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arXiv · 2307.00220

Solving one-dimensional penetration problem for fission channel in the statistical Hauser-Feshbach theory

Toshihiko Kawano·Patrick Talou·Stephane Hilaire
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Abstract

We solve the Schr\"{o}dinger equation for an arbitrary one-dimensional potential energy to calculate the transmission coefficient in the fission channel of compound nucleus reactions. We incorporate the calculated transmission coefficients into the statistical Hauser-Feshbach model calculation for neutron-induced reactions on $^{235,238}$U and $^{239}$Pu. The one-dimensional model reproduces the evaluated fission cross section data reasonably well considering the limited number of model parameters involved. A resonance-like structure appears in the transmission coefficient for a double-humped fission barrier shape that includes an intermediate well, which is understood to be a quantum mechanical effect in the fission channel. The calculated fission cross sections for the neutron-induced reactions on $^{235,238}$U and $^{239}$Pu all exhibit a similar structure.

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Toshihiko Kawano, Patrick Talou, Stephane Hilaire. 2023-07-01. Solving one-dimensional penetration problem for fission channel in the statistical Hauser-Feshbach theory. https://arxiv.org/abs/2307.00220

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