Drift theory of the resonant interaction of charged particles with wave packets

Averaged equations of motion are obtained for charged particles resonantly interacting with high-frequency wave packets in the case of finite cyclotron radius. It is shown that the mean action of the packet on the particle is not a potential function. Cherenkov resonance of particles with the beats of two wave packets in inhomogeneous plasma is considered. © 1982 Plenum Publishing Corporation.