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arXiv · 2212.08943

Consideration of memory of spin and parity in the fissioning compound nucleus by applying the Hauser-Feshbach fission fragment decay model to photonuclear reactions

Toshihiko Kawano·Amy E. Lovell·Shin Okumura·Hirokazu Sasaki·Ionel Stetcu·Patrick Talou
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Abstract

Prompt and $β$-delayed fission observables, such as the average number of prompt and delayed neutrons, the independent and cumulative fission product yields, and the prompt $γ$-ray energy spectra for the photonuclear reactions on $^{235,238}$U and $^{239}$Pu are calculated with the Hauser-Feshbach Fission Fragment Decay (HF$^3$D) model and compared with available experimental data. In the analysis of neutron-induced fission reactions to the case of photo-induced fission, an excellent reproduction of the delayed neutron yields supports a traditional assumption that the photo-fission might be similar to the neutron-induced fission at the same excitation energies regardless of the spin and parity of the fissioning systems.

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Toshihiko Kawano, Amy E. Lovell, Shin Okumura, Hirokazu Sasaki, Ionel Stetcu, Patrick Talou. 2022-12-17. Consideration of memory of spin and parity in the fissioning compound nucleus by applying the Hauser-Feshbach fission fragment decay model to photonuclear reactions. https://doi.org/10.1103/physrevc.107.044608

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