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DOE OSTI · 2349114

Contributions for ENDF/B-VIII.1 Paper

Neudecker, D.·Kleedtke, N.·Kahler, A. C.·Casperson, R. J.·Lovell, A.·Gibson, N.·Marshall, W. J.·Parsons, K.·Talou, P.
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Abstract

It was discussed at WANDA2020 that some issues were found by the community and users in ENDF/B-VIII.0 covariances after their release. It was mentioned that one issue in testing ENDF/B-VIII.0 covariances was that they were provided by evaluators too late in the β-release phases that insufficient time for thorough testing was available. Therefore, the executive committee requested that first nuclear data covariances should already be delivered for ENDF/B-VIII.1β 1 in February 2023—about half a year earlier than was the case for ENDF/B-VIII.0. This additional time allowed for more stringent testing with LANL’s ENDFtk and CovVal codes, and ORNL’s AMPX code during the release phases. The LLNL covariance testing employed a combination of NJOY, empy tools from EMPIRE, and x4i.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICSCovariancesFissionNuclear Criticality Safety Program (NCSP)Nuclear DataValidation

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Neudecker, D., Kleedtke, N., Kahler, A. C., Casperson, R. J., Lovell, A., Gibson, N., Marshall, W. J., Parsons, K., Talou, P.. 2024-04-02. Contributions for ENDF/B-VIII.1 Paper. https://doi.org/10.2172/2349114

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