HIGH-EFFICIENCY CAVITY DESIGN OF A 170 GHZ GYROTRON FOR FUSION APPLICATIONS

The design of high power, continuous wave (cw), 170 GHz gyrotron cavit ies is considered. The anticipated degradation of efficiency with beam velocity spread places a premium on the optimization of efficiency. F or parameters of interest achievement of high efficiency requires util ization of a high quality cavity. Two options are considered: a barrel cavity and a long simple tapered cavity operating at low voltage. The cavities are examined for their sensitivity to velocity spread, their mode competition, and their maximum Ohmic power dissipation. (C) 1997 American Institute of Physics.