Cherenkov emissions of Langmuir plasmons and light neutrinosby the flux of neutrinos

Abstract

We consider the system of neutrino-antineutrino $\overline v$ – plasma taking into account theirweak Fermi interaction, when the density of neutrinos ν andthe plasma particles are rather high and their collective interactionplays a vital role. New fluid instabilities driven by strong neutrino flux in aplasma are observed. It is shown that a bunch of neutrinos, drifting witha constant velocity across a homogeneous plasma, can also induce emission oflower energy neutrinos due to scattering, i.e. the decay of a heavy neutrinoν_H into a heavy and a light neutrino ν_L(ν_H→ν_Hν_L) in a plasma. Furthermore we find thatthe neutrino production in stars does not lead in general to energy lossesfrom the neutron stars.