1. Baseline Configuration - Highlights Barry Barish ILCSC 9-Feb-06

2. ILCSC2 The Key Decisions Critical choices: luminosity parameters & gradient

3. 9-Feb-06ILCSC3 Making Choices – The Tradeoffs Many decisions are interrelated and require input from several WG/GG groups

4. 9-Feb-06ILCSC4 The Baseline Machine (500GeV) not to scale ~30 km e+ undulator @ 150 GeV (~1.2km) x2 R = 955m E = 5 GeV RTML ~1.6km ML ~10km (G = 31.5MV/m) 20mr 2mr BDS 5km

5. 9-Feb-06ILCSC5 Parametric Approach A working space - optimize machine for cost/performance

6. 9-Feb-06ILCSC6 Electron Source Positron-style room- temperature accelerating section diagnostics section standard ILC SCRF modules sub-harmonic bunchers + solenoids laser E=70-100 MeV DC Guns incorporating photocathode illuminated by a Ti: Sapphire drive laser. Long electron microbunches (~2 ns) are bunched in a bunching section Accelerated in a room temperature linac to about 100 MeV and SRF linac to 5 GeV.

7. 9-Feb-06ILCSC7 Positron Source Primary e - source e - DR Target e - Dump Photon Beam Dump e + DR Auxiliary e - Source Photon Collimators Adiabatic Matching Device e + pre- accelerator ~5GeV 150 GeV100 GeV Helical Undulator In By-Pass Line Photon Target 250 GeV Positron Linac IP Beam Delivery System Keep Alive: This source would have all bunches filled to 10% of nominal intensity. Helical Undulator Based Positron Source with Keep Alive System

8. 9-Feb-06ILCSC8 ILC Small Damping Ring Multi-Bunch Trains with inter-train gaps

9. 9-Feb-06ILCSC9 ILC Damping Ring: Baseline Design Positrons: – Two rings of ~6 km circumference in a single tunnel. – Two rings are needed to reduce e- cloud effects unless significant progress can be made with mitigation techniques. – Preferred to 17 km dogbone due to: Space-charge effects Acceptance Tunnel layout (commissioning time, stray fields) Electrons: – One 6 km ring.

10. 9-Feb-06ILCSC10 Main Linac: SRF Cavity Gradient Cavity type Qualified gradient Operational gradient Length*energy MV/m KmGeV initialTESLA3531.510.6250 upgradeLL4036.0+9.3500 * assuming 75% fill factor Total length of one 500 GeV linac  20km

11. 9-Feb-06ILCSC11 Cavity: R&D Material R&D: Fine, Large, Single Crystal Fabrication –A number of minor modifications and improvements could be implemented without impact to the basic cavity design. Cavity Preparation Buffer Chemical Processing Cavity Processing (strong R&D needed) –Electro-polishing (EP) System –High Pressure Rinsing (HPR) –Assembly Procedure

12. 9-Feb-06ILCSC12 Superconducting RF Cavities High Gradient Accelerator 35 MV/meter -- 40 km linear collider

13. 9-Feb-06ILCSC13 Improved Processing Electropolishing Chemical Polish Electro Polish

14. 9-Feb-06ILCSC14 RF Power: Modulator Baseline Alternate The Bouncer Compensated Pulse Transformer Style Modulator Operation: an array of capacitors is charged in parallel, discharged in series. (~2m) Will test full prototype in 2006

15. 9-Feb-06ILCSC15 RF Power: Baseline Klystrons Thales CPI Toshiba Specification: 10MW MBK 1.5ms pulse 65% efficiency

16. 9-Feb-06ILCSC16 Increase diameter beyond X-FEL Increase diameter beyond X-FEL Review 2-phase pipe size and effect of slope ILC Cryomodule

17. 9-Feb-06ILCSC17 ILC Beam Delivery System Baseline (supported, at the moment, by GDE exec) –two BDSs, 20/2mrad, 2 detectors, 2 longitudinally separated IR halls Alternative 1 –two BDSs, 20/2mrad, 2 detectors in single IR hall @ Z=0 Alternative 2 –single IR/BDS, collider hall long enough for two push-pull detectors

18. 9-Feb-06ILCSC18 Conclusions -- BCD The baseline configuration for the ILC has been established and is document in the BCD (a 700+ page electronic document) We have put the BCD under configuration control and are evolving it now in a controlled manner The BCD also defines alternatives and the combination of the baseline and alternative will give good guidance for the ILC R&D program The BCD is now being used as the starting point and basis for the reference design / cost effort this year.