It Takes Two: nucleosynthesis in core-collapse supernova simulations of binary-star progenitors

Abstract

Binary interaction is common amongst massive stars and can significantly alter their pre-supernova structure and composition. This has important consequences for the nucleosynthetic yields and observable properties of the resulting supernovae. However, binary-evolved progenitors remain largely unexplored in modern neutrino-driven core-collapse supernova simulations. In this work, we present one- and two-dimensional core-collapse supernova simulations of single- and binary-star progenitors. We investigate the impact of binary interaction on the explosion and examine the effect of in-situ networks on the dynamics and resulting nucleosynthesis relative to post-processing approaches. Our progenitors highlight the impact of binary interaction on the pre-supernova core structure of the star and its significance for explodability. We find that binary progenitors are predicted to be generally more explodable than single stars with the same initial mass, indicating that the supernova outcome cannot be well correlated with the initial mass. However, a systematic comparison of the explosion outcomes of binary- and single-star progenitors from self-consistent simulations is still required to confirm this trend. Energy generation from nuclear reactions, as well as the abundances of key isotopes such as ${}^{56}$Ni, can be well approximated by a small $α$-chain network. However, there are notable discrepancies in the production of Ti, Cr, and Fe isotopes which remain sensitive to the network size and thermodynamic history.