1. Global Design Effort Beam Delivery System & Machine Detector Interface Andrei Seryi, SLAC Annual DOE HEP Program Review June 11-14, 2007

2. Global Design Effort BDS & MDI: 2 2007 DOE review Plan of the talk Overview of Beam Delivery System design Highlight contribution of SLAC team to RDR design of practically all subsystems of BDS Describe ATF2 and ESA facilities and SLAC role Show integration of SLAC and Americas efforts into global efforts on Beam Delivery

3. Global Design Effort BDS & MDI: 3 2007 DOE review BDS layout Single IR push-pull BDS, upgradeable to 1TeV CM in the same layout, with additional bends Design of central area is done with major contribution from SLAC CFS group

4. Global Design Effort BDS & MDI: 4 2007 DOE review BDS beamline 14mr IR FF E-collimator  -collim. Diagnostics Tune-up dump BSY Sacrificial collimators Extraction grid: 100m*1m SLAC experience with SLC and FFTB allow SLAC to contribute to various aspects of ILC BDS design Optics design of BDS beamlines done almost entirely at SLAC

5. Global Design Effort BDS & MDI: 5 2007 DOE review BDS optics for incoming beam FF E-collimator  -collim. Diagnostics BSY Polarimeter E-spectrometer FF optics is based on a local chromaticity compensation design suggested at SLAC

6. Global Design Effort BDS & MDI: 6 2007 DOE review Machine Detector Interface Strong expertise on MDI issues at SLAC –beam background –Luminosity, E, and polarization diagnostics –machine detector integration Will show two examples where, during RDR design optimization, the MDI issues were analyzed, with significant participation of SLAC group, and design changes suggested, resulting in large cost saving or schedule improvement –muon protection –detector assembly

7. Global Design Effort BDS & MDI: 7 2007 DOE review Muon walls Analysis of detector background for likely beam halo have shown that initial installation can include single 5m walls, which gave significant saving w.r.to initial configuration of 9+18m walls. Have space to install second 9m wall and upgrade 5m wall to 18m if background level will be measured to be too high. Purpose: –Personnel Protection: Limit dose rates in one IR when beam sent to other IR or to the tune-up beam dump –Physics: Reduce the muon background in the detectors Magnetized muon wall

8. Global Design Effort BDS & MDI: 8 2007 DOE review photos courtesy CERN colleagues Detector assembly CMS detector assembled on surface in parallel with underground work, lowered down with rented crane Adopted this method for ILC, to save 2-2.5 years that allows to fit into 7 years of construction This also allowed to optimize & reduce CFS EXP cost SiD and other detector concepts implementing this strategy into their design

9. Global Design Effort BDS & MDI: 9 2007 DOE review IR integration Integrated design of Interaction Region will be one of the main focus points of SLAC activity in EDR IR integration design work will be done in collaboration with BNL, developing IR SC magnets, and with Detector concepts Single IR push-pull configuration pose specific challenges to this work Goal is to evolve from concept level cartoons, shown on next slides, to cost and performance optimized detailed engineering design

10. Global Design Effort BDS & MDI: 10 2007 DOE review IR integration, a start (old location) Started IR integration work at SLAC, in close collaboration with BNL and other partners

11. Global Design Effort BDS & MDI: 11 2007 DOE review Design and prototyping of IR compact SC magnets is led by BNL (Brett Parker et al) Accelerator physics optimization of IR magnets is done in very closed and fruitful collaboration of BNL and SLAC Shield ON Shield OFF Intensity of color represent value of magnetic field. Actively shielded QD0 to be prototyped new force neutral antisolenoid

12. Global Design Effort BDS & MDI: 12 2007 DOE review IR integration For IR integration, a task force was formed with BNL colleagues and SLAC cryo and mechanical engineers & physicists. With emerging EDR organization, this task force will be streamlined Service cryostat & cryo connections BNL

13. Global Design Effort BDS & MDI: 13 2007 DOE review Workshop on ILC Interaction Region Engineering Design SLAC, September 17-21, 2007 Goal: To review and advance the design of the subsystem of the Interaction Region of ILC, focusing in particular on their integration, engineering design and arrangements for push-pull operation. … goal is to make progress on the design of the ILC IR through focused preparation before and during the workshop… The International Program and Advisory Committee is being formed. Its charge includes organization of preparatory work before the workshop and production of conceptual solutions and drawings that could be further discussed and reviewed at the workshop… –this is an attempt to align the organization of the workshop with EDR organization http://www-conf.slac.stanford.edu/ireng07/

14. Global Design Effort BDS & MDI: 14 2007 DOE review BDS subsystems & test facilities Several subsystems of BDS will require focused work & prototypes in EDR phase – IR magnets, crab cavity, beam dump, collimators… BDS system test – ATF2 facility at KEK BDS/MDI facility – ESA at SLAC SLAC team is involved in major part of these activities Overall system design, system engineering and integration will be major

