1. N.Solyak, RTML OverviewBTW review, DESY, Oct. 24-27, 2011 1 ILC RTML overview Nikolay Solyak Fermilab RTML functions, RDR and SB2009 designs Beamlines overview Bunch compressors Emittance preservation in RTML Stray magnetic fields studies Technical systems: Vacuum, Magnets, Etc. Summary Last version, Oct.24

2. BS2009 beam parameters N.Solyak, RTML Overview BTW review, DESY, Oct. 24-27, 2011 2

3. N.Solyak, RTML Overview BTW review, DESY, Oct. 24-27, 2011 3 RTML Functions Transport Beam from DR to ML –Match Geometry/Optics Collimate Halo Rotate Spin Compress Bunch Preserve Emittance –vertical norm.emittance < (4-6)nm Protect Machine –3 (2) Tune-up / MPS abort dumps Additional constraint: –Share the tunnel with e-,e+ injection lines –Need to keep geometries synchronized Footprint ~30km RDRSB2009 In SB2009 some inconsistencies were fixed (Turnaround orientation)

4. New conventions for RTML names (B.List) N.Solyak, RTML Overview BTW review, DESY, Oct. 24-27, 2011 4 Note: e- and e+ RTMLs have minor differences in Return line (undulator in e- linac side), they are otherwise identical. HDOG & VDOG

5. Changes in RTML configuration (SB2009 vs. RDR) N.Solyak, RTML Overview BTW review, DESY, Oct. 24-27, 2011 5 Central area (Lines from DR extraction to ML tunnel) RDR: DRX (100m)+Getaway(1100m share with sources )+Elevator (590m) SB2009: ERTL/PLTR is short (~170m) - Vertical merger in positron line (PRTL) to merge beams from 2 DR’s. Straight in electron line (ERTL) - Extraction to dump moved closer to DR and modified, (like BC1S extraction) - Dump line design is similar to BC1S dump Skew Corr, Emittance Diagnostics and Collimation sections are moved to BDS/ML tunnel and combined with Return Line ( ELRL/PLRL) Length of “Return line” is adjusted to Linac length in ML tunnel ETURN/PTURN (“Turnaround”): V-DOGLEG and H-DOGLEG parameters are modified to fit new RTML-to-ML separation in tunnel BC1S: Single-stage Bunch Compressor. Removed one diagnostics section and Dump Line (from BC2 line) Re-designed Dump line from BC1S to accommodate larger (3.4%) energy spread Acceleration from 4.4 GeV to 15 GeV belongs now to ML

6. New Central Area General Layout N.Solyak, RTML Overview BTW review, DESY, Oct. 24-27, 2011 6 Figure 1: August 16, 2011 draft drawing by the CF&S group of the proposed central region layout. In this drawing the PLTR and eRTML tunnel is to the left and the ELTR and pRTML tunnel is to the right.

7. 7 RTML lines in central area (PRTL/ERTL) Name SectionLength, [m] ,[m] / , [deg] A DR Extraction-- B e+ vert. merger80.021straight C 1 st Horiz. Arc13.35530 / 25.506 D Extraction45.068Straight E 2 nd Horiz. Arc21.45731 / 39.658 (F)PLTL-straight “Ideal” end-coordinates for e + XYZ , rad AB64.4100.350107.490-0.240 BC45.3891.650185.217- CD39.4781.650197.071- DE10.9591.650231.968- EF3.9631.650251.801+0.007 “Ideal” (arcs & straight lines) layout for e + for X DR =70.0m;  DE =0.007mrad N.Solyak, RTML Overview 7 BTW review, DESY, Oct. 24-27, 2011 (x,y,z=0,0,0 )

8. N.Solyak, RTML Overview BTW review, DESY, Oct. 24-27, 2011 8 ERTL (Electron-Ring-to-Linac) line Current design is almost planar (horizontal plane) DRs are is separated vertically by 1.3m: electron ring has the same elevation as RTML in ML tunnel Sources need cryomodules and SC solenoids, heavy objects sitting at floor (w orking agreement between sources, DR, RTML, CFS Positron Merger/Splitter e-e- e+

