Impact of MCNP Unresolved Resonance Probability-Table Treatment on ²³³U Benchmarks

Conference · Sun Jun 06 00:00:00 EDT 1999

OSTI ID:350950

Mosteller, Russell D. ^[1]

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

Previous versions of the MCNP Monte Carlo code, up through and including MCNP4B, have not accurately modeled neutron self-shielding effects in the unresolved resonance energy region. Recently, a probability-table treatment has been incorporated into an intermediate version called MCNP4XS, and compatible continuous-energy cross-section libraries have been developed for 27 different isotopes. Preliminary results for a variety of uranium and plutonium benchmarks have been presented previously, and this paper extends those results to include several ²³³U benchmarks. The objective of the current study is to assess the reactivity impact of the probability-table treatment on ²³³U systems.

• 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)
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 350950
• Report Number(s): LA-UR--99-152; CONF-990605--; ON: DE99002733
• Country of Publication: United States
• Language: English

Related Subjects

22 GENERAL STUDIES OF NUCLEAR REACTORS
97 MATHEMATICS AND COMPUTING
99 GENERAL AND MISCELLANEOUS
BENCHMARKS
CROSS SECTIONS
LIBRARIES
M CODES
MCNP4XS
Monte Carlo Code
Nuclear Criticality Safety Program (NCSP)
PROBABILITY
REACTIVITY
RESONANCE NEUTRONS
SELF-SHIELDING
URANIUM 233
ZERO POWER REACTORS