Radiative decay of keV-mass sterile neutrinos in a strongly magnetized plasma

Abstract

The radiative decay of sterile neutrinos with typical masses of 10 keV is investigated in the presence of a strong magnetic field and degenerate plasma. Full account is taken of the strongly modified photon dispersion relation relative to vacuum. The limiting cases of relativistic and non-relativistic plasma are analyzed. The decay rate in a strongly magnetized plasma as a function of the electron number density is compared with the un-magnetized case. We find that a strong magnetic field suppresses the catalyzing influence of the plasma on the decay rate.

Radiative decay of keV-mass sterile neutrino in magnetized electron plasma

“…This process has been considered by several groups in the different cases: vacuum [12], electron plasma [13][14][15][16][17][18], magnetic fields of different configurations [19][20][21][22][23] and magnetized plasma [24][25][26]. The main point of the work we have done [26] was to extend the previous analysis by including the modified photon dispersion relation. The results obtained in [26] are briefly presented in this contribution.…”

“…This relation allows us to express the plasma frequency in terms of the electron number density and magnetic field as follows [26]:…”

“…In addition, we assume that this neutrino is massless and neglect the modification of its dispersion relation by the magnetized plasma. In the strong magnetic field limit, we may transform the axial-vector current of electrons in the Lagrangian (6) to the vector current [26]:…”

“…The neutrino current j α of our interest is responsible for the transition of a sterile neutrino to an active one [26]:…”

“…The main point of the work we have done [26] was to extend the previous analysis by including the modified photon dispersion relation. The results obtained in [26] are briefly presented in this contribution.…”