The supernova shock .6.

The supernova shock originates from the convective region and breaks out at about 300 km. The driving force is the recombination of nucleons into alpha-particles. The net energy per gram available for the shock is estimated. Matter accumulates in the convective region by accretion; the density of this matter can be calculated from the density and velocity of the matter falling in from the outside. From these arguments the energy given originally to the shock is estimated to be about 1 foe, in rough agreement with observation. It is speculated that this energy does not depend much on the mass of the progenitor.