9. 9 Total merger: Preliminary design Total length can be reduced by using shorter bending magnets and adjusting angles Final design can be improved, needs specifications of “final merge” magnets. N.Solyak, RTML Overview 9 BTW review, DESY, Oct. 24-27, 2011 Pulsed kickers in last long period. Matched to D y =D’ y = 0;  =0. Vertical displacement =1.3m;

10. 10 Merger/Splitter: fast kicker and septum Make more flexible tuning by independent variation of the 15 th cell (B~400 Gs) N.Solyak, RTML Overview 10 BTW review, DESY, Oct. 24-27, 2011 C-shape Quad with 54mm beam separation (V.Kashikhin)

11. N.Solyak, RTML Overview BTW review, DESY, Oct. 24-27, 2011 11 “B”&“C”: Vertical merger and 1 st Horiz. arc Treaty point  x [m] 45.00  y [m] 29.96 xx -0.7989 yy +1.5752 “B”: “MATCH1”+ “e+ vert. merger”+”MATCH2” +”2 FODO cells” (2 FODO cell are borrowed from 1 st H-arc to adjust L B ) “C”: “8-bend H-arc”

12. 12 “D”&“E”: Extraction to Dump and 2 nd Horiz. arc N.Solyak, RTML Overview 12 BTW review, DESY, Oct. 24-27, 2011 Note: Dump Line are on the ceil  floor in dump alcove is higher than in tunnel

13. N.Solyak, new RTML: Ecentral matching ALCPG 2011,Oregon, Mar.18 13 Matching with Q-doublets 2 steps matching with quadrupole doublet: * Ph.J.Bryant, K.Johnsen, "The principles of circular accelerators and storage rings", 1993. a) approximate semi-analytical solutions* for Q-doublet (thin quadrupoles); b) refined numerical solutions using MAD8 matching commands (thick quadrupoles) Matching PLTR&ELTR layouts: a continuous solution for Q-doublets allows to adjust the total length of Q-doublet N.Solyak, RTML Overview 13 BTW review, DESY, Oct. 24-27, 2011

14. 14 ERTL/ PRTL survey results (MAD8) Good symmetry in X0Z plane between PRTL and ERTL (while the same L  ) N.Solyak, RTML Overview 14 BTW review, DESY, Oct. 24-27, 2011 Good coincidence between the “ideal” layout and the lattice survey

15. N.Solyak, RTML Overview BTW review, DESY, Oct. 24-27, 2011 15 ELRT: “Getaway” (or “DR Stretch”) About 460 m long In SB2009 are included in ELRT/PLRT (Long Return Transport line ) Has two parts –“Low-beta” region with decoupling and emittance measurement –“High-beta” region with collimation system Includes PPS stoppers –For segmentation Good conceptual design –Need to match exact required system lengths –Need to consider conflicts with source beamlines in this area Beam collimation Energy collimation Skew corrections and Emittance measurements * Length reduced to ~460m

16. N.Solyak, RTML Overview BTW review, DESY, Oct. 24-27, 2011 16 ELRT: Electron Long Return Transport “Return Line” Includes: –Skew Corr. (27m), Diagnostics (27m) –Energy / halo collimation (400m) –Return line (straight-curved-straight) “RETURN”- weak FODO lattice at ML ceiling elevation (1Q/~36m) Vertically curved tunnel thru ML area –Dispersion matching via dipole correctors Laser-straight tunnel thru BDS & BC area Electron line is longer than positron (?) due to undulator and (or) adjust timing –System lengths probably not exactly right (now ~31m longer) –FODO length in electron and positron lines are slightly different to adjust total length for timing e- ML Undulator 400 MeV e+ e- Return RTML–to-ML separation: Vertical = 1.65m (was 2.14) Horizontal 2.2m (was 1.44)

