Competition of Oscillations at Different High Cyclotron Harmonics in the sub-THz Large-Orbit Gyrotron

Recently, 30 keV/0.7A CW sub-THz large-orbit gyrotron have been experimentally realized. Two different modes at different (second and third) cyclotron harmonic were excited in the same cavity separately at slightly different magnetic fields. This work is dedicated to description of various regimes of competition of the two modes observed in the experiment.