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DOE OSTI · 2563101

MCNP® Code Version 6.3.1 Release Notes

Rising, Michael Evan [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000287122427)·Armstrong, Jerawan Chudoung [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000246811330)·Bolding, Simon R. [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000182961304)·Bull, Jeffrey S. [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000338642503)·Clark, Alexander R. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)]·Frederick, Cole Spencer [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)]·Giron, Jesse Frank [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000301185951)·Grieve, Avery S. [Commonwealth Fusion Systems, Cambridge, MA (United States)]·Haeck, Wim [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000188976603)·Jones, Fred Burke [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)]·Josey, Colin James [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000232105806)·Kulesza, Joel A. [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000226696339)·Lively, Michael Aaron [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000165119852)·Swaminarayan, Sriram [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000318095231)·Sweezy, Jeremy Ed [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:000000034847470X)·Weaver, Colin Andrew [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000263334185)·Zukaitis, Anthony J. [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)]
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Abstract

The Monte Carlo N-Particle® (MCNP® ) code is a general-purpose, continuous-energy, generalized-geometry, time-dependent, radiation transport code developed by the MCNP development team. MCNP calculations provide predictive capabilities that can replace expensive or impossible-to-perform experiments. Specific application problems include simulations of experimental diagnostics, intrinsic radiation, radiation detection and measurement, criticality safety, nuclear threat reduction and response, radiation health protection, nuclear weapons effects, and nuclear forensics. This MCNP code, version 6.3.1, follows the MCNP6.3.0 version. Since the release of MCNP6.3.0, a variety of bug fixes and code enhancements have been completed for MCNP6.3.1. A few new features have also been added to this release to support both ongoing research and the release of the latest ENDF/B-VIII.1 nuclear data library. The MCNP code, version 6.3.1, theory and user input information is documented in MCNP® Code Version 6.3.1 Theory & User Manual, the build guidance for various platforms is documented in MCNP® Code Version 6.3.1 Build Guide, and the verification and validation testing for various application benchmark test suites is documented in MCNP® Code Version 6.3.1 Verification & Validation Testing.

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Rising, Michael Evan [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000287122427), Armstrong, Jerawan Chudoung [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000246811330), Bolding, Simon R. [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000182961304), Bull, Jeffrey S. [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000338642503), Clark, Alexander R. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)], Frederick, Cole Spencer [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)], Giron, Jesse Frank [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000301185951), Grieve, Avery S. [Commonwealth Fusion Systems, Cambridge, MA (United States)], Haeck, Wim [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000188976603), Jones, Fred Burke [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)], Josey, Colin James [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000232105806), Kulesza, Joel A. [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000226696339), Lively, Michael Aaron [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000165119852), Swaminarayan, Sriram [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000318095231), Sweezy, Jeremy Ed [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:000000034847470X), Weaver, Colin Andrew [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000263334185), Zukaitis, Anthony J. [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)]. 2025-04-22. MCNP® Code Version 6.3.1 Release Notes. https://doi.org/10.2172/2563101

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