Constraints on the Progenitor of Cassiopeia A

We compare a suite of three-dimensional explosion calculations and stellar models incorporating advanced physics with observational constraints on the progenitor of Cassiopeia A. We consider binary and single stars from 16 to 40 M_solar with a range of explosion energies and geometries. The parameter space allowed by observations of nitrogen-rich high-velocity ejecta, ejecta mass, compact remnant mass, and ⁴⁴Ti and ⁵⁶Ni abundances individually and as an ensemble is considered. A progenitor of 15-25 M_solar that loses its hydrogen envelope to a binary interaction and undergoes an energetic explosion can match all the observational constraints.