Examining the stability of thermally fissile Th and U isotopes

TL;DR

This study investigates the stability and decay modes of thermally fissile thorium and uranium isotopes using relativistic mean field theory, revealing their potential for energy production and astrophysical significance.

Contribution

It provides a detailed theoretical analysis of neutron-rich Th and U isotopes' stability, decay modes, and density distributions using the RMF approach, highlighting their potential energy applications.

Findings

Neutron-rich isotopes are stable against alpha decay.

Highly unstable against beta decay with lifetimes of tens of seconds.

Clusters inside nuclei are identified from density distributions.

Abstract

The properties of recently predicted thermally fissile Th and U isotopes are studied within the framework of relativistic mean field (RMF) approach using axially deformed basis. We calculated the ground, first intrinsic excited state and matter density for highly neutron-rich thorium and uranium isotopes. The possible modes of decay like $\alpha$-decay and $\beta$-decay are analyzed. We found that the neutron-rich isotopes are stable against $\alpha$-decay, however they are very much unstable against $\beta$-decay. The life time of these nuclei predicted to be tens of second against $\beta$-decay. If these nuclei utilize before their decay time, a lots of energy can be produced within the help of multi-fragmentation fission. Also, these nuclei have a great implication in astrophysical point of view. The total nucleonic densities distribution are calculated, from which the clusters inside the parent nuclei are determined. %Most of the thorium isotopes are $\alpha$ emitters, where as some %of them have short half-lives. In some cases, we found the isomeric states with energy range from 2 to 3 MeV and three minima in the potential energy surface of $^{228-230}$Th and $^{228-234}$U isotopes.