Recent results of research on a 1.3 GHz annular electron beam powered multi-gigawatt microwave amplifier

Summary form only given, as follows. An annular electron beam amplifier has been studied experimentally. This work includes the generation of an annular electron beam (400 kV, 16 kA) using the IMP pulser (500 kV, 5 /spl Omega/, 300 ns), the initial modulation of this beam by a cavity excited with a 500-kW magnetron, and the modulation of the electron beam. The experiments include investigation of the power required for a required modulation of the electron beam, and the resulting modulating voltage impressed on the cavity gap. Comparisons of the experimental results with results of computer simulations from the 2 1/2-D code MAGIC and the 1-D analytic code RKA have been made.