1. 5 th CLIC X-band collaboration meetingWalter Wuensch16 May 2011 CLIC rf structure program

2. 5 th CLIC X-band collaboration meetingWalter Wuensch16 May 2011 CLIC today Most feasibility issues for CLIC have been demonstrated, with good momentum on remaining open issues e.g. TD24, CTF3, stabilization. CDR writing underway (sigh). Linear collider (CLIC+ILC+accelerator+detector) study leader at CERN – Steinar Stapnes Solid support from CERN management. Next phase, with roughly five year time-scale, to move towards project is being planned. Working assumption – consistent with CERN MTP (Medium Term Plan) + 30% contributions from collaborators.

3. 5 th CLIC X-band collaboration meetingWalter Wuensch16 May 2011 CERN MTP (draft) for 2012-2016

4. 5 th CLIC X-band collaboration meetingWalter Wuensch16 May 2011 rf structures today Individual structures basically achieving specifications, both PETS and accelerating structures. Almost have baseline structure – some features still need to be demonstrated like accelerating structure compact couplers, include SiC loads. Structure fabrication at KEK/SLAC, CERN and soon Saclay. Testing at NEXTEF, NLCTA, ASTA, CTF3 and CERN klystron. Critical – no structure under test today!

5. 5 th CLIC X-band collaboration meetingWalter Wuensch16 May 2011 Main areas for next stage 1 Fully establish baseline structure - Test of fully featured CLIC_G. Remaining features are TD24, compact power couplers and SiC loads. Check dynamic vacuum (tricky). Verify tolerances, wakefield monitor performance and long range wakefield suppression. Statistics – We need numbers for production yield and to verify long-term behavior. Significant increase in high-power testing capability – at least 6 test stands operating in parallel. Machining/metrology infrastructure – At CERN or at collaborating laboratory for better in-house insight into key technologies. Cost studies Integration into modules

6. 5 th CLIC X-band collaboration meetingWalter Wuensch16 May 2011 Re-optimize high-gradient design – We only now have high- gradient data that really lets us do this. Current design made end 2007. This will probably be done while re-optimizing for an intermediate energy CLIC. Easily room for O(10%) effects in efficiency and cost. Need to understand effect of beam loading, experiment planned. Optimize process – Deeper understanding of breakdowns ready to help us optimize machining, chemical surface treatment, heat treatments and conditioning strategy. We have something that works but there is the potential to reduce conditioning time and save lots of money. Other types of X-band structures – Structures optimized to intermediate/early stage energies, crab cavity and bunch compressor cavity. Main areas for next stage 2

7. 5 th CLIC X-band collaboration meetingWalter Wuensch16 May 2011 Alternative baseline designs – We followed a path to get the highest gradient earliest. Not obvious if this gives highest performance, cheapest structure. Ongoing activities are DDS with Manchester and choke mode with Tsinghua. Are we in a local or a global optimum? Fundamental breakdown studies –Guide rf design through high- power scaling laws, process optimization and testing. Excellent training for young people, ties in diverse collaborators. Exotic structures – Alternative materials, standing wave, speed bumps, recirculation etc. Still the potential for a breakthrough. Depending on LHC results a 3 TeV range machine may be proceeded by two lower energy stages – which means decades to get some of this stuff to work. Outreach – Good to spread X-band and high-gradient technology to other applications. Increased experience, increased credibility and lower cost. Obligation to give return on our R&D. Main areas for next stage 3

8. CLIC meetingWalter Wuensch6 May 2011 XFEL energy linearization – PSI and Trieste XFEL compact 1 kHz nc linac – Groningen High-gradient normal conducting cavities for carbon ion acceleration – TERA High-gradient normal conducting cavities – Muon collider High-gradient superconducting cavities – ILC CLIC collaborations with other projects

9. CLIC meetingWalter Wuensch6 May 2011 A scenario for high-power testing In my personal opinion increasing our testing capability is the most crucial issue we currently face. If we have enough test slots the rest will follow.

10. CLIC meetingWalter Wuensch6 May 2011 Work package planning I will now show the technical program broken down into DRAFT work packages. The work packages will be used to plan resources with CERN departments and groups and to establish and structure collaborations. The packages are NOT in their final form. On the largest scale they are getting close, details are not always so good (which doesn’t really matter).

11. X-band Rf structure Design

12. X-band Rf structure Production

13. X-band Rf structure High Power Testing

14. Creation and Operation of x-band High power Testing Facilities

15. Basic High Gradient R&D & Outreach

16. Creation of an “In-House” TBA Production Facility

17. Miscellaneous RF Overall material total 38.6 MCHF (out of 85.6x1.3=111 MCHF)