Dynamics and gravitational wave signature of axisymmetric rotational core collapse

Abstract

. We have carried out a comprehensive parameter study of the dynamics of rotational core collapse in massive stars. The iron cores have been approximated by axisymmetric rotating \\Gamma = 4=3 polytropes in rotational equilibrium. Any transport effects by neutrinos have been neglected. We have computed18 initial models which differ by their amount of rotational energy and their distribution of angular momentum. The initial models range from slowly to rapidly rotating and from rigidly to extremely differentially rotating configurations. The collapse was induced by suddenly reducing the adiabatic index \\Gamma to a value \\Gamma r with 1:28 \\Gamma r 1:325. The stiffening of the equation of state at nuclear matter density and the thermal pressure in the matter heated by the prompt shock was simulated by means of a simplified analytic equation of state consisting of a polytropic and a thermal part. The evolution of a total of 78 models was followed well beyond core bounce using a two dimens...