Akira Yamamoto (KEK) for the ILC-GDE Project Managers

1. Global R&D Effort in the Technical Design Phase for the ILCI. OverviewII. Superconducting RF Development Akira Yamamoto (KEK) for the ILC-GDE Project Managers To be presented at the 2nd AISA ILC R&D Seminar, Deagu, September 29, 2008

2. I. Overview

3. Toward Technical Design Report Reference Design, 2007 --> Technical Design Phase, 2008-2012

4. Reference Design Report, published, 2007 • SC linacs: 2x11 km • for 2x250 GeV • Injector centralized • Circular damping rings • IR with 14 mrad crossing angle

5. Critical R&Ds in TDP • SCRF • High Gradient : 35 MV/m at the yield 90 % (S0) • Plug-compatibility • System Engineering (S1, S2) • Conventional Facilities & Siting • Tunnel: Deep/Shallow, Double/Single Tunnel • Accelerator Systems • Positron sources, • Low emittance: ATF, CESR-TA

6. Minimum Machine Study M. Ross for PM • Physics scope (WWS document) • 200-500 GeV centre-of-mass energy range • 2x1034 cm-2s-1 • polarized electrons • Identify cost-driving requirements and criteria • Push back on them to acceptable minimum • CFS will be primary target • Underground volume and construction • Process cooling water • Definition document due late 2008 • Led by Project Manager Nick Walker (DESY) and ILC Integration Scientist Ewan Paterson (SLAC)

7. Towards a Re-Baselining in 2010 Re-Baseline New baseline engineering studies RDR Baseline (VALUE est.) • Process • RDR baseline & VALUE element are maintained • Formal baseline • MM elements needs to be studies/reviewed internationally • Regional balance in the AP&D groups involved • Regular meetings and discussions (but top-down control from PM) • Formal review and re-baseline process beginning of 2010 • Exact process needs definition (a PM action item for 2009) • Community sign-off mandatory MM studies MM def (RDR ACD concepts and R&D) Non-baseline elements 2009 2010 2012

8. Main Linac Specific • Removal of support tunnel (single tunnel) • klystron cluster • XFEL-like • Dubna option (surface klystron gallery)? • Klystron Cluster (HLRF) • 30 klystrons located in localised surface buildings • ~300 MW RF power distributed in beam tunnel via over-moded waveguide • effectively ~1km RF unit • Marx modulator • Reduced cost solution for process-water cooling • Higher DT specification alternative options

9. High Power RF distribution using Over-moded waveguide cluster building The waveguides share a shaft down to the accelerator tunnel and then turn, one upstream and one downstream to feed, through periodic tap-offs, a combined 64 RF units, or ~2.5 km of linac. • service tunnel eliminated • underground heat load greatly reduced shaft upstream downstream accelerator tunnel

10. Minimum Machine: Current Definition • “Minimum Machine” now refers to a set of identified options (elements) to be studied which may reduce the cost. • Not a minimum in a definable sense • But a potential reduced-cost solutions… • with a potential higher performance risk or operational impact • An alternative design (ACD-like) for study purposes • Comparison with RDR baseline • Cost (not performance) driven • options which were not studied during RDR phase • Important to restrict options to manageable levels • available resources • Must consider both peak and integratedperformance Other “VALUE Engineering” Activities (parallel)

11. 2. SCRF

12. SCRF: Outline • Requirements • R&D Status • Fundamental research with single-cell cavities • Progress in 9-cell cavities • Plan for Technical Design Phase • High Gradient, • Plug-compatible Engineering • Global Plan and Effort • Summary

13. TDP Goals of ILC-SCRF R&D • Field Gradient • 35 MV/mfor cavity performance (S0) • 31.5 MV/m (10 % lower) for operational gradient • to build two x 11 km SCRF main linacs • Cavity & Cryomodule Integration with • “Plug-compatible” concept to: • Encourage “improvement” and creative work in R&D phase • Motivate practical ‘Project Implementation’ to share intellectual work in global effort • Accelerator System Engineering andTests • Cavity-string in one cryomodule (S1, S1-global) • Cryomodule-string with Beam Acceleration (S2) • With one RF-unit containing 3 crymodule

