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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).”
L. W. Weston, J. H. Todd
Nuclear Science and Engineering | Volume 79 | Number 2 | October 1981 | Pages 184-196
Technical Paper | doi.org/10.13182/NSE81-A27407
Articles are hosted by Taylor and Francis Online.
The neutron capture cross section of 237Np was measured from 0.01 eV to 200 keV. The capture cross section was normalized at 0.0253 eV to a value of 180 ± 6 b derived from previous total cross-section measurements in the resonance region of neutron energies and the shape of the present data from 0.0253 eV to the resonance region. Resonance parameters were derived for the neutron energy region from 0.01 to 100 eV. Agreement with ENDF/B-V is poor in the thermal region (6.4%), excellent in the resonance region (∼2%) except for the 0.491-eV resonance, and good (∼5%) in the keV neutron energy region. An uncertainty analysis including a correlation matrix for group-averaged cross sections is presented. These results are important both for thermal and fast reactor applications and the calculation of 238Pu production, an intense alpha emitter.