RMatrix Analysis of 238U High Resolution Neutron Transmissions and Capture Cross Sections in the Energy Range 0 keV to 20 keV
Abstract
The neutron resonance parameters of 238U were obtained from a SAMMY analysis of highresolution neutron transmission measurements and highresolution capture cross section measurements performed at the Oak Ridge Electron Linear Accelerator (ORELA) in the years 19701990 and from more recent transmission and capture cross section measurements performed at the Geel Linear Accelerator (GELINA). Compared with previous evaluations, the energy range for this resonance analysis was extended from 10 to 20 keV, taking advantage of the high resolution of the most recent ORELA transmission measurements. The experimental database and the method of analysis are described in this report. The neutron transmissions and the capture cross sections calculated with the resonance parameters are compared with the experimental data. A description is given of the statistical properties of the resonance parameters and of the recommended values of the average parameters. The new evaluation results in a slight decrease of the effective capture resonance integral and improves the prediction of integral thermal benchmarks by 70 to 200 pcm.
 Authors:
 ORNL
 Publication Date:
 Research Org.:
 Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
 Sponsoring Org.:
 USDOE National Nuclear Security Administration (NNSA)
 OSTI Identifier:
 959433
 DOE Contract Number:
 DEAC0500OR22725
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Nuclear Science and Engineering; Journal Volume: 161; Journal Issue: 2
 Country of Publication:
 United States
 Language:
 English
 Subject:
 43 PARTICLE ACCELERATORS; BENCHMARKS; CROSS SECTIONS; ELECTRONS; ENERGY RANGE; EVALUATION; LINEAR ACCELERATORS; NEUTRONS; R MATRIX; RESOLUTION; RESONANCE; RESONANCE INTEGRALS; Cross Sections; RMatrix; 238U High Resolution
Citation Formats
Derrien, Herve, Leal, Luiz C, and Larson, Nancy M. RMatrix Analysis of 238U High Resolution Neutron Transmissions and Capture Cross Sections in the Energy Range 0 keV to 20 keV. United States: N. p., 2009.
Web. doi:10.13182/NSE161131.
Derrien, Herve, Leal, Luiz C, & Larson, Nancy M. RMatrix Analysis of 238U High Resolution Neutron Transmissions and Capture Cross Sections in the Energy Range 0 keV to 20 keV. United States. doi:10.13182/NSE161131.
Derrien, Herve, Leal, Luiz C, and Larson, Nancy M. 2009.
"RMatrix Analysis of 238U High Resolution Neutron Transmissions and Capture Cross Sections in the Energy Range 0 keV to 20 keV". United States.
doi:10.13182/NSE161131.
@article{osti_959433,
title = {RMatrix Analysis of 238U High Resolution Neutron Transmissions and Capture Cross Sections in the Energy Range 0 keV to 20 keV},
author = {Derrien, Herve and Leal, Luiz C and Larson, Nancy M},
abstractNote = {The neutron resonance parameters of 238U were obtained from a SAMMY analysis of highresolution neutron transmission measurements and highresolution capture cross section measurements performed at the Oak Ridge Electron Linear Accelerator (ORELA) in the years 19701990 and from more recent transmission and capture cross section measurements performed at the Geel Linear Accelerator (GELINA). Compared with previous evaluations, the energy range for this resonance analysis was extended from 10 to 20 keV, taking advantage of the high resolution of the most recent ORELA transmission measurements. The experimental database and the method of analysis are described in this report. The neutron transmissions and the capture cross sections calculated with the resonance parameters are compared with the experimental data. A description is given of the statistical properties of the resonance parameters and of the recommended values of the average parameters. The new evaluation results in a slight decrease of the effective capture resonance integral and improves the prediction of integral thermal benchmarks by 70 to 200 pcm.},
doi = {10.13182/NSE161131},
journal = {Nuclear Science and Engineering},
number = 2,
volume = 161,
place = {United States},
year = 2009,
month = 1
}

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