14. Cavity Shape Design Investigated • TESLA • Lower E-peak • Lower risk of field emission • LL/IS, RE • Lower B-peak • Potential to reach higher gradient LL: low-loss, IS: Ichiro-shape, RE: re-entrant

15. Progress in Single Cell Cavity • Record of 59 MV/m achieved with the RE cavity with EP, BCP and pure-water rinsing with collaboration of Cornell and KEK • (K. Saito, H. Padamsee et al. , SRF-07)

16. R&D Status of 9-Cell Cavity • Europe • “Gradient” improved (<31.5> MV/m) with Ethanol rinse (DESY): • Large-grain cavity (DESY) • Surface process with baking in Ar-gas (Saclay) • Industrial (bulk) EP demonstrated (<36> MV/m) (DESY) • America(s) • Basic research and surface process (Cornell, JLab, Fermilab) • Field emission reduced with Ultrasonic Degreasing using Detergent, and “Gradient” improved (JLab) • Large-grain cavity (<36> MV/m) (JLab) • Surface process facility (Fermilab/ANL) • Vertical (cold) test facility with thermometry (Fermilab) • Asia • “Gradient” demonstrated, 36MV/m (LL, KEK-JLab), and 28 MV/m (TESLA-like in cryomodule, KEK) • Optical inspection system (KEK)

17. “Operational Field Gradient” in progress at TESLA/FLASH toward EuroXFEL ILC operation： • <31.5> MV/m R&D Status： • ~ 30 MV/m to meet XFEL requirement • We need 20 % improvement to meet ILC requirement

18. DESY: Field Emission Analysis • MV/m 30 40 Cavity gradient shifted to High Gradient by ‘ethanol rinse’, except for “lowest two” (due to different reasons)

19. Industrial EP at DESY/Plansee • The average gradient, 36 MV/m, achieved with AC115-118

20. 9-cell Progress in American Laboratorieswith Japanese contribution for ICHIRO-5 A (Accell), AES: TESLA shape, ICHITO: LL shape 24

21. 9-cell LL Cavity, Ultrasonic Degreasing“ICHIRO-5” Studies at JLab-KEK Ultrasonic Cleaning with degreaser very effective to reduce field emission

22. TESLA-like 9-Cell Cavity at KEK Cryomodule/Horizontal test Result June 30 – July 25. 2008: with warm coupler and klystron connection for only BL#2: 28 MV/m achieved

23. SCRF Activities in Asia • Participation in STF at KEK • Cryomodule and coupler design (IHEP) • 9-cell cavity fabrication (PAL) • LL single cell (IHEP) • Cavity design/processing (PNU/KNU) • Joining STF operation (RRCAT) • China • Cavity fabrication (Deep drawing, EBW, CB) (IHEP,PKU.) • Large grain cavity (Ningxia, PKU) • Korea • Works other than SCRF (RTML design, cavity BPM, DR) • India • Nb material investigation • Cavity fabrication in cooperation with FNAL • Cavity process in cooperation with KEK

24. Outline • Introduction • R&D Status • Fundamental research (with single cell cavities) • Progress in 9-cell cavities • Plan for Technical Design Phase • High Gradient, • Plug-compatible Engineering • Global Plan • Summary

25. Plan for Further High Gradient R&D 1: Research/find cause of gradient limit for quench: high resolution camera for field emission: further surface analysis 2: develop countermeasures for quench: remove beads & pits, 3: verify countermeasures exchange problem/information 4: Integrate the countermeasures install the countermeasure world-wide and get statistics

26. A New High Resolution, Optical Inspection System For visual inspection of cavity inner surface. motor & gear for mirror camera & lens ~600µm beads on Nb cavity EL EL Camera system (7µm/pix) in 50mm diameter pipe. white LED half mirror camera sliding mechanism of camera mirror perpendicular illumination by LED & half mirror tilted sheet illumination by Electro-Luminescence Iwashita (Kyoto) and Hayano (KEK) et al.

