THE MICRO-PHYSICS OF NEUTRINO TRANSPORT AT EXTREME DENSITY

Abstract

Production and propagation of neutrinos in hot and dense matter plays an important role in the thermal evolution of neutron stars. In this article we review the micro-physics that influences weak interaction rates in dense matter containing nucleons, leptons and or quarks. We show that these rates depend sensitively on the strong and electromagnetic correlations between baryons. We present new results, obtained using molecular dynamics, for the response of dense plasma of heavy ions. Neutrino rates are also shown to be sensitive to the phase structure of matter at extreme density. We highlight recent calculations of neutrino rates in dense color superconducting phases of quark matter. We present a brief discussion of how these differences may affect the early evolution of a neutron star. Neutrinos play an important role in stellar evolution. By virtue of their weak interactions with matter neutrinos provide a mechanism for energy loss from the dense stellar interiors. In neutron stars, neutrino emission is the dominant cooling mechanism from the their birth in a supernova explosion until several thousand years of subsequent evolution. In this talk, we present an overview of some of the nuclear/particle physics issues that play a role in understanding the rate ofmore » propagation and production of neutrinos inside neutron stars. The calculation of these rates are of current interest since several research groups are embarking on large scale numerical simulations of supernova and neutron star evolution. Even moderate changes in the nuclear microphysics associated with the weak interaction rates at high density can impact macroscopic features that are observable.« less