Development and Integration Testing of a Power Coupler for a 3.9-GHz Superconducting Multicell Cavity Resonator

A coaxial power coupler for a superconducting multicell cavity resonator at 3.9 GHz has been developed. The cavity is intended to be employed as an accelerator to provide enhanced electron beam quality in a free-electron laser. Due to cryogenic high-vacuum and high-power requirements, special provisions for two windows and two bellows were implemented. A simulation tool was employed to optimize th...