Initial tests of a 10 MW, 35 GHz phase-locked gyrotron oscillator driven by a pulseline accelerator

Summary Form only given, as follows. A 35-GHz gyroklystron experiment has been designed using a 1-MeV, 100-A, 55-ns electron beam from the VEBA pulseline accelerator. The 10-MW design uses two TE/sub 111/ bunching cavities and a TE/sub 121/ output cavity. A helix gun approach is used to generate an electron beam with a low velocity spread (<5%) at a design pitch ratio of approximately 0.75. The operation of the oscillator is described in detail. The locking signal is provided by a 20-kW K/sub a/-band magnetron and is used to drive a slotted cylindrical TE/sub 111/ bunching cavity with a Q of approximately 200. The experiment has been fabricated and cold tested. In initial experimental operation, free-running oscillation at 35 GHz has been observed at about 5-MW output power. The TE/sub 112/ mode of the bunching cavities has been observed to oscillate early in the pulse, but generally not during the voltage flattop, so that it should not interfere with the phase-locking process.<>