Quasilinear theory of cyclotron heating of plasma in toroidal systems by monochromatic radiation

Averaged equations are obtained for electron motion under cyclotron resonance conditions in the electromagnetic field of the ordinary wave of finite amplitude for the case of quasi-transverse propagation. The characteristic time intervals are pointed out, for which the wave-electron interaction is essentially different in the initial problem. The conditions are given under which this interaction is determined by the linear theory. Taking into account the rotational transform in toroidal systems, a quasilinear equation for the evolution of the electron distribution function is obtained, which is equivalent to that describing a heating in the h.f. field with a noise spectrum. The optical plasma depth for an ordinary wave is shown to remain constant during the course of quasilinear relaxation.