Development of cryomodule for ERL main linac

Sakai, Hiroshi*; Umemori, Kensei*; Sato, Masato*; Sawamura, Masaru; Shinoe, Kenji*; Furuya, Takaaki*; Cenni, E.*

We are developing a cryomodule for ERL main linac consisting of 1.3GHz superconducting cavities. Two models of superconducting cavities were fabricated and achieved about 25MV/m. They also satisfied the requirement of 110 of Q0 at 25MV/m of accelerating field. Two cavities for cERL module were fabricated and vertical measurements are in progress. High power test for the input coupler was performed by cooling at liquid nitrogen temperature in the vacuum chamber. The input coupler could feed 25kW after 8-hour process and keep 20kW standing wave for 16 hours, which satisfied the power level for ERL main linac. HOM absorber models were fabricated and sufficiently damped HOM in the cavity. We have adopted slide-jack-type tuners and piezo tuners.