Neutrino Transport in Core Collapse Supernovae

Abstract

Neutrino production, transport, and interaction is arguably the single-most important component of a core collapse supernova model. Neutrinos are believed to be responsible for powering these supernovae, in part or entirely, and their production and transport set the stage for the radiation magnetohydrodynamics of stellar core collapse and bounce, which provides the initial conditions for the post-stellar-core-bounce dynamics. Neutrino transport is governed by multidimensional, phase-space, integro-partial differential kinetic equations. The solution of these equations dominates the computational challenge in simulating this supernova class. We present the neutrino transport and neutrino radiation hydrodynamics equations involved, and their finite differencing, and briefly discuss their solution. We use the spherically symmetric (spatially one-dimensional) case to illustrate the equations and the issues involved, but give the general formalism for the spatially multidimensional case as well. We conclude by briefly discussing the implications of the now experimentally measured nonzero neutrino masses.