Institute for Advanced Study Informal Astrophysics Seminar

The explosion of massive stars involves the formation of a shock wave. In stars that form iron cores, this shock wave stalls on its way out due to the breakup of heavy nuclei and neutrino emission. In the currently most favored explosion scenario, a fraction of the gravitational binding energy of the collapsed core radiated in neutrinos needs to be absorbed by the material below the shock. The required energy depends on the interplay between non-spherical hydrodynamic instabilities, neutrino heating, and nuclear dissociation. I will report results of one- and two-dimensional hydrodynamic simulations that model key physical components of the system and separate them out to examine their combined effects. In particular, I'll focus on the effects of nuclear dissociation on non-spherical shock oscillation modes, and on the interplay between neutrino heating and alpha particle recombination in the dynamics and critical heating rate for explosion.