Extraction of 1 GW of rf power from an injection locked relativistic klystron oscillator.

Initial results of extracted power from a moderately modulated intense relativistic electron beam are reported. The modulation circuit is operated as a relativistic klystron oscillator frequency locked to an external oscillator. A 40% modulated electron beam has yielded more than 1 GW of rms power to a vacuum load and also radiated through an antenna. The ratio of the rf power to the intense electron beam power is approximately 20%.