Gyrotron multistage depressed collector based on E×B drift concept using azimuthal electric field. II: Upgraded designs
C. Wu, I. Pagonakis, D. Albert, K. Avramidis, G. Gantenbein, S. Illy, M. Thumm, J. Jelonnek
Physics of Plasmas, 2019, Jan, 26 (1), p. 013108
Multistage Depressed Collectors (MDCs) are nontrivial for high-frequency gyrotrons. A basic conceptual design of an E×B MDC using azimuthal electric fields was proposed in Part I of this series. In the present work, several upgraded design proposals based on the basic one will be elaborated. These proposals will significantly reduce the back-stream of electrons, which was the main drawback of the basic design proposal. Another upgraded design proposal will shrink the length and maximal radius of the MDC to be only a fraction of its full-length version. A conceptual design of the final MDC proposal will be given at the end.