S-band superradiance in corrugated waveguide

An intense relativistic electron beam with energy of 550 keV, current of 3 kA and duration of 12 ns was injected into a periodical slow-wave structure and interacted with backward wave. With trapezoidal energy and current pulse profile, microwave pulses with frequency of 5 GHz, duration of 5 ns and output power of 300 MW was observed. The simulated results suggested that the radiation was caused by superradiance.