ILC R&D at KEK Beam Control Technology –ATF –ATF2 Acceleration Technology –High-gradient Cavities L-band R&D Stand –Linac System  STF –Construction of Infrastructure STF Building ATF bldg

ATF Accelerator Test Facility Construction started in 1993 Originally as Damping Ring for warm collider Achieved world smallest emittance ~2pm Still usefull for ILC (the only ring that can provide required emittance) World-wide collaboration going-on

ATF Collaboration consult CB (Collaboration Board) Spokesperson (+ 3 deputies) TB (Technical Board) KEK Directorate Coordinators Work Groups assist report appoint nominate assist consult coordinate 1993 construction started as Damping Ring for warm collider World smallest emittance achieved Internationalization GLC  ILC MoU with ~20 institutes Experiment program selected by TB (technical board) TB mtg every May and Dec. SLAC, LBNL, FNAL, Cornell U, CERN, DESY, Orsay, INFN, several univs in London, IHEP, PAL, Japanese univs (Waseda, Nagoya, Tokyo, Hiroshima, etc)

ATF R&D Items Beam tuning for low emittance Beam dynamics studies (fast-ion, wiggler, etc) Fast kicker development for ILC DR (next page) High resolution ring BPM Cavity BPM developments (ATF2, IP-BPM, ATF extraction line, etc) Laser wire Other beam diagnostics devices (XSR, ODR, etc) S-band RF gun CSR (coherent synchrotron radiation.) Laser-Compton based polarized positron production etc. Consistency test from 3 cavity BPMs  resolution ~17nm Pulsed Laser Wire Polarized positron production Beam image from XSR (  y =6.4  m) 3-bunch extraction

Development of Fast Kicker (highlight of 2005) ILC requires fast kickers with rise (fall) time of a few nsec (Otherwise Damping Ring would be too large) Demonstrated in 2005 that ~3ns is feasible (excited an oscillation of stored beam) Try extraction from ATF in 2006 by series of kickers Extraction scheme from DR in ILC Measured kick angle

ATF2 Extend ATF extraction line  Add Final Focus –Small beam size （～ 35nm ） Focus the ATF beam to ~35nm by ILC final focus optics long-term maintenance –Beam center Stabilization of the beam center to ~2nm Bunch-to-bunch feedback system by ILC-like beam Construction start 2005, Operation start Jan.2008 Construction by international collaboration –Asia: fabrication of quads and BPM, etc –Americas: design, BPM electronics, magnet mover, power supply, etc –Europe: feedback, laser wire, final quad support, etc Q-BPM from PAL Qmagnet from IHEP

Development of High Gradient Cavities Baseline: TESLA-type Gradient limited by surface magnetic field (max. ~40MV/m, operation 35MV/m) LL (Low Loss)-type under R&D –Reached 51MV/m with single- cell cavities ~ < 9-cell cavities under study ~29MV/m yet to be installed in STF Phase 1

Infra-structure for SC-RF production Cryogenic compressor Cryogenic liquefier Control Room Klystron Gallery For EP, Clean Room underground space for Linac phase 1 & 2

STF Phase 1 Weld connection Valve Box 45MV/m Low-loss cavities 35MV/m TESLA-type cavities First test at KEK of assembling all components 2 cryomodules (connected each other) each containing 4 cavities of TESLA-type and LL-type Construction Operation 2007

STF Phase 2 (2007-9) Plan: construct 1 RF unit of ILC 1 bouncer-type modulator, 1 multi-beam 10MW klystron 3 cryomodules each containing 8 cavities Cavity type: TESLA or LL (to be decided in 2007) Design 2007 (during operation of phase 1) Construction )

STF Infra-structure Clean room : New clean room completed in Mar.2006 EP: New EP(Electro Polishing) facility, start construction in 2006 To be used for STF Phase 2 cryomodule production and other SC cavities for other projects (KEKB, crab, ERL,...) Chemical treatment room EP bed of ILC Clean room for cavity assembly cryomodule assembly carry hatch expansion clean room construction

R&D Items at ATF Emittance improvement of extracted beam (SLAC) Longitudinal feedback for stabilization of extracted beam (SLAC) Fast kicker (SLAC,LLNL) Polarized electron source (Nagoya) Polarized positron generation (Europe?) Bunch-by-bunch feedback system (Oxford) Laser wire (Kyoto, QMUL) Cavity BPM (SLAC, Tohoku Gakuin)

R&D Items at ATF2 Beamline design (SLAC) Quadrupole magnets (IHEP, SLAC) Q-BPM (PAL, SLAC) IP-BPM IP Beam size monitor Stable/reliable power supply (SLAC) Stabilization of final doublet quadrupole (France, CERN)

R&D Items at STF MBK (multi-beam klystron) development Baseline cavity fabrication with new coupler and tuner Development of LL (Low Loss) single-cell cavity Development of LL (Low Loss) 9-cell cavity with new coupler and tuner Fabrication of Nb/Cu-clad seamless cavity Photocathode system development