Neutrino radiative decay in external field and medium
A review of the current status of the theory of massive neutrino radiative decay is presented. We develop our previous studies and perform the detailed analysis of the process of radiative decay of a massive Dirac neutrino in an intense external magnetic field in the presence of medium. The probability of the mentioned above process is calculated. It is found out that the presence of a dense medium essentially increases the rate of decay as compared to the rate of decay in magnetic field. Possible astrophysical applications of the obtained results are considered.