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.