17. N.Solyak, RTML Overview BTW review, DESY, Oct. 24-27, 2011 17 ETURN: “Turnaround” Actually does 3 jobs –Turns the beam around Note: need to bend away from service tunnel –Brings beam down from ceiling to linac elevation (near floor) Vertical dogleg –Adjusts x position to meet linac line Horizontal dogleg –Order: H dogleg, V dogleg, turnaround –Packing area, ~90% magnets Spin Rotator H-dogleg V-dogleg z x z y

18. N.Solyak, RTML Overview BTW review, DESY, Oct. 24-27, 2011 18 Spin Rotation Design based on Emma’s from NLC ZDR –2 solenoids with Emma rotator between them –Rotate spin 90° in xy plane while cancelling coupling –8° arc –Rotate spin 90° in xz plane –Another 2 solenoids + Emma rotator Basic design seems sound –Very small loss in polarization from vertical bending in linac tunnel Important issue = bandwidth –Off-energy particles don’t get perfect cancellation of dispersion and coupling Diagnostics

19. N.Solyak, RTML Overview BTW review, DESY, Oct. 24-27, 2011 19 ILC Baseline 2-stage Bunch Compressor Longitudinal emittance out of DR: –6mm (or 9 mm) RMS length –0.15% RMS energy spread Want to go down to 0.2-0.3 mm Need some adjustability Use 2-stage BC to limit max energy spread –1 st : Compress to 1 mm at 5 GeV –2 nd : Accelerate to 15 GeV and Compress to final bunch length Both stages use 6-cell lattice with quads and bends to achieve momentum compaction (wiggler) –Magnet aperture ~ 40cm Total Length ~1100 m (incl. matching and beam extraction lines) Minimum design is possible if assume compression 6  0.3 mm only Shorter 2-stage BC Or short single-stage BC Cheaper magnets RF system BC1: 3 CMs with quads/each (+spare kly) BC2: 14 RFunits (3CM’s each)+1spare Total 48 CM’s per side One wiggler cell RF1 RF2 Wiggler 1 Wiggler 2

20. N.Solyak, RTML Overview BTW review, DESY, Oct. 24-27, 2011 20 RTML changes in Minimum Machine Configuration The RTML two-stage Bunch Compressor (top) and a possible short single-stage compressor (bottom). Lengths compared for 15 GeV. ~300 m G=31 MV/m Phase = -5 deg 14+1 RF Units (45CMs) 14 RF Units (42 CMs) 4.6 GeV Main Linac Single-stage BC is possible, if not support flexibility of parameter set Changes from RDR: 9(6)mm  0.3(0.2)mm to 6mm  0.3mm (x20 co mpression )  Reduction in beamline and associated tunnel length by an equivalent of ~200-250 m (including some in SCRF linac)  Removal of the second 220 kW dump and dump line components  Remove one of the diagnostics sections (lower energy) 12 RF (36 CMs) 2 RF 1 RF

21. N.Solyak, RTML Overview BTW review, DESY, Oct. 24-27, 2011 21 Single-Stage BC Lattice Compression: - 6 mm → 0.3 mm Total length = 350 m - RF Section ( 6 CM’s ) - Wiggler (6-cell) - Diagnostics - Extr to Dump, DL - Matching to ML Pre-Linac: 4.4 GeV  15 GeV

22. Components(BC1+BC2) vs. (BC1S+preLinac) BC1+BC2BC1S+preLinac Length [m]1114800 RF units/klystrons1614 Cryomodules4842 Cavities414360 Bends204102 Quadrupoles8861 BPMs8459 BC1 InstrumentationBC2 Instrumentation (BC1S) phase monitor, bunch length monitor, LOLA profile monitor phase monitor, bunch length minitor, LOLA profile monitor 4 laser wires *No extraction to Dump (15 GeV) Per one RTML N.Solyak, RTML Overview 22 BTW review, DESY, Oct. 24-27, 2011

23. Higher compression in BC1S N.Solyak, RTML Overview BTW review, DESY, Oct. 24-27, 2011 23 Minimum achievable bunch-length in BC1S Increase R 56 and minimization of T 566 Compensation of non-linearity Sextupoles Using 3rh harmonic cavities in CM (3.9 GHz) * (STD = standard BC1S) Compression 6  0.15mm required for 1TeV upgrade can be achieved in Two-stage compressor, not in BC1S.

