Neutrino magnetic moment and neutron star cooling

The effects of a finite neutrino magnetic dipole moment on the cooling of neutron stars are studied. It is shown that a finite magnetic moment ([mu][sub [nu]]) of the order of 10[sup [minus]10] in units of the Bohr magneton ([mu][sub [ital B]]) would modify the standard cooling curve of neutron stars for a period of 10--10[sup 3] yr after their birth, which demonstrates how crust cooling could compete with core cooling within the typical time scale for thermal conduction from the core to the surface. The consistency with the current observational data gives a limit [mu][sub [nu]][lt]5[times]10[sup [minus]7][mu][sub [ital B]] and possible improvements of this value in the future are discussed.