Previous calculations of the emissivity of a plasma due to the decay of transverse photons and plasmons into neutrino pairs have used dispersion relations that are inaccurate at relativistic temperatures or densities. In the high-temperature limit, the use of the current ultrarelativistic dispersion relations increases the emissivity by a factor of 3.185. This may have a significant effect on the initial cooling rate for the core of a neutron star.

• Received 26 December 1990

DOI:https://doi.org/10.1103/PhysRevLett.66.1655