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