Анотація:
The influence of resonant electrons in phase space on the nonlinear dynamics of electron-cyclotron waves is investigated. It is shown that in the case when the frequency of externally applied electromagnetic waves is close to that of the electron-cyclotron waves, the nonlinear coupling between the electron-cyclotron waves and the resulting longitudinal perturbations is mainly caused by the pondermotive potential of the electrons. It is shown that in the competition of refraction caused by the non-resonant electrons and the relativistic nonlinearity, the influence of resonant electrons will increase strongly. The reaction of such longitudinal waves with electrons that are in resonance with high frequency electromagnetic field changes the character of the soliton propagation in an essential manner.