24. Redesign of the Extraction Line after BC1S Study of several possible designs of Extraction Lines Option with Strong collimation Option with No collimation Sextupoles No collimationStrong collimation 24 N.Solyak, RTML Overview BTW review, DESY, Oct. 24-27, 2011

25. N.Solyak, RTML Overview BTW review, DESY, Oct. 24-27, 2011 25 Estimated Cost impact (G.Dugan) CFS: reduction of tunnels: –~300 m of regular tunnel –No service tunnel –No alcoves for 2 extraction lines and dumps (radiation area) –Possible more saving in tunnel in central area Cost reduction due to reduction of hardware components (~??? M$) –12 CMs –4 klystrons/modulator/PDS –2 extraction lines with 2 beam dumps –Number of Magnets, fast kickers, septums, PS –Diagnostics:, BPMs, Laser wires, etc.. –Vacuum components

26. N.Solyak, RTML Overview BTW review, DESY, Oct. 24-27, 2011 26 Emittance Growth in RTML Region BBA methodDispersive or chromatic mean emittance growth Coupling mean emittance growth Return LineKM and FF to remove beam jitter 0.15 nm 2 nm (with correction) Turn around Spin rotator KM and Skew coupling correction 1.52 nm (mostly chromatic) 0.4 nm (after correction) Bunch Compressor KM or DFS and Dispersion bumps >5 nm (KM+bumps) 2.7 nm (DFS+bumps) 0.6 nm (w/o correction) Total~5 nm almost all from BC3nm (w/o complete correction) Shown rms numbers Effect of coupler RF kick & wakes is not included Dynamic effects are not included Emittance growth is large (pre-RDR budget 4nm, need ~10nm) Summary of Studies for RDR (LET meeting, Dec.2007 SLAC)

27. N.Solyak, RTML Overview BTW review, DESY, Oct. 24-27, 2011 27 Emittance Growth in Bunch Compressors Emittance growth due to misalignments and couplers seems to compensated both for BS1S and BC1+BC2 Girder pitch optimization is very effective to counteract coupler kicks, both for BS1S and BC1+BC2 In BC1S, Crab Cavity seems to be similar effective, but it would require a new hardware and slight redesign of the cryomoodule A.Latina, TILC09 2.3 nm (over 100 machines)

28. Emittance growth in entire RTML (w/o BC1S) N.Solyak, RTML Overview BTW review, DESY, Oct. 24-27, 2011 28 Vertical Emittance growth (average) and Histogram for 1000 seeds

29. N.Solyak, RTML Overview BTW review, DESY, Oct. 24-27, 2011 29 Stray magnetic fields RTML requirement for high frequency stray magnetic fields: B 1Hz (K.Kubo, 2006) Magnetic field examples –Commercial SC solenoid – 10 Tesla (1 e+1) –Earth magnetic field – 50 micro-Tesla (5 e-5) –Cell phone– 100 nano-Tesla (1 e-7) –Beating human heart – ~ 10 pico-Tesla (1 e-11) Frequency dependence –< 0.1 Hz (can be compensated by control system) –> 100 kHz (attenuated in the structure) Classification (following F.R.T.) –60 Hz and its harmonics (near-coherent with 5-Hz pulsing) –Fields from RF systems (coherent with 5-Hz pulsing) –Others (non-RF technical sources) (uncorrelated with pulses) Previous work - “Sensitivity to Nano-Tesla Scale Stray Magnetic Fields”, SLAC LCC Note-0140 (June 7, 2004)  Data from SLC End station B. Conclusion (for NLC): we are mostly OK - DESY (TESLA TDR study)

