Abstract
The rate at which the energy of a blackbody radiation is converted into neutrinos by the pair annihilation process e+e+ν+ν¯ has been calculated. At T6×109°K the relaxation time for such conversion process is around 100 sec for pure radiation. Since neutrinos have a very long mean free path (≫stellar dimensions) they will escape, thus carrying away the energy. This process therefore will be of astrophysical importance. The rate of energy loss dUdt is tabulated, as a function of temperature and density, together with the chemical potential, the pressure, and the electron-positron energy. This table should be useful for numerical integrations of stellar structure equations in the temperature range (0.5-10)×109 °K, and the density range 0-109 g/cm3.