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DOE OSTI · 1993797

PMT-004 Validation Testing for Thermal Scattering Laws and Some Interesting Temperature-Dependent Implications [Slides]

Percher, Catherine·Norris, Jesse
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Abstract

This presentation finds that PMT-004 has four new benchmark cases highly sensitive to PE TSL (2 cases) and PMMA TSL (2 Cases). Additionally discovered was that the PE cases were well predicted using MCNP6.2 and ENDF/B-VIII.0. PMMA cases overpredicted by approximately 0.6-0.7% in k eff likely due to the lack of integral benchmarks sensitive to PMMA. The NCSU ENDF/B-VIII.1 PMMA TSL is an improvement over VIII.0. This was Accepted at last ICSBEP meeting pending comment resolution, should be published in 2024 version of the Handbook. It was found that temperature had a large impact on reactivity of the critical configuration. This has Implications for validation work for thermal cases- need to adjust TSL data to correct temperature as it can have hundreds of pcm effects for a few °C. Future thermal experiments should try and measure reactivity at multiple temperatures to add in data testing and benchmark adjustment.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICS97 MATHEMATICS AND COMPUTINGBenchmark CasesENDF/B-VIII.0K-EffectiveMCNP6.2Nuclear Criticality Safety Program (NCSP)PMT-004Temperature Impact

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Percher, Catherine, Norris, Jesse. 2023-04-26. PMT-004 Validation Testing for Thermal Scattering Laws and Some Interesting Temperature-Dependent Implications [Slides]. https://doi.org/10.2172/1993797

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