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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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Surplus plutonium for power reactor fuel: What’s on offer
The Department of Energy has a plan for private companies to “dispose of surplus plutonium”—about 19.7 metric tons in both oxide and metal forms—by “making the materials available for advanced nuclear technologies.” A Surplus Plutonium Utilization Program request for applications (RFA) issued October 21 describes the plutonium on offer, and the “thresholds” prospective applicants must meet.
N. M. Larson, L. C. Leal, H. Derrien
Nuclear Science and Engineering | Volume 131 | Number 2 | February 1999 | Pages 254-266
Technical Paper | doi.org/10.13182/NSE99-A2032
Articles are hosted by Taylor and Francis Online.
Neutron time-of-flight experiments have long been used to determine resonance parameters. Those resonance parameters have then been used in calculations of integral quantities such as Maxwellian averages or resonance integrals, and results of those calculations in turn have been used as a criterion for acceptability of the resonance analysis. However, the calculations were inadequate because covariances on the parameter values were not included in the calculations. An effort to correct for that deficiency is documented: The R-matrix analysis code SAMMY has been modified to include integral quantities of importance, directly within the resonance parameter analysis, to determine the best fit to both differential (microscopic) and integral (macroscopic) data simultaneously. This modification was implemented because it is expected to have an impact on the intermediate energy range that is important for criticality safety applications.