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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).”
Jacques Rognon
Nuclear Science and Engineering | Volume 30 | Number 1 | October 1967 | Pages 109-121
Technical Paper | doi.org/10.13182/NSE67-A17248
Articles are hosted by Taylor and Francis Online.
In this paper fast-fission effects in lattices with cluster elements are treated by dividing the cluster into concentric annuli and homogenizing each ring by means of the subcell method. Each annular zone is analyzed separately, and the influence of neighboring zones is described by in- and out-currents at the zone boundaries. Consistency of cross sections is checked in the simple case of an isolated rod in air. Backscattering and cluster-cluster interaction effects are taken into account and an extensive comparison is made between theoretical and experimental fission ratios. Finally, a new definition of ε is proposed, which is more consistent with the definition of p and combines all fast events in ε . EPSICH, a program based on this theory, calculates a complete case in a few tenths of a second on a CDC-1604, which justifies its use for optimalization studies.