A free-electron maser (FEM) experiment is currently underway at MIT, in collaboration with TTE (Thomson Tubes Electroniques). The specific purpose of the series of experiments described here is to demonstrate control of the axial mode structure of a high power FEM oscillator. In this paper, we discuss two different approach to this problem; namely, the incorporation of a cavity designed to provide mode-selectivity, and the priming of the oscillator using a 40 kW, 35 GHz magnetron.
T. S. Chu, T. S. Chu,
"A high power free-electron maser oscillator", Proc. SPIE 1514, 15th International Conference on Infrared and Millimeter Waves, 151469 (1 December 1990); doi: 10.1117/12.2301635; https://doi.org/10.1117/12.2301635