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in creator/contributor: "Larson, D.C."

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Evaluation of cross sections for neutron-induced reactions in sodium. [10/sup -5/ eV to 20 MeV]

An evaluation of the neutron-induced cross sections of /sup 23/Na has been done for the energy range from 10/sup -5/ eV to 20 MeV. All significant cross sections are given, including differential cross sections for production of gamma rays. The recommended values are based on experimental data where available, and use results of a consistent model code analysis of available data to predict cross sections where there are no experimental data. This report describes the evaluation that was submitt… more

Date: September 1, 1980

Creator: Larson, D.C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

ORELA measurements to meet fusion energy neutron cross section needs. [2 to 80 MeV]

Major neutron cross section measurements made at the Oak Ridge Electron Linear Accelerator (ORELA) that are useful to the fusion energy program are reviewed. Cross sections for production of gamma rays with energies 0.3 < E/sub ..gamma../ < 10.5 MeV were measured as a function of neutron energy over the range 0.1 < E/sub n/ < 20.0 MeV for Li, C, N, O, F, Na, Mg, Al, Si, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Nb, Mo, Ag, Sn, Ta, W, Au, Pb, and Th. Neutron emission cross sections have been measured f… more

Date: January 1, 1980

Creator: Larson, D.C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Gamma-ray decay of levels in /sup 53/Cr

Gamma-ray decay of levels in the stable isotope /sup 53/Cr has been studied using /sup 53/Cr(n,n'..gamma..) reactions for incident neutron energies between threshold and 10 MeV. Of the 65 gamma rays or gamma-ray groups observed for neutron interactions with /sup 53/Cr, 50 have been placed or tentatively placed among 34 levels in /sup 53/Cr up to an excitation energy of 4.36 MeV. Deduced branching ratios are in reasonable agreement with previous measurements except for decay of the E/sub x/ = 15… more

Date: November 1, 1987

Creator: Dickens, J.K. & Larson, D.C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Potential improvements to ENDF/B-VI for fusion data

While ENDF/B-6 is significant improvement over previous versions for fusion reactor design calculations, several areas have not received attention and may need improvement. In addition, broadening of the contents of the evaluations to contain information not easily derived at present should be considered. 11 refs.

Date: January 1, 1991

Creator: Larson, D.C. & Fu, C.Y.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

High-resolution structural material (n,x. gamma. ) production cross sections for 0. 2 < E/sub n/ less than or equal to 40 MeV

An experimental program has been initiated at the Oak Ridge electron Linear Accelerator (ORELA) to measure yields of individual gamma rays resulting from interactions of 0.2- to 40-MeV neutrons with elements of structural materials of interest both for applied needs and basic research. In this paper we outline this program and present some cross-section results for /sup nat/Cr(n,x..gamma..) , /sup 56/Fe(n,x..gamma..) and /sup 58/Ni(n,x..gamma..). A good estimate of the total inelastic scatterin… more

Date: January 1, 1985

Creator: Larson, D.C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Description of evaluation for /sup 50,52,53,54/Cr performed for ENDF/B-VI

Isotopic evaluations for /sup 50,52,53,54/Cr performed for ENDF/B-VI are briefly reviewed. The evaluations are based on analysis of experimental data and results of model calculations which reproduce the experimental data. Evaluated data are given for neutron induced reaction cross sections, angular and energy distributions, and for gamma-ray production cross sections associated with the reactions. File 6 formats are used to represent energy-angle correlated data and recoil spectra. Uncertainty… more

Date: January 1, 1987

Creator: Larson, D.C.; Hetrick, D.M. & Fu, C.Y.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Description of evaluations for /sup 58,60,61,62,64/Ni performed for ENDF/B-VI

Isotopic evaluations for /sup 58,50,61,62,64/Ni performed for ENDF/B-VI are briefly reviewed. The evaluations are based on analysis of experimental data and results of model calculations which reproduce the experimental data. Evaluated data are given for neutron induced reaction cross sections, angular and energy distributions, and for gamma-ray production cross sections associated with the reactions. File 6 formats are used to represent energy-angle correlated data and recoil spectra. Uncertai… more

Date: January 1, 1987

Creator: Larson, D.C.; Hetrick, D.M. & Fu, C.Y.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Description of evaluation of /sup nat/Pb performed for ENDF/B-VI

An evaluation of data for neutron induced reactions on natural lead was performed for ENDF/B-VI and is briefly reviewed. The evaluation is based on experimental data and results of model calculations which reproduce the experimental data. Evaluated data are given for neutron induced reaction cross sections, angular and energy distributions, and for gamma-ray production cross sections associated with the reactions. File 6 formats are used to represent energy-angle correlated data. Uncertainty fi… more

Date: January 1, 1987

Creator: Larson, D.C. & Fu, C.Y.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Experimental and calculated excitation functions for discrete-line gamma-ray production due to 1-40 MeV neutron interactions with sup 56 Fe

Measuring cross sections for gamma-ray production from tertiary reactions is one of the ways to gain experimental information about these reactions. To this end, inelastic and other nonelastic neutron interactions with {sup 56}Fe have been studied for incident neutron energies between 0.8 and 41 MeV. An iron sample isotopically enriched in the mass 56 isotope was used. Gamma rays representing 70 transitions among levels in residual nuclei were identified, and production cross sections were dedu… more

Date: January 1, 1991

Creator: Dickens, J.K.; Fu, C.Y.; Hetrick, D.M.; Larson, D.C. & Todd, J.H.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Neutron emission spectra induced by 14-MeV neutrons from the Evaluated Nuclear Data File (ENDF/B-V): a critical review

