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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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NNSA awards BWXT $1.5B defense fuels contract
The Department of Energy’s National Nuclear Security Administration has awarded BWX Technologies a contract valued at $1.5 billion to build a Domestic Uranium Enrichment Centrifuge Experiment (DUECE) pilot plant in Tennessee in support of the administration’s efforts to build out a domestic supply of unobligated enriched uranium for defense-related nuclear fuel.
D. R. Alexander, Y. K. Peng
Nuclear Science and Engineering | Volume 70 | Number 2 | May 1979 | Pages 184-191
Technical Paper | doi.org/10.13182/NSE79-A19651
Articles are hosted by Taylor and Francis Online.
The time-dependent unseparated six delayed neutron group yields are calculated for thermal-neutron fission of 235U. These calculations are based on a recent reference set of delayed neutron precursors, available fission data, and fission systematics. The unseparated calculated time-dependent group yields are compared with separated group yields (groups based on half-life values) and the experimental unseparated group yields. The comparisons indicate the magnitude of the error involved when separated group yields are used for evaluating the accuracy of delayed neutron data. A total delayed neutron yield of 160.62 ± 11.52 per 104 fissions was obtained for thermal-neutron fission of 235U.