30. N.Solyak, RTML Overview BTW review, DESY, Oct. 24-27, 2011 30 Magnetic Stray Fields Studies Hardware: 3-axis fluxgate magnetometer 0.1mT full scale DC to 3 kHz 20 pT/sqrt(Hz) Measurement: Near klystron In shielded cave (20m from kly) Klystron On/Off Fermilab A0 experimental area with cryogenic and 5 MW klystron/modulator RTML requirement for stray fields in Return Line 1Hz) SLAC measurements (at Station A) are promising (~2nT) Need more studies for different sites. Stability of 60Hz is an issue

31. N.Solyak, RTML Overview BTW review, DESY, Oct. 24-27, 2011 31 Total integrated field ~9 nT ( >1Hz ) Only 60/180/300 Hz peaks are removed 15, 30 and 45 Hz (Linac & Booster) ~ 5nT Other harmonics 120/180 /240Hz)~ 2nT All the rest ~ 2 nT Spectrogram and Integrated spectrum 5MW Klystron Modulator Transformer Cryogenic Pumps Power Supplies Tevatron shaft Etc… Stray magnetic fields measurements at A0: A0 - Noisy place More details in D.Sergatskov talk, ALCWS, 2009. Mu-metal shielding will help to reduce fields !

32. RF stability requirements for BC and ML phase tolerance (deg) amplitude tolerance (%) correlated BC phase errors0.240.35 uncorrelated BC phase errors0.440.58 uncorrelated BC amplitude errors1.62.7 correlated linac phase errorslarge0.35 uncorrelated linac phase errorslarge6.6 uncorrelated linac amplitude errorslarge0.86 Table 1: Summary of tolerances for phase and amplitude control. These tolerances limit the average luminosity loss to <2% (120 μm IP shift per beam) and limit the increase in RMS center-of-mass energy spread to <10%. Correlated phase errors – klystrons error is the same distr. gaussian from pulse-to-pulse. Uncorrelated phase errors – klystrons uncorrelated phase errors, distributed gaussian. Uncorrelated amplitude errors –klystrons uncorrelated amplitude errors, distr. gaussian N.Solyak, RTML Overview 32 BTW review, DESY, Oct. 24-27, 2011 Note: calculations done for pre-RDR lattice (ILC-2005 ), see M.Church, FNAL, 2006.

33. Phase stability in ILC Bunch Compressors Jitter in bunch position vs. phase jitter for correlated errors (RDR two-stage BC (green) and BS2009 single-stage BC (red) correlated errors : ∆ φ ~ 0.16 ° /0.24 ° /0.32 ° – SB2009/ pre-RDR / RDR uncorrelated errors : ∆ φ ~ 0.40 ° /0.44 ° /0.6 ° – SB2009/ pre-RDR / RDR N.Solyak, RTML Overview 33 BTW review, DESY, Oct. 24-27, 2011 Andrea Latina, Fermilab, 2010

34. 34 ILC bunch compressor (SB2009): Bunch compressor has tighter tolerances for RF phase and amplitude stability than the Main Linac. For 6mm  0.3 mm compression: Phase stability tolerance: ~0.16° rms at 1.3 GHz - The tolerance is on jitter between electron and positron sides. Amplitude stability tolerance: ~0.25% rms Bunch compressor rf cavities operate close to zero-crossing: -(105 ÷ 120)  off-crest (BC1S), -(20 ÷ 40)  for (BC2) Gradient: ~ 25-27 MeV/m N.Solyak, RTML Overview BTW review, DESY, Oct. 24-27, 2011

