A megawatt-class 220 GHz conventional cavity gyrotron

In this paper, a first preliminary design study of a 220 GHz, 1 MW gyrotron cavity is presented for probable continuous wave applications in space power grids and electron cyclotron heating and current drive (ECH&CD) in future magnetically confined thermonuclear fusion plasmas. The present work includes a careful selection of the candidate modes followed by studies on mode competition, cold cavity design and initial RF-behavior computations.