27. Guideline: Standard Procedure and Feedback Loop w/o optical inspection

28. Guideline: Standard Procedure and Feedback Loop w optical inspection w optical inspection w optical inspection

29. Comparison with each treatment #4 cell equator, Z=516mm, t=103 deg EP-1 (25 + 100 um removed) EP-1 (25 um removed) After Fabrication

30. Progress and Plan forCavity-Cryomdule Integration • Europe (EU) • Input-coupler industrial assessment for XFEL (LAL-Orsay) • America(s) (AMs) • Cryomodule design (FNAL) • Cryogenic engineering (FNAL in cooperation with CERN) • SCRF Test Facility (FNAL) • Asia (AS) • Cryomodule engineering design (KEK/IHEP) • Superconducting test facility (KEK) • A global effort for Cavity/Cryomodule Assembly • Plug-compatible integration and test in cryomodule:

31. Plug-compatibly of Cavities Important for Global Cooperation Plug-compatible interface need to be established

32. Plug compatible conditions at Cavity package (example)

33. Why “Plug compatible” Integration and Engineering ? • Encourage R&D effort specially to improve the “gradient” • Cavity Type: Tesla, Low-loss (Ichiro), Re-entrant • Material: Fine-grain or large grain • Preparation: EP, Rinsing, • Tuner type: various designed w/ various arguments, • Input-coupler: Fixed, Tunable, However, • The “plug –compatible” concept is important, • Beam pipe, cryogenics, and RF connections: need to be “plug-compatible” • Cavity-Integration in Cryomodule: R&D inglobal effort

34. Intending “plug-compatibility” • Cavity • Status: still in “basic research” to improve field gradient (limit), • Establish: unified interface conditions, • Keep: “room” to improve field gradient, • Cryomodule • Status: ready for “system engineering” • Establish: unified interface conditions, • Intend: nearly identical engineering design • But: need to adapt to each regional industrial constraints (for example: High Pressure Code)

35. Cavity and Cryomodule Performance Testwith Plug Compatibility, in Global Effort • Cavity integration and the String Test to be organized with: • 2 cavities from DESY and Fermilab • 4 cavities from KEK • Each half-cryomoducle from INFN and KEK

36. Beam Acceleration Test with one RF Unit (S2) Plan for KEK-STF-2 in ILC-TDP2

37. Outline • Introduction • R&D Status • Fundamental research (with single cell cavities) • Progress in 9-cell cavities • Plan for Technical Design Phase • Cavity Gradient, • Plug-compatible Engineering • Global Plan and Effort • Summary

38. Global Plan for SCRF R&D

39. Cooperation with EuroXFEL and Other Projects European X-ray Free Electron Laser Facility • EuroXFEL SRF design gradient：　25 MV/m • ~ 100 SCRF cryomodule, based on the experience at TTF, DESY, • Leading SCRF industrialization (scale: 1/20 of ILC, in coming 5 years) • Keep close cooperation with XFEL, on-going project. Further SCRF Accelerator Project Plans investigated: • Project X at Fermilab, SC Proton Linac at CERN, and ERL at KEK

40. Summary • Technical Design Phase in progress: • Phase-1: Technical reality to beexamined, • 35 MV/m with yield 50 % for 9-cell cavity and • < 31.5 MV/m> with the cavity-string in a cryomodule • Plug-compatible crymodule to be examined with global effort. • Phase-2: Technical credibility to be verified • 35 MV/m with the yield 90 % for 9-cell cavity field gradient of • System engineering and beam acceleration with one RF unit and 3 cryomodules with the field gradient <31.5> MV/m. • We aim for • Global cooperation for the ILC SCRF technology with having plug-compatibility, and with scoping smooth extension to the ILC construction/production phase.

41. Backup

42. ILC-GDE Project Management in TDP ILC Council (ILCSC) Funding Agencies and Institutions Global Design Effort Accelerator Advisary Panel Executive Committee Membership: TBD Director Project Management Office EDMS Cost Management Asia Americas Europe SCRF CF&S Acc. Sys. Instit. …. Institution Institution Institution Instit. ….