Bremsstrahlung from Neutrino Scattering via Magnetic Dipole Moments

In this paper we discuss bremsstrahlung induced by neutrino scattering. This process should exist since neutrinos are expected to couple to photons via magnetic dipole and transition moments. These moments are loop-induced and tiny in the Standard Model with neutrino masses but could be significantly enhanced in extended theories. As concrete example we study the scattering of the two largest neutrino fluxes on earth, solar neutrinos and Cosmic Neutrino Background (CNB). It is tempting to consider this as a potential signature for CNB searches but it turns out that the signal is extremely small and unlikely to be observed.