R-process nucleosynthesis in numerical simulations: neutron star mergers, collapsars, and other supernovae

The astrophysical origin of heavy r-process elements remains an important open question in nuclear astrophysics today. In recent years, we have obtained a growing number of elemental abundance measurements of metal-poor stars, constraining the potential sites of r-process nucleosynthesis. At the same time, simulations of neutron star mergers, collapsars, and other rare supernovae events proposed as sites of the r-process have greatly improved their prediction for the properties of the matter that they eject. In this presentation, I will review recent results in the simulation of these events, the remaining sources of uncertainties in the determination of their r-process yields, and the challenges that each of these candidates face in matching existing observational data.