STF-2 Cryomodule Performance and New Input Coupler R&D; for ILC

The high power test for STF -2 cryomodule with twelve cavities has completed successfully in 2015. It became clear the average accelerating gradient was 30.3 MV/m, eight cavities achi eved above 31.5 MV/m as the ILC specification, and three cavities had the significant performance degradation by heavy field emission due to the additional clean room work in t he STF tunnel. As the following next steps, there are the LFD (Lorenz Force Detuning) measurem ent, LFD compensation by piezo, and long ru n for check of stable operation at high gradient. In th e long run around 32 MV/m, each cavity without degradation showed the stable operation with the successful LFD compensation by piezo and RF feedback system. On the other hand, from the view point of pl ug-compatibility for the input coupler in the ILC, new STF input couplers with 40mm of input port were re -designed, fabricated and high -power -tested successfully. Moreover, for the lower cost study, another input couplers with coating -free ceramic will be also tested soon in the collaboration of CERN and KEK. In this presentation, the detailed results for STF -2 Cryomodule t est and 40mm input couplers are reported.