Contribution of the crust to the neutrino luminosoity of neutron stars

The contributions of various processes to the radiation of neutrino pairs by the crust of neutron stars have been reexamined in the Weinberg-Salam model of the weak interaction and using the results of Hartree-Fock calculations to describe the nuclei present in the crust at densities higher than the neutron drip point. The importance of the neutral current contribution to the resulting emissivities is discussed as a function of the Weinberg angle and of the possible number of massless neutrinos. A comparison with recent calculations of the neutrino luminosity of the interior of neutron stars shows the relative importance of the neutrino luminosities from the crust and from the inner part of the star in the absence of pion condensates. For this comparison, three different equations of state have been used and the effect of the density dependence of the nucleon effective mass and of the superfluid proton and neutron transitions on the role of the crust cooling is discussed. (Auth.)