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DOE OSTI · 1923296

COG Beta-Effective Benchmarks

Heinrichs, Dave·Lent, Ed·Zywiec, Will
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Abstract

COG 11.3 calculations with the “new method” using ENDF/B-VIII.0 data are shown to produce results with |C/E – 1| < 3σ in all cases, whereas the other methods produce a few minor outliers. Furthermore, the “new method” using ENDF/B-VIII.0 data is observed to produce “over” and “under” results consistent with 50/50 expectations whereas the other methods appear to be slightly over or under predicting. JEFF-3.3 results are slightly larger overall than ENDF/B-VIII.0 results. In all but a few cases, it is also observed that $F_d/F_t ≥ (vF)_d/(vF)_t ≥ 1 – (k_{prompt}/k_{eff})$ and all estimators produce equivalent results for the most thermal systems. In those other cases, this relation holds within the given statistics.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICSAnalytical MethodsBeta-effCritical AssembliesNuclear Criticality Safety Program (NCSP)

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Heinrichs, Dave, Lent, Ed, Zywiec, Will. 2022-12-20. COG Beta-Effective Benchmarks. https://doi.org/10.2172/1923296

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