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arXiv · 2309.07489

EXFOR-based simultaneous evaluation for neutron-induced fission cross section of plutonium-242

Riko Okuyama·Naohiko Otuka·Go Chiba·Osamu Iwamoto
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Abstract

The $^{242}$Pu neutron-induced fission cross section was evaluated from 100 keV to 200 MeV. The experimental $^{242}$Pu and $^{235}$U fission cross sections and their ratios in the EXFOR library were reviewed and analysed by the least-squares method. Additional simultaneous evaluation was performed by including the experimental database of the $^{233,238}$U and $^{239,240,241}$Pu fission cross sections and their ratios developed for JENDL-5 evaluation. The $^{242}$Pu fission cross sections from our evaluation and JENDL-5 evaluation are close to each other below 1 MeV while systematically differ from each other above 10 MeV. The cross section from our evaluation is systematically lower than the JENDL-4.0 cross section in the prompt fission neutron spectrum peak region ($\sim$5% lower around 1 MeV). The newly evaluated $^{242}$Pu fission cross section was verified against the cross section measured in the $^{252}$Cf spontaneous fission neutron field and criticalities of small-sized LANL fast systems, and demonstrated better performance than the JENDL-4.0 cross section on the same level with the JENDL-5 cross section.

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Riko Okuyama, Naohiko Otuka, Go Chiba, Osamu Iwamoto. 2023-09-14. EXFOR-based simultaneous evaluation for neutron-induced fission cross section of plutonium-242. https://doi.org/10.1080/00223131.2023.2267070

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