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DOE OSTI Β· 2999959

On MCNP Stochastic Volume Estimation Normalization

Kulesza, Joel A. [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000226696339)
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Abstract

This paper resolves a perennial point of confusion regarding the source-weighting normalization factor recommended in the MCNP manual (πœ‹β’π‘Ÿ 2 ) to stochastically estimate the volume of a region within an enclosing inward-directed spherical surface source with radius π‘Ÿ. The normalization factor arises from the relationship between a sphere’ s mean chord length, its volume, and the values estimated by MCNP track-length tallies. A brief derivation is given that relates these quantities and results in the stated normalization. The correctness of this factor is demonstrated by estimating the volume of a variety of convex and nonconvex volumes. A heuristic demonstration of how biasing the inward-directed source reduces the statistical uncertainty of the stochastic volume estimate is also given, but a rigorous analysis of this improvement is left as future work.

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42 ENGINEERING97 MATHEMATICS AND COMPUTING99 GENERAL AND MISCELLANEOUSMCNPstochastic volume estimation

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Kulesza, Joel A. [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000226696339). 2025-06-06. On MCNP Stochastic Volume Estimation Normalization. https://doi.org/10.1080/00295639.2025.2483123

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