Development of a HOM-damped cavity for the KEK B-factory (KEKB)

This paper describes a high-power test model of the normal conducting RF cavity for the KEK B Factory, KEKB. This cavity is loaded with a large coaxial waveguide for higher order mode (HOM) damping. The waveguide is equipped with a notch filter designed to block the TEM wave at the accelerating frequency of 509 MHz. Other waves coupled with the cavity HOMs are guided through the filter and absorbed by bullet-shape sintered SiC ceramics. This prototype model has been designed and built to demonstrate the performance in high power operation and the fabrication technologies involved. The results of the high-power test is reported together with the cavity structure and its RF properties.