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Title: Calculation of the minimum critical mass of fissile nuclides

Abstract

The OB-1 method for the calculation of the minimum critical mass of fissile actinides in metal/water systems was described in a previous paper. A fit to the calculated minimum critical mass data using the extended criticality parameter is the basis of the revised method. The solution density (grams/liter) for the minimum critical mass is also obtained by a fit to calculated values. Input to the calculation consists of the Maxwellian averaged fission and absorption cross sections and the thermal values of nubar. The revised method gives more accurate values than the original method does for both the minimum critical mass and the solution densities. The OB-1 method has been extended to calculate the uncertainties in the minimum critical mass for 12 different fissile nuclides. The uncertainties for the fission and capture cross sections and the estimated nubar uncertainties are used to determine the uncertainties in the minimum critical mass, either in percent or grams. Results have been obtained for U-233, U-235, Pu-236, Pu-239, Pu-241, Am-242m, Cm-243, Cm-245, Cf-249, Cf-251, Cf-253, and Es-254. Eight of these 12 nuclides are included in the ANS-8.15 standard.

Authors:
 [1];  [2]
  1. Oak Ridge National Laboratory (ORNL)
  2. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1036587
DOE Contract Number:  
DE-AC05-00OR22725
Resource Type:
Journal Article
Journal Name:
Nuclear Science and Engineering
Additional Journal Information:
Journal Volume: 158; Journal Issue: 2; Journal ID: ISSN 0029-5639
Country of Publication:
United States
Language:
English
Subject:
07 ISOTOPES AND RADIATION SOURCES; ABSORPTION; ACTINIDES; CRITICAL MASS; CRITICALITY; CROSS SECTIONS; FISSION; ISOTOPES

Citation Formats

Wright, R Q, and Hopper, Calvin Mitchell. Calculation of the minimum critical mass of fissile nuclides. United States: N. p., 2008. Web.
Wright, R Q, & Hopper, Calvin Mitchell. Calculation of the minimum critical mass of fissile nuclides. United States.
Wright, R Q, and Hopper, Calvin Mitchell. 2008. "Calculation of the minimum critical mass of fissile nuclides". United States.
@article{osti_1036587,
title = {Calculation of the minimum critical mass of fissile nuclides},
author = {Wright, R Q and Hopper, Calvin Mitchell},
abstractNote = {The OB-1 method for the calculation of the minimum critical mass of fissile actinides in metal/water systems was described in a previous paper. A fit to the calculated minimum critical mass data using the extended criticality parameter is the basis of the revised method. The solution density (grams/liter) for the minimum critical mass is also obtained by a fit to calculated values. Input to the calculation consists of the Maxwellian averaged fission and absorption cross sections and the thermal values of nubar. The revised method gives more accurate values than the original method does for both the minimum critical mass and the solution densities. The OB-1 method has been extended to calculate the uncertainties in the minimum critical mass for 12 different fissile nuclides. The uncertainties for the fission and capture cross sections and the estimated nubar uncertainties are used to determine the uncertainties in the minimum critical mass, either in percent or grams. Results have been obtained for U-233, U-235, Pu-236, Pu-239, Pu-241, Am-242m, Cm-243, Cm-245, Cf-249, Cf-251, Cf-253, and Es-254. Eight of these 12 nuclides are included in the ANS-8.15 standard.},
doi = {},
url = {https://www.osti.gov/biblio/1036587}, journal = {Nuclear Science and Engineering},
issn = {0029-5639},
number = 2,
volume = 158,
place = {United States},
year = {Tue Jan 01 00:00:00 EST 2008},
month = {Tue Jan 01 00:00:00 EST 2008}
}