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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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Leading the charge: INL’s role in advancing HALEU production
Idaho National Laboratory is playing a key role in helping the U.S. Department of Energy meet near-term needs by recovering HALEU from federal inventories, providing critical support to help lay the foundation for a future commercial HALEU supply chain. INL also supports coordination of broader DOE efforts, from material recovery at the Savannah River Site in South Carolina to commercial enrichment initiatives.
Masayoshi Sugimoto, Alan B. Smith, Peter T. Guenther
Nuclear Science and Engineering | Volume 97 | Number 3 | November 1987 | Pages 235-238
Technical Note | doi.org/10.13182/NSE87-A23505
Articles are hosted by Taylor and Francis Online.
The prompt fission neutron spectrum resulting from 239Pu fission induced by ∼0.55-MeV incident neutrons is measured from 1.0 to 10.0 MeV relative to that of 235U fission induced by the same incident energy neutrons. The measurements employ the time-of-flight technique. Energy-dependent ratios of the two spectra are deduced from the measured values. The experimentally derived ratio results are compared with those calculated from ENDF/B-V (revision 2) and with results of recent microscopic measurements. Using the ENDF/B-V 235U Watt parameters for the 235U spectrum, the experimental measurements imply a ratio of average fission spectrum energies of 239Pu/235U = 1.045 ± 0.003, compared to the value 1.046 calculated from ENDF/B-V (revision 2).
