Predicted performance of a dc beam driven FEM oscillator designed for fusion applications at 200-250 GHz.

摘要

A Free Electron Laser using a DC beam with depressed collector is being developed at the FOM Institute (Netherlands) for plasma heating which will be capable of producing 1 MW CW output over an adjustable tuning range of 200-250 GHz. The basic design parameters for the electron beam, undulator and waveguide circuit are determined using a 3D non-wiggle averaged waveguide mode particle interaction code including AC space charge effects. Novel features of the design include using a step tapered two section wiggler to achieve both the high gain (10) and the required efficiency ((approximately)5%) as well as a rectangular corrugated HE(sub ll) waveguide circuit to handle the high average power requirements. Results are presented on FEM performance including dependence on beam emittance, percent feedback, and operating frequency.