Jiyuan Zhai ( IHEP ) TTC Meeting, JLAB, 6 Nov 2012 IHEP ILC Cavity R&D Jiyuan Zhai ( IHEP ) TTC Meeting, JLAB, 6 Nov 2012

Outline 9-cell Cavities ILC-type Short Cryomodule Summary low loss large grain w/ & w/o HOM, TESLA-like ILC-type Short Cryomodule cryomodule, input coupler, tuner, helium vessel, magnetic shield Summary 2012/11/6 J. Zhai, JLAB TTC Meeting

Low-Loss Cavities (IHEP-01, IHEP-02) Large Grain Nb from Ningxia IHEP-01 w/o HOM 20 MV/m (CBP+CP) IHEP-02 w/ HOM EBW finished this week dumbbell frequency control to process and test in FNAL CBP (with FNAL recipe)+EP higher Eacc and higher Q0 2012/11/6 J. Zhai, JLAB TTC Meeting

TESLA-like Cavity (IHEP-03) Fine grain 9-cell w/ HOM improve EBW structure simplify dumbbell freq. control better EBW environment Collaborate with KEK drawings, experience process and test in mid 2013 Pressure vessel certification for next cavity, install to STF2 linac?

ILC-type Short Cryomodule Key Technology R&D and demonstration Components fabrication and test ongoing Module assembly in mid 2013 Horizontal test in 2014 (cryogenic plant and MBK) Cavity package Input coupler Tuner LLRF system Cryomodule 2012/11/6 J. Zhai, JLAB TTC Meeting

Cryomodule Fabrication 2012/11/6 J. Zhai, JLAB TTC Meeting

High Power Input Coupler Two STF-type input couplers fabricated in 2011. Vacuum problems due to weak sealing structure. Two modified input couplers in fabrication. High power test in early 2013. thick coating bubbles thin coating sublimes Problems with Copper Coating Cold Window and Inner Conductor Warm Window Doorknob Transfer 2012/11/6 J. Zhai, JLAB TTC Meeting

Helium Vessel & Tuner magnetic shielding cylinder inside, Cavity 30 kg,Tuner 36 kg (not shown) Helium vessel and magnetic shield 23 kg IHEP-02 support support magnetic shielding cylinder inside, end caps shielding outside Stress much below the yield limit Slide jack tuner prototype tested on KEK MHI-04 cavity in 2011. New tuner fabrication finished. Ti Bellow Cryogenic Motor Piezo Tuner Test Stand 2012/11/6 J. Zhai, JLAB TTC Meeting

Remnant magnetic field on cavity wall Magnetic shielding Choose 1J79-1.3 H (Oe) Remnant magnetic field on cavity wall (red: along cavity axis, blue: perpendicular) Material tested at different temperatures. Effect of shielding calculated by Opera-3D Earth magnetic field at Beijing: 500 mG. Cryomodule may enhance the field. Simulation shows if the cavity is set up along East-West direction, the remnant field is below 10 mG; if cavity in North-South, the two end cells will be exposed to high magnetic field. Ignoring the effect of the cryomodule vacuum vessel, cavity Q0 will be ~50 % lower for one cavity case.

Summary ILC-type short module integration in 2013 at IHEP. Large grain low-loss shape cavities for high gradient and high Q0 (CBP+CP, EP). TESLA-like cavity for industrialization (R&D prototype, in- house EBW study, transfer to company) and beam test. 2012/11/6 J. Zhai, JLAB TTC Meeting

We would like to thank KEK, FNAL, JLAB and DESY colleagues for their collaboration and support. Thank you. 在 “幻灯片放映”模式，单击箭头进入 PowerPoint 入门中心。 On behalf of the IHEP ILC SRF Team TESLA Technology Collaboration Meeting, JLAB, 6 Nov 2012