A NEW MULTI-DIMENSIONAL GENERAL RELATIVISTIC NEUTRINO HYDRODYNAMICS CODE FOR CORE-COLLAPSE SUPERNOVAE. II. RELATIVISTIC EXPLOSION MODELS OF CORE-COLLAPSE SUPERNOVAE

Abstract

We present the first two-dimensional general relativistic (GR) simulations of\nstellar core collapse and explosion with the CoCoNuT hydrodynamics code in\ncombination with the VERTEX solver for energy-dependent, three-flavor neutrino\ntransport, using the extended conformal flatness condition for approximating\nthe spacetime metric and a ray-by-ray-plus ansatz to tackle the\nmulti-dimensionality of the transport. For both of the investigated 11.2 and 15\nsolar mass progenitors we obtain successful, though seemingly marginal,\nneutrino-driven supernova explosions. This outcome and the time evolution of\nthe models basically agree with results previously obtained with the PROMETHEUS\nhydro solver including an approximative treatment of relativistic effects by a\nmodified Newtonian potential. However, GR models exhibit subtle differences in\nthe neutrinospheric conditions compared to Newtonian and pseudo-Newtonian\nsimulations. These differences lead to significantly higher luminosities and\nmean energies of the radiated electron neutrinos and antineutrinos and\ntherefore to larger energy-deposition rates and heating efficiencies in the\ngain layer with favorable consequences for strong non-radial mass motions and\nultimately for an explosion. Moreover, energy transfer to the stellar medium\naround the neutrinospheres through nucleon recoil in scattering reactions of\nheavy-lepton neutrinos also enhances the mentioned effects. Together with\nprevious pseudo-Newtonian models the presented relativistic calculations\nsuggest that the treatment of gravity and energy-exchanging neutrino\ninteractions can make differences of even 50-100% in some quantities and is\nlikely to contribute to a finally successful explosion mechanism on no minor\nlevel than hydrodynamical differences between different dimensions.\n