EXCITATION OF TM MODE BY A RELATIVISTIC ELECTRON BEAM IN AN AZIMUTHALLY CORRUGATED WAVEGUIDE

The excitation of an electromagnetic TM mode by a relativistic electron beam in a waveguide with a sinusoidalcorrugated azimuth conducting wall in a constant uniform external guiding magnetic field is theoretically studied. We consider a thin annular electron beam moving along the waveguide axis and rotating at an equilibrium radius around its axis. In the approximation of a small corrugation depth, the analytical dependences of the growth rate of instability and resonant frequencies on the parameters of the beam and waveguide are determined.