Design of a 50 MW, 34 GHz second harmonic coaxial gyroklystron for advanced accelerators

Summary form only given. In this design study, we present the simulated operating characteristics of a four cavity 34 GHz second-harmonic gyroklystron tube which is capable of producing about 60 MW of peak power with an efficiency of about 40% and a gain above 50 dB. The electron gun is a single-anode magnetron injection gun. The input cavity is a TE/sub 011/ cavity which is driven at 17 GHz. The remainder of the cavities are TE/sub 021/ cavities which interact near the second harmonic of the cyclotron frequency. The gain cavity and the output cavities are at twice the drive frequency, but the penultimate cavity is detuned to enhance efficiency. All cavities are abrupt-transition cavities. Both systems are derived from scaled versions of our 17 GHz tube. In this paper, we present detailed designs and performance predictions for both the electron gun and the microwave circuit.