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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).”
J. T. Mihalczo
Nuclear Science and Engineering | Volume 56 | Number 3 | March 1975 | Pages 271-290
Technical Paper | doi.org/10.13182/NSE75-3
Articles are hosted by Taylor and Francis Online.
The spatial distribution of the neutron importance in bare and natural-uranium-reflected uranium (∼93.2 wt% 235U) and plutonium (∼4.7 at % 240Pu) metal spheres was measured using 252Cf neutron sources. The spatial distribution of the fission density from activation measurements in the bare spheres and those previously measured for the reflected spheres are presented.Comparison of these distributions with those from S16 transport theory calculations showed that the measured and calculated results agreed very well for the bare spheres and in the central core of the reflected spheres. The disagreement in the natural uranium reflector increased with radius and attained values as large as ∼35% at the outer surface. The sensitivity of the calculations to the cross sections is examined.These measurements were undertaken to properly account for spatial effects in the point reactor kinetics description of Rossi-α measurements. The spatial-effects factors obtained from these measurements, which multiply the correlated amplitude of the Rossi-α measurement, were 1.123, 1.109, 1.163, and 1.214 for the bare uranium, bare plutonium, reflected uranium, and reflected plutonium spheres, respectively. The error in these values is ± 0.010.