LINEAR-ANALYSIS OF PERIODIC-WAVE-GUIDE CYCLOTRON MASER INTERACTION

Following recent experimental studies, we present in this paper a line ar model of the periodic-waveguide cyclotron maser. This device is bas ed on a cyclotron-type interaction of a nonrelativistic electron beam with traveling waves in a metallic periodic waveguide. The kinetic mod el presented in this paper incorporates the periodic-waveguide spatial wave harmonics with the cyclotron and Weibel interactions. It results in a Pierce-type gain-dispersion equation with new coupling terms. Th e dependence of the cyclotron amplification on the low impedance of th e inductive periodic waveguide and on the electron initial transverse velocity is analyzed in various operating regimes. In agreement with e xperimental results, this analysis shows that amplification is feasibl e in certain conditions without an initial electron transverse velocit y (V0perpendicular-to = 0) and with a wide acceptance of electron beam energy variation.