Neutrino Pair Emission by a Stellar Plasma

Various current models and generalizations of a universal weak Fermi interaction predict a first-order weak coupling between electrons and $\nu -\overline{\nu }$ pairs. The radiation of such pairs by a hot, partially degenerate relativistic plasma is calculated for temperatures and densities that appear to be relevant for stellar evolution. Neutrino-pair emission by collective electron modes, especially transverse plasma excitations, is found to be the main mechanism for neutrino radiation by a dense stellar plasma when electron-positron production is small either because the temperature is too low ($T\lesssim {10}^8$ °K) or degeneracy supresses it. The neutrino luminosity of a star can greatly exceed its photon luminosity for a central core temperature greater than ${10}^8$ °K.