ILC Crab Cavity Collaboration

1. ILC Crab Cavity Collaboration • Cockcroft Institute : • Richard Carter (Lancaster University) • Amos Dexter (Lancaster University) • Graeme Burt (Lancaster University) • Imran Tahir (Lancaster University) • Philippe Goudket (ASTeC) • Peter McIntosh (ASTeC) • Alex Kalinin (ASTeC) • Carl Beard (ASTeC) • Lili Ma (ASTeC) • Roger Jones (Manchester University) • FNAL • Leo Bellantoni • Mike Church • Tim Koeth • Timergali Khabiboulline • Nikolay Solyak • SLAC • Chris Adolphson • Kwok Ko • Zenghai Li • Cho Ng LC-ABD plenary April 2007

2. Crab System Development FY04-07 (LC-ABD1 UK) • Initial study of a proposed ILC crab cavity solution has involved the design/simulation, and subsequent low power testing (i.e. without beam) of suitable cavity models. • Wakefield budget identified and coupler requirements • specified. • The phase control stability requirements have been defined for 14 mR and a prototype digital DSP/FPGA • LLRF system developed (tests expected in Q2 2007). LC-ABD plenary April 2007

3. FY07-10 (LC-ABD2) PPARC (STFC from Apr 1st) have committed to a constrained 3-year funding plan: – Crab cavity has survived at half funding! – Significant funding profile implications. • FY07-10 (LC-ABD2) funding can facilitate fabrication of a SRF crab cavity (incl. ancillaries) BUT ….. • UK funding will not allow for: – Cryomodule R&D – High power RF R&D LC-ABD plenary April 2007

4. FY07-10 (LC-ABD2 UK) • • EDR Priorities: • – Develop suitable coupler designs (CI/FNAL/SLAC): • • Verification by prototyping • – Iterate on optimum cavity geometry design (CI/FNAL/SLAC): • • Verification by prototyping with optimum couplers • – Develop suitable frequency and field orientation tuners (CI/FNAL): • • Verification by prototyping with optimum cavity design • – Develop suitable LLRF phase control system (CI): • • Verification by testing with 2 x SRF single-cell crab cavities (vertical test) • • Verification by testing with 2 x SRF 1.3 GHz TM010 cavities (ERLP @ DL) • – Fabrication of a single SRF crab cavity, incl. couplers and tuners, ready • for cryomodule integration (CI): • • Verification by vertical test qualification LC-ABD plenary April 2007

5. FY07-10 (US) • • EDR Priorities: • – Develop suitable cryomodule design and integrate cavity string (FNAL): • • Verification by beam tests on ILCTA @ FNAL • – Develop and procure suitable HP RF delivery scheme (CI/FNAL) • • Verification by specification definition and subsequent beam tests on • (ILCTA @ FNAL) • – Fabricate a 2nd crab cavity module and HP RF delivery system (FNAL) • • Verification of complete system performance on ILCTA @ FNAL • • Beam loading effects are critical to the performance of • the crab system and must be evaluated. • • ILCTA availability will drive these deliverables! LC-ABD plenary April 2007

6. Challenges and Synergies • • LLRF phase and synchronisation stability • • Couplers: • – Input – RF power • – LOM – peak magnetic fields • – SOM – damping • – HOM – fabrication and multipactor • • Tuning • – Field polarisation • • Cryomodule: • – Microphonics rejection LC-ABD plenary April 2007

7. Milestones • Goal 1. Design build and test Input, HOM, LOM and SOM couplers. • Milestones • 1.1 Apr 08: Coupler designs complete • 1.2 Apr 09: Component prototype testing complete • 1.3 Sep 08: Niobium coupler manufacture complete • 1.4 Apr 09: Integration onto SCRF cavity complete • Goal 2. Phase Control System development • Milestones • 2.1 Sep 07: System simulations complete • 2.2 Apr 08: Hardware manufacture complete • 2.3 Dec 08: Final manufacture and provisional testing complete • Goal 3 Design build and test cavity, couplers and cavity tuners • Milestones • 3.1 Apr 08: Cavity design complete • 3.2 Apr 09: Coupler testing complete • 3.3 Apr 09: Cavity tuner development complete • 3.4 Dec 09: Final manufacture and string assembly complete • 3.5 Mar 10: TDR report complete

8. Budget (at level funding for 3 years)