOSIMETRY INCLUDE ISOTOPIC COMPOSITIONS OF TARGET NUCLIDES AND RADIOACTIVE HALF-LIVES, GAMMA-RAY ENERGIES AND INTENSITIES OF REACTION PRODUCT NUCLIDES. ALL OF THESE DATA ARE PERIODICALLY EVALUATED AND RECOMMENDED VALUES ARE PROVIDED IN THE HANDBOOK OF CHE… more

Date: September 10, 1999

Creator: Holden, N. E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Impact of the ENDF/B-VI Cross Section on the RPV Fluence Determination

The calculations with the broad-group cross-section library Bugle-96, and atom displacement (dpa) cross sections for iron, both derived from ENDF/B-VI data, result in higher calculated fast neutron fluxes, better agreement of calculations with radiometric dosimeter measurements, and significantly slower dpa rate attenuation through pressure vessel walls relative to the results with their predecessors: the Sailor library and ASTM iron dpa cross sections.

Date: September 12, 1999

Creator: Remec, I.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Recent developments pertinent to processing of ENDF/B-6 type resonance cross section data.

In view of our increasing dependence on computations rather than construction and operation of more costly experimental facilities, the rigor and accuracy achievable by calculational methods certainly deserve more attention. This is particularly so for the Monte Carlo methods which are generally regarded as the ultimate computational standard for the entire nuclear community around the globe. One obvious question that one may raise is whether the numerical algorithms deployed to process cross s… more

Date: July 7, 1998

Creator: Hwang, R. N.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Measurement committee of the US cross section evaluation working group. Annual report, 1995

The Cross Section Evaluation Working Group is a long-standing committee charged with the responsibility for organizing and overseeing the U.S. cross-section evaluation effort. It`s main product is the official U.S. evaluated nuclear data file, ENDF; the current version of this file is Version VI. All evaluations included in ENDF are reviewed and approved by CSEWG and issued by the U.S. Nuclear Data Center, Brookhaven National Laboratory. CSEWG is comprised of volunteers from the U.S. nuclear da… more

Date: August 1, 1995

Creator: Smith, D. L. & McLane, V.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Nuclear data needs for application in nuclear criticality safety programs

In nuclear criticality safety applications, a number of important uncertainties have to be addressed to establish the required criticality safety margin of a nuclear system. One source of these uncertainties is the basic nuclear data used to calculate the effective multiplication factor of the system. Before criticality safety calculations are performed, the bias and uncertainties of the codes and cross sections that are used must be determined. Cross-section data are measured, evaluated, and t… more

Date: September 1, 1995

Creator: Leal, L. C.; Westfall, R. M.; Jordan, W. C. & Wright, R. Q.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Upgrades to the WIMS-ANL code.

The dusty old source code in WIMS-D4M has been completely rewritten to conform more closely with current FORTRAN coding practices. The revised code contains many improvements in appearance, error checking and in control of the output. The output is now tabulated to fit the typical 80 column window or terminal screen. The Segev method for resonance integral interpolation is now an option. Most of the dimension limitations have been removed and replaced with variable dimensions within a compile-t… more

Date: October 14, 1998

Creator: Woodruff, W. L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Creation and testing of an ENDF/B-VI neutron data library (ENDF60) for use with MCNP{trademark}

The continuous-energy neutron data library ENDF60, for use with the Monte Carlo N Particle radiation transport code MCNP4A, was released in the fall of 1994. The ENDF60 library is comprised of 124 nuclide data files based on the ENDF/B-VI evaluations through Release 2. Fifty-two percent of these ENDF/B-VI evaluations are translations from ENDF/B-V. The remaining forty-eight percent are new evaluations which have sometimes changed significantly. The new evaluations include important materials fo… more

Date: September 1995

Creator: Frankle, S. C. & MacFarlane, R. E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

ENDF/B-VI chlorine evaluation is deficient

The criticality safety evaluations for the Fuel Cycle Facility Electrorefiner at Argonne-West were reviewed at Oak Ridge National Laboratory (ORNL) to help provide insight into problems that may be caused by inadequate cross-section data. The adequacy of ENDF/B chlorine was questioned because the evaluation was done in 1967 and is a nonresonance material even though chlorine has resonance structure. There are no validation experiments which are similar to the system being analyzed. The analysis… more

Date: September 1, 1995

Creator: Wright, R. Q. & Jordan, W. C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Evaluation of Hylife-II and Sombrero using 175- and 566- group neutron transport and activation cross sections

Recent modifications to the TART Monte Carlo neutron and photon transport code enable calculation of 566-group neutron spectra. This expanded group structure represents a significant improvement over the 50- and 175-group structures that have been previously available. To support use of this new capability, neutron activation cross section libraries have been created in the 175- and 566-group structures starting from the FENDL/A-2.0 pointwise data. Neutron spectra have been calculated for the f… more

Date: June 18, 1999

Creator: Cullen, D; Latkowski, J & Sanz, J

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Adjustment of the (235)U Fission Spectrum

The latest nuclear data are used to examine the sensitivity of the least squares adjustment of the {sup 235}U fission spectrum to the measured reaction rates, dosimetry cross sections, and prior spectrum covariance matrix. All of these parameters were found to be very important in the spectrum adjustment. The most significant deficiency in the nuclear data is the absence of a good prior covariance matrix. Covariance matrices generated from analytic models of the fission spectra have been used i… more