Neutron emission spectra induced by 14.6-MeV incident neutrons, retrieved from ENDF/B-V, are graphically compared with experimental data by Hermsdorf et al. and Clayeux and Voignier. The elements selected for the comparisons include Na, Mg, Al, Si, Ca, Ti, V, Cr, Fe, Ni, Cu, Nb, W, and Pb. In addition to comparing the evaluated total neutron emission spectra with experimental data, individually evaluated spectra from contributing reactions are presented. Only a few of the evaluated spectra were… more

Date: January 1, 1979

Creator: Hetrick, D.M.; Larson, D.C. & Fu, C.Y.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Description of evaluation for /sup 63,65/Cu for ENDF/B-VI

Isotopic evaluations for /sup 63,65/Cu performed for ENDF/B-VI are briefly reviewed. The evaluations are based on analysis of experimental data and results of model calculations which reproduce the experimental data. Evaluated data are given for neutron-induced reaction cross sections, angular and energy distributions, and for gamma-ray production cross sections associated with the reactions. File 6 formats are used to represent energy-angle correlated data and recoil spectra. Uncertainty files… more

Date: January 1, 1987

Creator: Larson, D.C.; Hetrick, D.M. & Fu, C.Y.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Some notes on the calculation of energy-angle correlated distributions with TNG and their representation in File 6 formats

The model code TNG has been extensively used in evaluation work of structural materials for ENDF/B-VI performed at Oak Ridge National Laboratory. A new aspect of ENDF/B-VI is the use of File 6 formats for energy-angle correlated data. Such data are generally calculated, anchored by experimental data. In this informal note we outline how the TNG results are calculated and entered in the File 6 formats. 4 refs.

Date: January 1, 1987

Creator: Larson, D.C.; Fu, C.Y. & Hetrick, D.M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Calculated neutron-induced cross sections for /sup 63,65/Cu /sup 58,60/Ni, and /sup 52/Cr from 1 to 20 MeV and comparisons with experiments

Nuclear model codes were used to compute cross sections for neutron-induced reactions on /sup 63,65/Cu, /sup 58,60/Ni, and /sup 52/Cr for incident energies from 1 to 20 MeV. The input parameters for the model codes determined through analysis of experimental data in this energy region. The models used, the input data, the resulting calculations, and comparisons with measured data are discussed. 15 refs.

Date: January 1, 1985

Creator: Hetrick, D.M.; Fu, C.Y. & Larson, D.C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

International evaluation cooperation Task 1. 1: Intercomparison of evaluated files for sup 52 Cr, sup 56 Fe, and sup 58 Ni

The cross sections and energy and angular distributions in the JENDL-3, JEF-2/EFF-2, and ENDF/B-VI evaluations for {sup 52}Cr, {sup 56}Fe, and {sup 58}Ni are compared graphically. The purpose is to understand the reasons for observed discrepancies among the evaluations, and to suggest recommendations for improvements. The accomplishments to date are presented.

Date: January 1, 1991

Creator: Fu, C.Y.; Larson, D.C.; Hetrick, D.M. (Oak Ridge National Lab., TN (USA)); Vonach, H. (Vienna Univ. (Austria)); Kopecky, J. (Netherlands Energy Research Foundation, Petten (Netherlands)); Iijima, S. (Toshiba Corp., Kawasaki (Japan). Nuclear Engineering Lab.) et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

ENDF/B-VI nuclear data evaluations for fusion applications

The next release of the ENDF/B data library planned for 1989 contains improved data evaluations of interest to the fusion neutronics community. New data formats permit inclusion of energy-angle correlated particle emission spectra and recoil nucleus energy spectra. Enhanced formats for covariance information have been developed. Many new isotopic evaluations will lead to improved energy conservation and kerma factor calculations. Improved nuclear model calculations will provide reliable particl… more

Date: January 1, 1988

Creator: Dunford, C.L.; Larson, D.C. & Young, P.G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Cross sections for production of 70 discrete-energy gamma rays created by neutron interactions with sup 56 Fe for E sub n to 40 MeV: Tabulated data

Inelastic and nonelastic neutron interactions with {sup 56}Fe have been studied for incident neutron energies between 0.8 and 41 MeV. An iron sample isotopically enriched in the mass 56 isotope was used. Gamma rays representing 70 transitions among levels in residual nuclei were identified, and production cross sections were deduced. The reactions studied were {sup 56}Fe(n,n{prime}){sup 56}Fe, {sup 56}Fe(n,p){sup 56}Mn, {sup 56}Fe(n,2n){sup 55}Fe, {sup 56}Fe(n,d + n,np){sup 55}Mn, {sup 56}Fe(n,… more

Date: September 1, 1990

Creator: Dickens, J.K.; Todd, J.H. & Larson, D.C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Measurement of the neutron total cross section of natural magnesium from 9 keV to 39 MeV. [Tables, resonance]

The neutron transmission through a 5.09-cm sample of natural magnesium was measured for neutron energies between 9 keV and 39 MeV. The Oak Ridge Electron Linear Accelerator (ORELA) was used to provide the neutrons, which were detected at the 200-m flight path by a NE-110 proton recoil detector. The experimental results are tabulated and compared with the total cross section in the ENDF/B-IV file for magnesium.

Date: June 1, 1978

Creator: Larson, D.C.; Harvey, J.A.; Hill, N.W. & Weigmann, H.

Item Type: Report

Partner: UNT Libraries Government Documents Department