NEUTRINO PAIR SYNCHROTRON-RADIATION FROM RELATIVISTIC ELECTRONS IN STRONG MAGNETIC-FIELDS

The emissivity for the neutrino pair synchrotron radiation in strong m agnetic fields has been calculated both analytically and numerically f or high densities and moderate temperatures, as can be found in neutro n stars. Under these conditions, the electrons are relativistic and de generate. We give here our results in terms of a universal function of a single variable. For two different regimes of the electron gas we p resent a simplified calculation and compare our results to those of Ka minker et al. Agreement is found for the classical region, where many Landau levels contribute to the emissivity, but some differences arise in the quantum regime. One finds that the emissivity for neutrino pai r synchrotron radiation is competitive with and can dominate, other ne utrino processes for magnetic fields of the order B similar to 10(14)- 10(15) G. This indicates the relevance of this process for some astrop hysical scenarios, such as neutron stars and supernovae.