Models of supernova explosion and the neutrino magnetic moment

The compatibility of the neutrino magnetic moment η ≅ 10-11 μB with the observations of SN 1987 A is discussed. The nonzero neutrino magnetic moment may drastically influence the fate of a supernova, since strong electric and magnetic fields then transform the left-handed neutrinos trapped in the stellar core into the right-handed ones which can almost freely stream out the core. This leakage could be stopped at some circumstances by the resonance transition of the right-handed neutrinos back into the left helicity state in a strong magnetic field inside the star. In the collapse models with high initial entropy and very strong deleptonization of the core this transition takes place above the neutrinosphere - this leads to contradiction with observations for η=10-11 μB. Very cold models with low deleptonization also result in a powerful leakage of right-handed neutrinos. Models of intermediate entropy and core deleptonization, corresponding to the collapse of the mass M ≅ 1.3-1.4 MSun in the standard stellar evolution calculations, may be adequate to the observations for high magnetic moment η ≅ 10-11 μB