Neutrino emission from neutron star crusts

Abstract

Neutrino production is the dominant cooling process in neutron stars. After the rapid cooling during the protoneutron star stage, the neutron star crust is formed. Neutrinos continue to be produced in the crust, which can escape from the surface. This neutrino production is an important process to the final cooling phase of the star. They are produced in the crystalline lattice formed by nuclei permeated by an electronic gas. Quantum oscillations of the electron density with respect to the lattice of nuclei generates plasmons, which decay in a pair of neutrinos. Many works have studied the plasma of the nucleus in the star, however, without incorporating the effect of the lattice in the crust of the neutron star. The objective of this work is to include the lattice in the calculation of the plasmon decay rate using quantum field theory at finite temperature. It is not common to find studies on the crystalline lattice of the star using quantum field theory and the calculations generally used for neutrino emissivity consider a homogeneous and isotropic medium, which can not be directly applied in the context of neutron star crust.