Date: September 14, 1999

Creator: GRIFFIN,PATRICK J. & WILLIAMS,J.G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Testing of the ENDF/B-VI neutron data library ENDF60 for use with MCNP{trademark}

The continuous-energy neutron data library ENDF60, for use with the Monte Carlo N-Particle radiation transport code MCNP4A, was released in the fall of 1994. It is comprised of 124 nuclide data files based on the ENDF/B-Vi evaluations through Release 2. Forty-eight percent of these materials are new or modified evaluations, while the balance are translations from ENDF/B-V. The new evaluations include most of the important materials for criticality safety calculations, and include significant en… more

Date: July 1, 1995

Creator: Frankle, S. C. & MacFarlane, R. E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Nuclear data requirements for fission reactor neutronics calculations.

The paper discusses current European nuclear data measurement and evaluation requirements for fission reactor technology applications and problems involved in meeting the requirements. Reference is made to the NEA High Priority Nuclear Data Request List and to the production of the new JEFF-3 library of evaluated nuclear data. There are requirements for both differential (or basic) nuclear data measurements and for different types of integral measurement critical facility measurements and isoto… more

Date: June 29, 1998

Creator: Finck, P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Recent development of the CINDER`90 transmutation code and data library for actinide transmutation studies

CINDER`90 is a neutron transmutation code evolved from earlier versions of CINDER and REAC, using the algorithm of CINDER with modifications to accommodate the input of additional constant destruction and production rates associated with reactions outside of the code`s particle or energy domain. In conjunction with other codes simulating the radiation environment, CINDER`90 has been used to describe nuclide inventories in a variety of applications. The library of nuclear data, constantly growin… more

Date: September 1, 1995

Creator: Wilson, W. B.; England, T. R.; George, D. C.; Muir, D. W. & Young, P. G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Compared performances of ENDF/B-VI and JEF-2.2 for MOX core physics.

The US is currently evaluating the use of MOX fuel in commercial LWR's for reducing weapons grade Pu stockpiles. The design and licensing processes will require that the validity of the nuclear data libraries and codes used in the effort be demonstrated. Unfortunately, there are only a very limited number of relatively old and non representative integral experiments' freely available to the US programs. This lack of adequate experimental data can be partially remediated by comparing the results… more

Date: July 8, 1998

Creator: Finck, P. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Neutron scattering from elemental uranium and thorium

Differential neutron-scattering cross sections of elemental uranium and thorium are measured from {approx} 4.5 to 10.0 MeV in steps of {approx} 0.5 MeV. Forty or more differential values are obtained at each incident energy, distributed between {approx} 17{degree} and 160{degree}. Scattered-neutron resolutions are carefully defined to encompass contributions from the first four members of the ground-state rotational band (0{sup 2} g.s., 2{sup +}, 4{sup +} and 6{sup +} states). The experimental … more

Date: January 1, 1995

Creator: Smith, A. B. & Chiba, S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Nuclear Science Division 1994 annual report

This report describes the activities of the Nuclear Science Division for the period of January 1, 1994, to December 31, 1994. This was a time of significant accomplishment for all of the programs in the Division. Assembly of the solar neutrino detector at the Sudbury Neutrino Observatory is well under way. All of the components fabricated by LBL were shipped to Sudbury early in the year and our efforts are now divided between assisting the assembly of the detector and preparing software for dat… more

Date: June 1, 1995

Creator: Myers, W.D.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Forecast of criticality experiments and experimental programs needed to support nuclear operations in the United States of America: 1994--1999

This Forecast is generated by the Chair of the Experiment Needs Identification Workgroup (ENIWG), with input from Department of Energy and the nuclear community. One of the current concerns addressed by ENIWG was the Defense Nuclear Facilities Safety Board`s Recommendation 93-2. This Recommendation delineated the need for a critical experimental capability, which includes (1) a program of general-purpose experiments, (2) improving the information base, and (3) ongoing departmental programs. The… more

Date: March 1, 1994

Creator: Rutherford, D.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Recent validation experience with multigroup cross-section libraries and scale

This paper will discuss the results obtained and lessons learned from an extensive validation of new ENDF/B-V and ENDF/B-VI multigroup cross-section libraries using analyses of critical experiments. The KENO V. a Monte Carlo code in version 4.3 of the SCALE computer code system was used to perform the critical benchmark calculations via the automated SCALE sequence CSAS25. The cross-section data were processed by the SCALE automated problem-dependent resonance-processing procedure included in t… more

Date: December 1, 1995

Creator: Bowman, S.M.; Wright, R.Q.; DeHart, M.D.; Parks, C.V. & Petrie, L.M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Effects of Pb and Bi cross sections on ATW subcriticality predictions.

The accelerator-driven transmutation of waste (ATW) system has been proposed for transmuting the long-lived radioactive nuclei of high-level waste to stable or short-lived species. In recent ATW design concepts, lead-bismuth eutectic (LBE), consisting of 44.5% Pb and 55.5% Bi by weight is used as the spallation target, system coolant, and reflector. Because of the excellent neutron reflection properties of LBE, the subcriticality level of ATW is quite sensitive to the cross sections of lead and… more

Date: June 25, 1999

Creator: Khalil, H. S. & Yang, W. S.

Item Type: Article

Partner: UNT Libraries Government Documents Department