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DOE OSTI · 1632667

TRT Compton Scattering Data: Comparisons between LLNL and LANL: Pointwise

Till, Andrew Thomas·Long, Kendra Phyllis
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Abstract

This memo is one of a pair of reports comparing Compton scattering data in the context of thermal radiation transport (TRT). This document focuses on Pointwise (PW) data while the other report focuses on Multigroup (MG) data. These complementary analyses, via PW comparisons, show if the same physics are used and if fundamental bugs are present, and, via MG comparisons, quantify macroscopic Compton effects such as mean amplification factors. No averaging of Compton data over photon energy is done for the PW comparisons, while lab-dependent numerical resolution choices become relevant for the MG comparisons. This document plots and quantifies differences in PW Compton scattering data between LANL and LLNL for four disparate temperatures on a logarithmically-spaced energy grid. PW comparisons means we use the received LLNL data as-is, without any averaging or integration over energy. In addition to LANL-to-LLNL comparisons, we investigate the impact of numerical choices on LANL PW data. For the purposes of this comparison, we neglect induced scattering.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICS97 MATHEMATICS AND COMPUTINGCompton scatteringdatathermal radiation transport

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Till, Andrew Thomas, Long, Kendra Phyllis. 2020-05-27. TRT Compton Scattering Data: Comparisons between LLNL and LANL: Pointwise. https://doi.org/10.2172/1632667

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