Cryogenic Accelerator Design for Compact Very High Energy Electron Therapy

We report on the development of a cryogenic X-band (11.424 GHz) accelerator to provide electron beams for Very High Energy Electron therapy. The distributed coupling linac is designed with a 135° phase advance, capable of producing a 100 MeV/m accelerating gradient in a one-meter structure using only 19 MW when operating at 77 K. This peak power will be achieved through pulse compression of a 5-8 MW few-µs pulse, ensuring compatibility with a commercial power source. We present designs of the cryogenic linac and power distribution system, as well as a room temperature pulse compressor using the HE11 mode in a corrugated cavity. We discuss scaling this compact and economical design into a 16 linac array that can achieve FLASH dose rates (> 40 Gy/s) while eliminating the downtime associated with gantry motion.
Proceedings of the 31st International Linear Accelerator Conference, LINAC2022, Liverpool, UK