Mechanical feedback from black hole accretion as an energy source of core-collapse supernova explosions

According to the traditional scenario for core-collapse supernovae, the core of the collapsing star forms a neutron star (NS) and its gravitational energy release sends out a shock wave into the stellar envelope. However, in a significant number of numerical simulations, the shock stalls and the star cannot be exploded successfully, especially for a massive, compact star. We consider an alternative scenario in which, with mass fallback, the collapsing star forms a black hole in the center, surrounded by a dense, hot accretion disk, which blows out an intense outflow (wind). The kinetic energy of the wind may result in a successful stellar explosion. With an improved version of the formalism in Kohri et al., who studied NS accretion of minor fallback, we study this disk wind-driven explosion by calculating the accretion history for a suite of pre-SN stellar models with different initial surface rotational velocities, masses and metallicities, and by comparing the disk wind energy with the binding energy of the infalling stellar envelope. We show that the most promising models to be exploded successfully by this new channel are those relatively compact pre-SN stars with relatively low metallicities and not too low specific angular momenta. The total energies of the explosions are similar to 10(51-52) erg, and a more massive progenitor may produce a more energetic explosion.