Extending Core-Collapse Supernova Simulations: from the Onset of Explosion to Shock Breakout

As well as contributing to star formation, core-collapse supernovae (CCSNe) are the richest astrophysical producers of heavy elements. As the explosion progresses, the evolution of the nuclear species synthesized in the early-time of the explosion is strongly coupled with the hydrodynamics. Hydrodynamic instabilities, specifically Rayleigh-Taylor instabilities, affect the distribution of material most strongly. Our aim is to understand how the instabilities in the central engine drive inhomogeneities in the ejecta, leading to the observed elemental distribution. To achieve this understanding, and to accurately replicate the observed asymmetries, multi-dimensional simulations of the supernova explosion must be carried beyond the initial seconds where the central engine operates and the nucleosynthesis occurs. We have therefore performed simulations with the FLASH code that follow the progression of the explosion throughout the entire star, starting from neutrino-radiation hydrodynamic simulations of the first seconds performed with the CHIMERA code. At present, we have performed two-dimensional and three-dimensional FLASH simulations starting from two-dimensional CHIMERA models of a 9.6 M⊙ zero-metallicity progenitor, and a 10 M⊙ solar metallicity progenitor, all simulated until shock-breakout while tracking the 160 nuclear species evolved in the CHIMERA models. We are presently exploring differences that result when three-dimensional CHIMERA models are used as the initial conditions.