How being single or in a couple affects the death of massive stars
Most massive stars live in binary systems and will interact during their lifetime. As a result, they may lose or gain mass and end their lives with structures and compositions that differ significantly from stars that do not interact with a companion. However, most calculations of the final structure of massive stars at the moment of core-collapse rely on single-star models. We present the first systematic study employing full binary evolution models to investigate the difference between the structure of single stars and stars of the same initial mass that have been stripped in a binary system after leaving the main sequence. We employ the MESA stellar evolution code to compute two grids of 20 stellar models between 10 and 20 solar masses with a nuclear network comprising 128 isotopes. We discuss the systematic difference in structure and composition between the stripped and single star models and where they originate. We further investigate the explodability of these stars from multi-dimensional supernova simulations and discuss the implications for supernovae, supernova remnants, and neutron stars.