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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).”
P. L. Reeder, R. A. Warner
Nuclear Science and Engineering | Volume 79 | Number 1 | September 1981 | Pages 56-64
Technical Paper | doi.org/10.13182/NSE81-A19042
Articles are hosted by Taylor and Francis Online.
Average energies of the delayed neutron spectra from 34 precursors have been compiled from the literature to give a set of best values. Average energies of six-group and equilibrium spectra are calculated by summing weighted values of the individual precursors. These calculated average energies are in reasonable agreement with the rather limited experimental data. Equilibrium delayed neutron spectra are calculated by summing spectra for individual precursors. The calculated equilibrium spectra are then compared to an approximate spectrum based on a Maxwellian distribution with just one parameter, the average energy. Sets of experimental spectra for individual precursors measured at two different laboratories are compared. The Maxwellian shape gives reasonable agreement with one set. The other set has more neutrons at low energy and does not fit a Maxwellian shape.