From electromagnetic neutrinos to new electromagnetic radiation mechanism in neutrino fluxes

A massive neutrino has nonzero magnetic moment and is involved in the electromagnetic interactions with external fields and photons. The electromagnetic neutrino moving in matter can emit the spin light (SL nu) in the process of transition between two quantum states in matter. In quite resembling way an electron can emit spin light in moving background composed of neutrinos, that is "the spin light of an electron in neutrino flux" (SLe nu). In this paper we obtain the exact solution for the wave function and energy spectrum for an electron moving in a neutrino flux and consider the SLe nu as the transition process between two electron quantum states in the background. The SLe nu radiation rate, power and emitted photon energy are calculated. Notably, the energy spectrum of the emitted SLe nu photons can span up to gamma-rays. We argue that the considered SLe nu can be of interest for astrophysical applications, for supernovae processes in particular.