DEVELOPMENT OF C-BAND ACCELERATING SECTION FOR SUPERKEKB

In a future luminosity upgrade from the present KEK-B factory to the SuperKEKB, the injector linac is required to increase the positron acceleration energy from 3.5 GeV to 8.0 GeV. It could be realized by replacing some of the present S-band accelerator modules to the C-band mod-ule and doubling the acceleration field gradient (21 → 42 MV/m). Research and development of the components for the C-band module has been performed since 2002. This paper reports on the development of the first prototype of the C-band accelerating section whose design is based on a half-scale dimension of the present S-band 2-m long sec-tion. Details in the design and the fabrication are described. Results of the high-power test, beam acceleration test and ten months ’ operation in the KEKB injector linac are given