Stimulated electromagnetic interactions in spatiotemporally gyrating relativistic electron beams

Summary form only given, as follows. One possible method to significantly widen the bandwidths of present gyroklystron amplifiers is to utilize extended interaction structures in the input sections, the buncher sections and the output sections, in conjunction with stagger tuning. Through extended interactions, however, electron beams can undergo stimulated electromagnetic interactions, causing multimode excitations. In this paper, we investigate stimulated electromagnetic interactions in relativistic electron beams gyrating in an externally applied uniform magnetic field. The electron gyrophases are assumed to have strong spatiotemporal correlations. By applying Vlasov-Maxwell equations together with Lorentz transformations, we obtain the general dispersion relation for electromagnetic and electrostatic wave perturbations on the electron beam for this system. The dispersion relation is used to analyze a variety of stimulated electromagnetic interactions on such electron beams. Results of these analyses are discussed.