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DOE OSTI · 2475569

MCNPs Easy Sources for (α,n) (MESA):Verification with Sources4c

Bates, Cameron Russell
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Abstract

MESA is intended to be a direct re-implementation of the algorithms documented in the Sources manual in C++. However, some fundamental changes to the computational structure and logic were made to avoid the use of goto, require consistency in input definition, and reduce computational approximations in later steps of three-layer problems. In addition, MESA uses α-decay information from ISC libraries (based on ENDF). In most cases, differences between Sources4c and MESA are dominated by differences in decay energy spectra and intensities. To verify this we have reproduced 6 problems that are documented examples or samples in Sources4c. These problems cover the three types of problems MESA currently supports: homogeneous, interface, and three-layer.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICS97 MATHEMATICS AND COMPUTING

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Bates, Cameron Russell. 2024-10-26. MCNPs Easy Sources for (α,n) (MESA):Verification with Sources4c. https://doi.org/10.2172/2475569

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