Operation of a megawatt 110 GHz gyrotron with an internal modeconverter

摘要

High frequency gyrotrons suitable for heating fusion plasmas arepresently being investigated at MIT. In tests with a conventionaltapered cavity, powers up to 0.84 MW were obtained in the TE_23,6,1 mode at 113.2 GHz, for an efficiency of 23%. It was found thatthe most severe mode competition was with other azimuthal TE modes. Inlater experiments, a mode converter that produces a Gaussian output rfbeam was added inside the gyrotron. Diode scans of the output beamindicated that a high quality Gaussian beam of the correct dimensionswas produced