15. Global Design Effort BDS & MDI: 15 2007 DOE review Evaluation of different designs and optimization of couplers to reduce sensitivity to notch filter gap (Z.Li et al, SLAC) old / new HOM coupler Crab cavity design 3.9GHz 9-cell cavity in Opega3p, (K.Ko et al, SLAC) Challenges: LLRF phase and synchronization stability –Required phase stability ~67fsec or 0.094 o for <2% luminosity loss (7 cell 1.5GHz cavity at the JLab ERL achieved a 37fsec) Couplers, tuning, cryomodule Design & EDR work will be done by UK- FNAL-SLAC collaboration 3.9GHz cavity achieved 7.5 MV/m (ILC operating field at 500GeV/beam is 5MV/m (FNAL)

16. Global Design Effort BDS & MDI: 16 2007 DOE review Beam dump Design is based on MW dump designed and built at SLAC ILC beam dump features –17MW power; rastering of the beam on 30cm double window; upstream donut collimators –6.5m water vessel; 1m/s flow; beam 0.3m off-center; 10atm prevent boiling; –three loop water system; catalytic H 2 -O 2 recombiner; filters for 7Be; –Shielding 0.5m Fe & 1.5m concrete EDR work will include physics & engineering design, studies of window irradiation and possibly prototyping the front-end of the windows exchange mechanism

17. Global Design Effort BDS & MDI: 17 2007 DOE review ATF2 Scaled down model of ILC final focus

18. Global Design Effort BDS & MDI: 18 2007 DOE review ATF2 facility ATF2 will: –prototype FF –help development tuning methods, instrumentation (laser wires, fast feedback, submicron resolution BPMs), –help to learn achieving small size & stability reliably, –potentially able to test stability of FD magnetic center. ATF2 is one of central elements of BDS EDR work, as it will address a large fraction of BDS technical cost risk. Constructed as ILC model, with in-kind contribution from partners and host country providing civil construction SLAC contributions to ATF2 include –Design of optics; high availability PS; magnets for FD; bends; electronics for BPMs; movers for magnets; –commissioning & operation ATF2 commissioning will start in Autumn of 2008

19. Global Design Effort BDS & MDI: 19 2007 DOE review J.Nelson (at SLAC) and T.Smith (at KEK) during recent "remote participation" shift. Top monitors show ATF control system data ATF & ATF2 T.Smith is commissioning the cavity BPM electronics and the magnet mover system at ATF beamline

20. Global Design Effort BDS & MDI: 20 2007 DOE review BDS beam tests at ESA Runs: three 2-weeks runs in 2006 & 07; request two runs in 2008 Latest run: March 7-26, 2007 ~ 40 participants BPM energy spectrometer (T-474/491) Synch Stripe energy spectrometer (T-475) Collimator design, wakefields (T-480) IP BPMs/kickers—background studies (T-488) EMI (electro-magnetic interference) Bunch length diagnostics (T-487) more in talk of M.Woods

21. Global Design Effort BDS & MDI: 21 2007 DOE review interferometer Energy spectrometer at ESA BPM & SR based Interferometer metrology grid for BPMs NMR probes in magnets 0.5um BPMs with  =5mm => 1e-4 energy resolution Study calibrations, systematics, stability SR version with quartz fiber detector will be used next run BPM magnet of the chicane

22. Global Design Effort BDS & MDI: 22 2007 DOE review Collimation wakefield study in ESA Results from 2006 run: –measurements, analytics & 3d modeling differ by up to factor of 2 March 2007 run was focused on tests of –importance of tapers in region away from gap center –tapers with shallow part only near beam axis –explicit tests of surface roughness –non-linear exponential form taper Results are being analyzed

23. Global Design Effort BDS & MDI: 23 2007 DOE review Integration of SLAC efforts SLAC efforts are integral part of Americas efforts on BDS design Main collaborators in Americas are BNL and FNAL –contacts with TRIUMF are being established –Universities contribute to MDI experiments Americas efforts are well integrated into worldwide efforts on BDS –optimization of work distribution is being done, with help of BDS area leaders and GDE S4 task force

24. Global Design Effort BDS & MDI: 24 2007 DOE review R&D in BDS and global collaboration Development of IR SC magnets, integration into the IR, design study to ensure their mechanical stability. US only, US lead development of crab cavities, and related systems to provide phase stability. US in collaboration with UK as equal partners design, construction, commissioning and operation of BDS facility (ATF2). US in collaboration with Asia and Europe, Asia lead accelerator physics design work which enable performance optimization. US in collaboration with Asia and Europe, US lead measurements of collimator wakefield and their validation with codes. US in collaboration with UK, UK lead study of collimator beam damage and damage detection. US in collaboration with UK, as equal partners development and tests of MDI type hardware such as energy spectrometers. US in collaboration with UK, as equal partners Development of laser wires for beam diagnostics. No significant US involvement, UK lead. development of intratrain feedback. No significant US involvement, UK lead design of beam dumps. US, Canada (discussed) & UK as equal partners

25. Global Design Effort BDS & MDI: 25 2007 DOE review Summary Beam Delivery System design was produced for RDR, with significant contribution from SLAC team SLAC group critically involved in many subsystems of BDS and into machine detector integration SLAC and Americas efforts are well integrated into global efforts on Beam Delivery SLAC is ready to take the leadership role in the design, construction and operation of Beam Delivery System area of ILC