Quasilinear analysis of loss-cone driven weakly relativistic electron cyclotron maser instability

Abstract

This paper presents a quasilinear analysis of the relativistic electron cyclotron maser instability. Two electron popUlations are assumed: a low-temperature background component and a more energetic loss-cone population. The dispersion relation is valid for any ratio of the energetic to cold populations, and includes thermal and relativistic effects. The quasilinear analysis is based upon·an efficient kinetic moment method, in which various moment equations are derived from the particle kinetic equation. A model time-dependent loss-cone electron distributidn function is assumed, which allows one to evaluate the instantaneous linear growth rate as well as the moment kinetic equations. These moment equations along with the wave kinetic equation form a fully self-consistent set of equations which governs the evolution of the particles as well as unstable waves.' This set of equations is solved with physical parameters typical of the earth's auroral zone plasma. © 1995 American Institute of Physics