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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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The when, where, why, and how of RIPB design
The American Nuclear Society’s Risk-informed, Performance-based Principles and Policy Committee (RP3C) held another presentation in its monthly Community of Practice (CoP) series.
Watch the full webinar here.
Takaaki Ohsawa, Franz-Josef Hambsch
Nuclear Science and Engineering | Volume 148 | Number 1 | September 2004 | Pages 50-54
Technical Paper | doi.org/10.13182/NSE04-A2440
Articles are hosted by Taylor and Francis Online.
Possible fluctuation in the delayed neutron yields (DNYs) in the resonance region was predicted on the basis of experimental data of mass distribution of fission fragments at resonances. Analyzed according to the multimodal random neck rupture model of fission, the small variations in the experimental mass distribution were attributed to fluctuations in the branching ratios to different modes of fission. Using the results of analysis of measured data for 235U and 239Pu, the DNYs were calculated for each resonance by the summation method, considering 271 precursors and evaluated data of delayed neutron emission probability. It was found that the DNYs should have local dips for 235U and spikes for 239Pu at resonances.