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arXiv · 2302.03864

Three-dimensional potential energy surface for fission of $^{236}$U within covariant density functional theory

Ming-Hui Zhou·Ze-Yu Li·Sheng-Yuan Chen·Yong-Jing Chen·Zhi-Pan Li
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Abstract

We have calculated the three-dimensional potential energy surface (PES) for the fission of compound nucleus $^{236}$U using the covariant density functional theory with constraints on the axial quadrupole and octupole deformations $(\beta_2, \beta_3)$ as well as the nucleon number in the neck $q_N$. By considering the additonal degree of freedom $q_N$, coexistence of the elongated and compact fission modes is predicted for $0.9\lesssim \beta_3 \lesssim 1.3$. Remarkably, the PES becomes very shallow across a large range of quadrupole and octupole deformations for small $q_N$, and consequently, the scission line in $(\beta_2, \beta_3)$ plane will extend to a shallow band, which leads to a fluctuation for the estimated total kinetic energies by several to ten MeV and for the fragment masses by several to about ten nucleons.

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Ming-Hui Zhou, Ze-Yu Li, Sheng-Yuan Chen, Yong-Jing Chen, Zhi-Pan Li. 2023-02-08. Three-dimensional potential energy surface for fission of $^{236}$U within covariant density functional theory. https://doi.org/10.1088/1674-1137%2Facc4ac

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