Probing the fission properties of neutron-rich actinides with the astrophysical $r$ process

TL;DR

This paper reviews how fission influences the r-process nucleosynthesis in astrophysical environments, focusing on fission barriers, rates, fragment distributions, and their impact on heavy element formation and observed stellar abundances.

Contribution

It provides a comprehensive analysis of fission's role in the r-process, including recent models and comparison with stellar data, highlighting uncertainties and their effects.

Findings

Fission barriers and rates significantly affect actinide production.

Fission fragment distributions influence the abundance patterns of heavy elements.

Comparison with stellar data suggests fission may contribute to the universality of r-process abundances.

Abstract

We review recent work examining the influence of fission in rapid neutron capture ($r$-process) nucleosynthesis which can take place in astrophysical environments. We briefly discuss the impact of uncertain fission barriers and fission rates on the population of heavy actinide species. We demonstrate the influence of the fission fragment distributions for neutron-rich nuclei and discuss currently available treatments, including recent macroscopic-microscopic calculations. We conclude by comparing our nucleosynthesis results directly with stellar data for metal-poor stars rich in $r$-process elements to consider whether fission plays a role in the so-called `universality' of $r$-process abundances observed from star to star.