Radiation and self-polarization of neutral fermions in quasi-classical description

A Lorentz invariant formalism for quasi-classical description of electromagnetic radiation from a neutral spin 1/2 particle with an anomalous magnetic moment moving in an external electromagnetic field is developed. In the high symmetry fields, for which analytical solutions to the Bargmann--Michel--Telegdi equation are known, the so called self-polarization axes, i. e. directions of preferred polarization of particles in the radiation process, are found. Expressions for the radiative transition probability and spectral-angular distribution of the radiation emitted by a polarized particle are obtained in the fields under consideration.