High-harmonic gyrotron with sectioned cavity

High-harmonic large-orbit gyrotrons require long-length operating cavities because of both a weak electron-wave coupling and relativeily low electron currents. Since diffraction Q-factors of such cavities are very high, a great share of radiated rf power is spent to Ohmic losses. In this letter, a sectioned klystronlike cavity is proposed as a way to combine a long electron-wave interaction region with a relatively low diffraction Q-factor. In addition, the use of such a cavity makes a relatively broadband frequency tuning possible.