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arXiv · 2610.25117

MACE: Multigroup-Multiangle Integrated Thermal Compton Scattering Kernel

Itamar Giron·Menahem Krief·Elad Steinberg
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Abstract

We present a comprehensive set of accurate Compton-scattering tables for use in multigroup, multiangle radiation-transport calculations. The tables contain the exact thermal Compton kernel integrated over incident-energy groups, scattered-energy groups, and angular bins. To generate them, we develop a deterministic integration method in which the pointwise kernel is evaluated with a robust numerical treatment that remains accurate across challenging regions of parameter space. The multidimensional integrals are computed using nested quadratures whose panels adapt to the Compton recoil ridge, its thermal broadening, and the nearly elastic forward-scattering boundary layer. We validate the tabulated results against published kernel profiles, angular and energy moments, mean free paths, multigroup redistribution data, and an independent Monte Carlo estimator. The resulting tables provide the radiation-transport community with accurate, reproducible, and readily usable Compton redistribution matrices and angular moments.

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Itamar Giron, Menahem Krief, Elad Steinberg. 2026-10-18. MACE: Multigroup-Multiangle Integrated Thermal Compton Scattering Kernel. https://arxiv.org/abs/2610.25117

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