Investigation of Inconsistent ENDF/BVII.1 Independent and Cumulative Fission Product Yields with Proposed Revisions
Abstract
A recent implementation of ENDF/BVII.1 independent fission product yields and nuclear decay data identified inconsistencies in the data caused by the use of updated nuclear schemes in the decay sublibrary that are not reflected in legacy fission product yield data. Recent changes in the decay data sublibrary, particularly the delayed neutron branching fractions, result in calculated fission product concentrations that do not agree with the cumulative fission yields in the library as well as with experimental measurements. To address these issues, a comprehensive set of independent fission product yields was generated for thermal and fission spectrum neutroninduced fission for {sup 235,238}U and {sup 239,241}Pu in order to provide a preliminary assessment of the updated fission product yield data consistency. These updated independent fission product yields were utilized in the ORIGEN code to compare the calculated fission product inventories with experimentally measured inventories, with particular attention given to the noble gases. Another important outcome of this work is the development of fission product yield covariance data necessary for fission product uncertainty quantification. The evaluation methodology combines a sequential Bayesian method to guarantee consistency between independent and cumulative yields along with the physical constraints on the independent yields. This work was motivatedmore »
 Authors:
 Publication Date:
 OSTI Identifier:
 22436788
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Nuclear Data Sheets; Journal Volume: 123; Conference: International workshop on nuclear data covariances, Santa Fe, NM (United States), 28 Apr  1 May 2014; Other Information: Copyright (c) 2014 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; COMPARATIVE EVALUATIONS; DATA COVARIANCES; DELAYED NEUTRONS; FISSION PRODUCTS; FISSION YIELD; NEUTRON REACTIONS; NUCLEAR DATA COLLECTIONS; NUCLEAR DECAY; PLUTONIUM 239 TARGET; PLUTONIUM 241 TARGET; URANIUM 235 TARGET; URANIUM 238 TARGET
Citation Formats
Pigni, M.T., Email: pignimt@ornl.gov, Francis, M.W., and Gauld, I.C.. Investigation of Inconsistent ENDF/BVII.1 Independent and Cumulative Fission Product Yields with Proposed Revisions. United States: N. p., 2015.
Web. doi:10.1016/J.NDS.2014.12.040.
Pigni, M.T., Email: pignimt@ornl.gov, Francis, M.W., & Gauld, I.C.. Investigation of Inconsistent ENDF/BVII.1 Independent and Cumulative Fission Product Yields with Proposed Revisions. United States. doi:10.1016/J.NDS.2014.12.040.
Pigni, M.T., Email: pignimt@ornl.gov, Francis, M.W., and Gauld, I.C.. 2015.
"Investigation of Inconsistent ENDF/BVII.1 Independent and Cumulative Fission Product Yields with Proposed Revisions". United States.
doi:10.1016/J.NDS.2014.12.040.
@article{osti_22436788,
title = {Investigation of Inconsistent ENDF/BVII.1 Independent and Cumulative Fission Product Yields with Proposed Revisions},
author = {Pigni, M.T., Email: pignimt@ornl.gov and Francis, M.W. and Gauld, I.C.},
abstractNote = {A recent implementation of ENDF/BVII.1 independent fission product yields and nuclear decay data identified inconsistencies in the data caused by the use of updated nuclear schemes in the decay sublibrary that are not reflected in legacy fission product yield data. Recent changes in the decay data sublibrary, particularly the delayed neutron branching fractions, result in calculated fission product concentrations that do not agree with the cumulative fission yields in the library as well as with experimental measurements. To address these issues, a comprehensive set of independent fission product yields was generated for thermal and fission spectrum neutroninduced fission for {sup 235,238}U and {sup 239,241}Pu in order to provide a preliminary assessment of the updated fission product yield data consistency. These updated independent fission product yields were utilized in the ORIGEN code to compare the calculated fission product inventories with experimentally measured inventories, with particular attention given to the noble gases. Another important outcome of this work is the development of fission product yield covariance data necessary for fission product uncertainty quantification. The evaluation methodology combines a sequential Bayesian method to guarantee consistency between independent and cumulative yields along with the physical constraints on the independent yields. This work was motivated to improve the performance of the ENDF/BVII.1 library for stable and longlived fission products. The revised fission product yields and the new covariance data are proposed as a revision to the fission yield data currently in ENDF/BVII.1.},
doi = {10.1016/J.NDS.2014.12.040},
journal = {Nuclear Data Sheets},
number = ,
volume = 123,
place = {United States},
year = 2015,
month = 1
}

A recent implementation of ENDF/BVII. independent fission product yields and nuclear decay data identified inconsistencies in the data caused by the use of updated nuclear scheme in the decay sublibrary that is not reflected in legacy fission product yield data. Recent changes in the decay data sublibrary, particularly the delayed neutron branching fractions, result in calculated fission product concentrations that are incompatible with the cumulative fission yields in the library, and also with experimental measurements. A comprehensive set of independent fission product yields was generated for thermal and fission spectrum neutron induced fission for ^{235,238}U and ^{239,241}Pu in order tomore »

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