Development of high power high efficiency S-band PPM klystrons

Calabazas Creek Research is developing several high power S-band periodic permanent magnet (PPM) focused klystrons. We report on the design of a 5.5 MW pulsed klystron and a 75 MW pulsed klystron, both for providing high peak power for advanced accelerators. The efficiency requirement of both klystrons is determined by system requirements. We will present results from extensive simulations using out in-house large signal klystron code (KLSC) and the large signal code TESLA. We will also describe our unique PPM structures which permits direct access to frequency tuning and liquid cooling of the individual cavities.