The structure of supernova shock waves

Abstract

The structure of strong shock waves is calculated over the range of shock energies and initial number densities believed to be characteristic of shocks traversing the extended outer envelopes of stars undergoing Type II supernova explosions. The motivation for these calculations is the proposal that the ions in such shocks could be heated to temperatures above 10 MeV by hard ion-ion collisions, resulting in helium spallation and the subsequent formation of enough deuterium through neutron capture to account for the observed deuterium abundance without postulating its formation in a low-density big bang. The analysis takes into account effects of radiative transfer on the energy and momentum balance in a shock as well as relativistic contributions to radiative emission rates from nondipole electron-ion bremsstrahlung, electron-electron bremsstrahlung, and radiative Compton scattering. Several models of strong-shock structure are examined, including a shock model dominated by radiation pressure and transfer plus a number of viscous shock models with and without specific radiation fields. It is concluded that a cosmologically significant amount of deuterium is unlikely to be produced in supernova shock waves.