Photoproduction of neutrinos on nuclei in a strong magnetic field

The photoproduction of a neutrino pair on a nucleus, $\gamma + Ze \to Ze + \gamma + \nu + \bar\nu$, is investigated in a strong magnetic field. It is shown that taking account of the photon dispersion in a strong field reduces appreciably the catalyzing effect of the latter on the process. Therefore, at any field magnitude, neutrino photoproduction cannot compete with the Urca processes. This conclusion contradicts a recent statement in the literature.