Conservation of Isospin in Neutron-Rich Fission Fragments

TL;DR

This paper demonstrates that isospin conservation explains the observed mass distribution of fission fragments in neutron-rich nuclei, providing a simple yet powerful insight into fission processes and their broader implications.

Contribution

It shows that isospin conservation accounts for the trends in fission fragment yields across different reactions, highlighting its importance in nuclear fission analysis.

Findings

Isospin conservation explains the relative yields of fission fragments.

Large isospin values significantly influence fission outcomes.

The results suggest improved predictions for fission fragment distributions.

Abstract

On the occasion of the $75^{th}$ anniversary of the fission phenomenon, we present a surprisingly simple result which highlights the important role of isospin and its conservation in neutron rich fission fragments. We have analysed the fission fragment mass distribution from two recent heavy-ion reactions $^{238}$U($^{18}$O,f) and $^{208}$Pb($^{18}$O,f) as well as a thermal neutron fission reaction $^{245}$Cm(n$^{th}$,f). We find that the conservation of the total isospin explains the overall trend in the observed relative yields of fragment masses in each fission pair partition. The isospin values involved are very large making the effect dramatic. The findings open the way for more precise calculations of fission fragment distributions in heavy nuclei and may have far reaching consequences for the drip line nuclei, HI fusion reactions, and calculation of decay heat in the fission phenomenon.