How the Fission of Heavy Elements Impacts Nuclear Abundances Produced by Kilonovae

Neutron star mergers (NSMs) are one of the few places in the universe that provide the necessary conditions to support r-process nucleosynthesis, the mechanism by which the heaviest nuclides in our universe are created. This highly dynamic process heavily relies on the competition between β-decay and rapid neutron capture to create new elements but the behavior of heavier, more exotic nuclei also shapes the final nuclear abundances produced by these cataclysmic events. By varying the competition between dominating decay channels of heavy and superheavy nuclides as input to PRISM, a nucleosynthesis reaction network, the fission behavior of heavy and superheavy nuclides was shown to play a role in the enhancement of lanthanide product in a mass asymmetric NSM. These results give insight into how the fission recycling of material in the dynamical ejecta of a NSM may shape the evolution of transient signals.