Beam Delivery System Review of RDR(draft) 1.Overview 2.Beam parameters 3.System description 3.1 diagnostic, tune-up dump, machine protection MPS collimation Skew correction Emittance diagnostcs Polarimeter and energy diagnostics Tune-up and emergency extraction system 3.2 Collimation system Muon suppression Halo power handling Tail-folding octupoles 3.3 Final focus 3.4 IR design and integration to detector 3.5 Extraction line 4.Accelerator components 4.1 Crab cavity system 4.2 Feedback system and stability Train-by-train feedback Intra-train IP position and angle feedback Luminosity feedback BDS entrance feedback( ‘train-straightener’) Hardware implementation for intra-train feedbacks 4.3 Energy, luminosity and polarization measurements Energy measurements Luminosity measurements Polarization measurements 4.4 Beam dumps and collimators 4.5 BDS magnets BDS magnets: tail-folding octupoles 4.6 Vacuum system Wakes in vacuum system Beam-gas scattering Vacuum system design 4.7 IR arrangements for two detectors 4.8 Diagnostic and correction devices RDR contents S.Kuroda

1.Overview Single IP(14mrad) and push-pull detector measure the linac beam and match it into the final focus; protect the beamline and detector against mis-steered beams from the main linacs; remove any large amplitude particles (beam-halo) from the linac to minimize background in the detectors; measure and monitor the key physics parameters such as energy and polarization before and after the collisions; Squeeze beam at IP to  x=639nm,  y=6.7nm RDR

IR 14 mrad 14 mrad ILC FF9 hybrid (x 2) 14 mrad (L* = 5.5 m) dump lines detector pit: 25 m (Z) × 110 m (X) e-e+ hybrid “BSY” (x 2) 2226 m ΔZ ~ -650 m w.r.t. ILC2006c M.Woodley

2.Beam Parameters RDR

3.System Description polarimeter skew correction / emittance diagnostic MPS coll betatron collimation fast sweepers tuneup dump septa fast kickers energy collimation β-match energy spectrometer final transformer final doublet IP energy spectrometer polarimeter fast sweepers primary dump Main Linac ILC2006e electron BDS schematic energy collimation M.Woodley

3.1 Diagnostic, Tune-up Dump, Machine protection polarimeter skew correction / emittance diagnostic MPS coll β-match Main Linac betatron collimation extraction angle = mrad L B =2.4 m (×3) ΔL BB = 0.3 m Compton IP 250 GeV x = 20 mm 76.9 m MPS Ecoll ±10% 8 m 3 m laserwire detector 16.1 m 35 GeV 25 GeV Cerenkov detector 2 m 12.3 cm 18.0 cm ΔE/E BPM  optics Polarimeter chicane  M.Woodley

3.2 Collimation System To remove Halo particles( BG of detector ) SR which hits detector Betatron Collimator Spoiler/Absorber pair at high beta points Energy Collimator Single spoiler at high dispersion point Collimation depth 8-10  x,  y Muon suppression 5m long magnetized iron filled in tunnel Tail-folding octupole Non-linear focusing of halo particles Core part of the beam unaffected

3.3 Final Focus RDR Local chromaticity correction Correction of geometric aberration, 2nd order dispersion and higher order aberration

3.4 IR Design and Integration to Detector FD: compact superconducting magnet inside detector First cryostat is attached to detector Solenoid effect to beam anti-solenoid, DID, anti-DID RDR

3.5 Extraction Line RDR Transport beam to dump Diagnostics Energy measurement at 1st v-chicane Polarimetry at 2nd IP( R22=-0.5 )

4. Accelerator Components 4.1 Crab Cavity System To make head-on collision Two 3.9GHz SC 9-cell cavities Crab cavity prototype(RDR)

4.2 Intra-train Feedback Measurement of beam-beam deflection  stripline kicker FONT4: R&D with digital board processor Test is on-going at ATF. Goal latency is 140ns P.Burrows et al 4.3 Polarization Measurement RDR ILC physics requires  Polarization measurement with 0.25% accuracy

4.4 IR Arrangements for two detectors RDR Detector Hall surface assembly Detector self-shield/shielding wall between detectors  maintenance when off beam-line

5. Solenoid Effect Orbit change at IP( in y )  Accuracy in polarization measurement For correction, Detector Integrated Dipole(DID) At higher energy, back-scattered e+e- pair  huge BG for detector DID with reversed polarity( anti-DID ) which align orbit to out-going beam line DID/anti-DID A.Seryi, B.Parker

Anti-Solenoid Overlapping of solenoid field with FD produces huge beam size blow-up. Anti-solenoid can correct the beam size growth excellently. The effect is independent on x-ing angle. With antisolenoids and linear knobs,  y = 0.9%  Y. Nosochkov, A. Seryi

6. Beam Tuning Beam tuning method is being studied by computer simulation BBA, Luminosity(beam size) tuning,… Example. BBA+Luminosity tuning with traditional method; Linear knob of SX mover + higher order knob Errors dx/dy for magnets=200um, roll=300urad, field error-1e-4, …….. Disp, Waist,, tilt dK Luminosity G.White

7. Issues for further Study Hardware Crab cavity system Feedback system SC magnets Monitors( LW,…) ……. Study of beam tuning, beam dynamics, BG,… Alternative design e.g. small x-ing angle/head-on collision including ES separator, large bore magnets for EXT Test facility ESA, ATF/ATF2,…..