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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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ANS joins others in seeking to discuss SNF/HLW impasse
The American Nuclear Society joined seven other organizations to send a letter to Energy Secretary Christopher Wright on July 8, asking to meet with him to discuss “the restoration of a highly functioning program to meet DOE’s legal responsibility to manage and dispose of the nation’s commercial and legacy defense spent nuclear fuel (SNF) and high-level radioactive waste (HLW).”
E. C. Miller, J. K. Mattingly, S. D. Clarke, C. J. Solomon, B. Dennis, A. Meldrum, S. A. Pozzi
Nuclear Science and Engineering | Volume 176 | Number 2 | February 2014 | Pages 167-185
Technical Paper | doi.org/10.13182/NSE12-53
Articles are hosted by Taylor and Francis Online.
Simulations of neutron multiplicity measurements of a highly multiplicative plutonium sphere measured with a moderated array of 3He proportional counters have consistently overpredicted the mean and variance of the measured multiplicity distribution. In contrast, identical experiments using a 252Cf source have been accurately simulated. This paper outlines a sensitivity analysis of several key parameters that could account for the overprediction in the simulation of the plutonium sphere. Parameters that were analyzed include source-detector distance, detector dead time, variations in density and volume of the plutonium, and the value of for v̅ 239Pu-induced fission. Of these parameters, the only factor that accounted for the overprediction within reasonable bounds was a change in the value of the 239Pu v̅. The sensitivity analysis showed that a small change (1.14% reduction) in the value of v̅ dramatically improved the simulated results.