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arXiv · 1609.01424

Microscopic phase-space exploration modeling of $^{258}$Fm spontaneous fission

Yusuke Tanimura·Denis Lacroix·Sakir Ayik
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Abstract

We show that the total kinetic energy (TKE) of nuclei after the spontaneous fission of $^{258}$Fm can be well reproduced using simple assumptions on the quantum collective phase-space explored by the nucleus after passing the fission barrier. Assuming energy conservation and phase-space exploration according to the stochastic mean-field approach, a set of initial densities is generated. Each density is then evolved in time using the nuclear time-dependent density-functional theory. This approach goes beyond mean-field by allowing spontaneous symmetry breaking as well as a wider dynamical phase-space exploration leading to larger fluctuations in collective space. The total kinetic energy and mass distributions are calculated. New information on the fission process: fluctuations in scission time, strong correlation between TKE and collective deformation of daughter nuclei as well as pre- and post-scission particle emission, are obtained.

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Yusuke Tanimura, Denis Lacroix, Sakir Ayik. 2017-03-21. Microscopic phase-space exploration modeling of $^{258}$Fm spontaneous fission. https://doi.org/10.1103/physrevlett.118.152501

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