The Stability of a Magnetized Electron Plasma in the Field of a Circularly Polarized Electromagnetic Wave

The dispersion relation is derived and analyzed for a magnetized electron plasma in the field of a powerful circularly polarized homogeneous pump wave propagating along the constant magnetic field. It is shown that decay instabilities appear for a weak pump while a strong pump, in which the electrons reach ultrarelativistic velocities, leads to aperiodic instabilities.