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

TL;DR

This paper models the total kinetic energy in $^{258}$Fm spontaneous fission using a phase-space approach combined with time-dependent density-functional theory, revealing detailed fluctuation and correlation insights.

Contribution

It introduces a novel phase-space exploration method integrated with density-functional theory to better understand fission dynamics and energy distribution.

Findings

Reproduces TKE distribution accurately

Identifies fluctuations in scission time

Discovers correlations between TKE and deformation

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.