Whistler waves emission by a modulated electron beam: Nonlinear theory

The nonlinear theory for the interaction of a thin modulated electron beam with a monochromatic whistler wave is considered. On the basis of wave field structures calculated previously in the linear approach, equations describing the wave amplitude evolution inside and outside the beam are obtained. These equations, together with the equations for particle motion in the drift approximation, form the self-consistent nonlinear model. Double and single pole resonance cases are considered. The full system of equations (taking into account the finite size of the beam) is resolved by a computer code which yields clear physical results. This code avoids the heavy structure and the long computer time inherent in the usual Particle-In-Cell simulation codes.