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DOE OSTI · 1907928

Data Testing with Zero Power Reactor (ZPR), Zero Power Physics Reactor (ZPPR), and New Thermal Epithermal eXperiments (TEX) Plutonium Benchmarks [Slides]

Percher, Catherine·Norris, Jesse·Kim, Soon·Heinrichs, David
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Abstract

This presentation states that new TSLs in ENDF/B-VIII.0 will reduce the overprediction of the library for the most moderated cases. The differences between VII.1 and VIII.0 are driven by the 239 Pu changes and are consistently higher for all configurations. The VIII.0 239 Pu thermal cross sections were specifically adjusted lower to better predict plutonium thermal solutions criticality benchmarks, yet they overpredict the TEX thermal configurations, moderated by PE. Other, smaller differences have been seen for 240 Pu and 56 Fe. PMM-002 has shown utility in testing cross sections over a wide range of neutron energies.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICSCritical BenchmarkEvaluated Nuclear Data File (ENDF)Integral ExperimentsNeutron EnergyNuclear Criticality Safety Program (NCSP)Technical Standards List (TSL)Thermal Cross Sections

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Percher, Catherine, Norris, Jesse, Kim, Soon, Heinrichs, David. 2020-12-02. Data Testing with Zero Power Reactor (ZPR), Zero Power Physics Reactor (ZPPR), and New Thermal Epithermal eXperiments (TEX) Plutonium Benchmarks [Slides]. https://doi.org/10.2172/1907928

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