The MCNP®6 code: A decade of progress

Rising, Michael E.; Armstrong, Jerawan C.; Bolding, Simon R.; Bull, Jeffrey S.; Casswell, Laura; Clark, Alexander R.; Forster, R. Arthur; Frederick, Cole S.; Giron, Jesse F.; Jones, Fred B.; Josey, Colin J.; Kelley, Timothy M.; Kulesza, Joel A.; Lively, Michael A.; Little, Robert C.; Swaminarayan, Sriram; Sweezy, Jeremy E.; Vaquer, Pablo A.; Weaver, Colin A.; Zukaitis, Anthony J.

doi:10.1051/epjn/2025003

The MCNP^®6 code: A decade of progress

Journal Article · Fri Mar 28 00:00:00 EDT 2025 · EPJ Nuclear Sciences and Technologies

DOI:https://doi.org/10.1051/epjn/2025003· OSTI ID:2556797

^[1]; Armstrong, Jerawan C. ^[1]; Bolding, Simon R. ^[1]; Bull, Jeffrey S. ^[1]; Casswell, Laura ^[1]; ^[1]; Forster, R. Arthur ^[1]; Frederick, Cole S. ^[1]; ^[1]; Jones, Fred B. ^[1]; Josey, Colin J. ^[1]; Kelley, Timothy M. ^[1]; ^[1]; ^[1]; Little, Robert C. ^[1]; Swaminarayan, Sriram ^[1]; ^[1]; Vaquer, Pablo A. ^[1]; ^[1]; Zukaitis, Anthony J. ^[1]

Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)

After several years of effort involved in merging the Los Alamos National Laboratory MCNP5 and MCNPX codes, in 2013 the first production release of version 6 of the Monte Carlo N-Particle^®, or MCNP^®, code MCNP6.1 was distributed publicly. Since then, three significant releases have been issued: MCNP6.1.1beta in 2014, MCNP6.2 in 2018, and MCNP6.3 in 2023. While each release always contains new features, code enhancements, and bug fixes, each version has had a different primary focus, ranging from improved calculational efficiency to new powerful utilities and tools, to software modernization of the code base. With all that has been learned over the first decade of the MCNP6 code, continuous progress is being made toward a modernized, general-purpose Monte Carlo radiation transport code that remains a trusted resource for the global community of practitioners. This paper describes these first 10+ years of the MCNP6 code and its continually improving data libraries, and gives some insight into how the next decade is expected to unfold.

View Accepted Manuscript (DOE)

Research Organization:: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)

Sponsoring Organization:: USDOE National Nuclear Security Administration (NNSA), Nuclear Criticality Safety Program (NCSP)

Grant/Contract Number:: 89233218CNA000001

OSTI ID:: 2556797

Report Number(s):: LA-UR--24-28294

Journal Information:: EPJ Nuclear Sciences and Technologies, Journal Name: EPJ Nuclear Sciences and Technologies Vol. 11; ISSN 2491-9292

Publisher:: EDP SciencesCopyright Statement

Country of Publication:: United States

Language:: English

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