Quantum-mechanical description of angular motion of fission fragments at scission

TL;DR

This paper develops a quantum-mechanical model for the angular motion of fission fragments at scission, explaining experimental observations of angular momentum correlations and their dependence on fragment deformation.

Contribution

It introduces a novel quantum-mechanical framework for describing the collective angular motion of touching fission fragments, elucidating spectral features and correlations.

Findings

Angular motion resembles independent vibrations around the pole-to-pole configuration.

The model explains the lack of correlation between fragment angular momenta.

It accounts for the saw-tooth pattern in angular momentum distribution relative to fragment mass.

Abstract

The quantum-mechanical description of the collective angular motion in a system of two touching fission fragments is proposed. The main peculiarities of excitation spectrum and the structure of the wave functions are investigated. As found, the angular motion approximately corresponds to independent vibrations of fragments around the pole-to-pole configuration. The model allows us to explain the experimentally observed lack of correlation between the angular momenta of fission fragments. Additionally the correlation between angular momentum and fragment mass is primarily linked to the change of fragments deformation. The saw-tooth behavior of angular momentum distribution with respect to the fragment mass is well explained.