Calculated covariance matrices for fission product yields using BeoH
Fission product yields (FPY) are important for a variety of applications (reactor neutronics, spent fuel, dosimetry, radiochemistry, etc.) and are currently included in many of the evaluated libraries around the world. The FPYs in the current US evaluation, ENDF/B-VIII.0, are mainly based on the 199...
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| Format: | Article |
| Language: | English |
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EDP Sciences
2023-01-01
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| Series: | EPJ Web of Conferences |
| Online Access: | https://www.epj-conferences.org/articles/epjconf/pdf/2023/07/epjconf_cw2023_00018.pdf |
| _version_ | 1797850689650556928 |
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| author | Lovell A. E. Kawano T. Talou P. |
| author_facet | Lovell A. E. Kawano T. Talou P. |
| author_sort | Lovell A. E. |
| collection | DOAJ |
| description | Fission product yields (FPY) are important for a variety of applications (reactor neutronics, spent fuel, dosimetry, radiochemistry, etc.) and are currently included in many of the evaluated libraries around the world. The FPYs in the current US evaluation, ENDF/B-VIII.0, are mainly based on the 1994 evaluation of England and Rider and have only had slight updates—such as the inclusion of a 2 MeV point for 239Pu—since their development. Additionally, only mean values and uncertainties are included in the evaluation, not full correlations. Los Alamos National Laboratory, in collaboration with several other institutes, has been working on an updated evaluation for the FPYs of 239Pu(n,f), 235U(n,f), 238U(n,f), and 252Cf(sf) using the deterministic, Hauser-Feshbach, fission fragment decay code, BeoH. BeoH calculates the FPYs consistently with many other prompt and delayed fission observables, explicitly taking into account multi-chance fission and ensuring consistency between observables. In addition to providing updated means and uncertainties for the FPYs on a pointwise energy grid from thermal to 20 MeV, we calculate correlations between all FPYs at each incident energy and across incident energies. Here, we discuss the development of these covariance matrices, differences in the correlations between FPYs based on the parameters that are included in the model optimization, and correlations across incident energies for neutron-induced fission. |
| first_indexed | 2024-04-09T19:05:30Z |
| format | Article |
| id | doaj.art-1eecd84caa844c779dab43206ed04e9d |
| institution | Directory Open Access Journal |
| issn | 2100-014X |
| language | English |
| last_indexed | 2024-04-09T19:05:30Z |
| publishDate | 2023-01-01 |
| publisher | EDP Sciences |
| record_format | Article |
| series | EPJ Web of Conferences |
| spelling | doaj.art-1eecd84caa844c779dab43206ed04e9d2023-04-07T09:02:20ZengEDP SciencesEPJ Web of Conferences2100-014X2023-01-012810001810.1051/epjconf/202328100018epjconf_cw2023_00018Calculated covariance matrices for fission product yields using BeoHLovell A. E.0Kawano T.1Talou P.2Los Alamos National LaboratoryLos Alamos National LaboratoryLos Alamos National LaboratoryFission product yields (FPY) are important for a variety of applications (reactor neutronics, spent fuel, dosimetry, radiochemistry, etc.) and are currently included in many of the evaluated libraries around the world. The FPYs in the current US evaluation, ENDF/B-VIII.0, are mainly based on the 1994 evaluation of England and Rider and have only had slight updates—such as the inclusion of a 2 MeV point for 239Pu—since their development. Additionally, only mean values and uncertainties are included in the evaluation, not full correlations. Los Alamos National Laboratory, in collaboration with several other institutes, has been working on an updated evaluation for the FPYs of 239Pu(n,f), 235U(n,f), 238U(n,f), and 252Cf(sf) using the deterministic, Hauser-Feshbach, fission fragment decay code, BeoH. BeoH calculates the FPYs consistently with many other prompt and delayed fission observables, explicitly taking into account multi-chance fission and ensuring consistency between observables. In addition to providing updated means and uncertainties for the FPYs on a pointwise energy grid from thermal to 20 MeV, we calculate correlations between all FPYs at each incident energy and across incident energies. Here, we discuss the development of these covariance matrices, differences in the correlations between FPYs based on the parameters that are included in the model optimization, and correlations across incident energies for neutron-induced fission.https://www.epj-conferences.org/articles/epjconf/pdf/2023/07/epjconf_cw2023_00018.pdf |
| spellingShingle | Lovell A. E. Kawano T. Talou P. Calculated covariance matrices for fission product yields using BeoH EPJ Web of Conferences |
| title | Calculated covariance matrices for fission product yields using BeoH |
| title_full | Calculated covariance matrices for fission product yields using BeoH |
| title_fullStr | Calculated covariance matrices for fission product yields using BeoH |
| title_full_unstemmed | Calculated covariance matrices for fission product yields using BeoH |
| title_short | Calculated covariance matrices for fission product yields using BeoH |
| title_sort | calculated covariance matrices for fission product yields using beoh |
| url | https://www.epj-conferences.org/articles/epjconf/pdf/2023/07/epjconf_cw2023_00018.pdf |
| work_keys_str_mv | AT lovellae calculatedcovariancematricesforfissionproductyieldsusingbeoh AT kawanot calculatedcovariancematricesforfissionproductyieldsusingbeoh AT taloup calculatedcovariancematricesforfissionproductyieldsusingbeoh |