35. Two possible FLASH Experiment schematics. One way is to measure bunch arrival time using Bunch Arrival Monitors(BAM) and remove its contribution from the measured jitter. Only one RF unit is required. Other way is to use two RF units operating at zero-crossing but 180 deg with respect to each other. This configuration leads to relaxed requirements for the bunch arrival stability and prevents increasing correlated energy spread. In order to make precise measurements of the amplitude and phase stability at FLASH, the bunch arrival jitter caused by the laser, RF gun and pre-accelerator and BC should be minimized or excluded. N.Solyak, RTML Overview BTW review, DESY, Oct. 24-27, 2011 35 315 m Bunch Compressor Bypass Undulators sFLASH Bunch Compressor 5 MeV160 MeV500 MeV1200 MeV Acc.Cavities Diagnostics FEL Experiments

36. BTW review, DESY, Oct. 24-27, 2011 36 Two RF systems RF 1 RF 2 N.Solyak, RTML Overview Schematic of the bunch jitter compensation. The two RF modules RF1 and RF2 are operating in counter-phase near the zero crossing. ACC45 ACC67 Allows to evaluate two systems with respect to each other – just like we need for the electron and positron BC’s If two RF systems are running at equal amplitudes and 180  apart, the correlated energy spread and bunch arrival jitter are mostly canceled The phase jitter of one system with respect to another will show up as energy jitter in the beam.

37. FLASH RF jitter analysis (Run Feb.8,2011) VS phase/amplitude stability (Run Feb.8 2011) intra-train pulse-to-pulse (factor) –Gun : 0.7  & 1.4% (pkpk) x (1.1) x 1.1 (meas.errors ?) –ACC39: 0.05  & 0.1% (pkpk) x (3 ) x (2) –ACC1: 0.05  & 0.04%(pkpk) x (1.2) x (2) (stable in phase) –ACC23: <0.15  & 0.06% (pkpk) x (3) x (2) (more noisy) –ACC45: <0.15  & 0.06% (pkpk) x (3) x (3) (more noisy) –ACC67: <0.15  & 0.06% (pkpk) x (2.5) x (1.2) (stable in ampl.) ACC45 and ACC67 VS typical total jitter (peak-to-peak) –in phase < 0.15  ; in amplitude ~ 0.06 % –Train by train jitter is x3 larger RMS jitter is lower (~1/sqrt(3)) Final energy jitter is ~0.05% N.Solyak, RTML Overview BTW review, DESY, Oct. 24-27, 2011 37

38. BTW review, DESY, Oct. 24-27, 2011 38 Summary of proposal to study RF stability ILC bunch compressor has stringent requirement for the RF amplitude and phase stability: –0.25% and ~0.16° rms at 1.3 GHz –Beam off-crest, close to zero-crossing ( not typical for LLRF) FLASH provide good opportunity to test required stability For a single RF unit: –Beam energy ~ 700 MeV –Required short bunch length <1mm. –Require precise measurements of bunch arrival time (<100 fs  0.05  ) –Possible to run beam not at zero-crossing For two RF units (preferable): –Beam energy 400 ÷ 500 MeV –Two rf units ACC45 & ACC67 powered by 2 klystrons –Same energy gain per RF unit –Does not require precise bunch arrival time measurements. –Not sensitive to the bunch length (cancel out) Important: Cross-checking results vs. RF-off ( ACC67). Useful for calibration and statistics. N.Solyak, RTML Overview Long train operation workshop. DESY, June,2011

39. Vacuum requirements RTML vacuum system is fairly simple and straightforward, described in details in RTML website (PT). There are basically 4 main sub-regions to the system: Cryomodules: same specs as in ML Warm sections with strong focusing – ERTL, TURN,diagnostic region. –100 nTorr, no baking, no beam radiation –Engineering spreadsheet and technical note from Yusuke Suetsugu which covers the engineering of this chamber. Engineering spreadsheettechnical noteYusuke Suetsugu Warm sections with weak focusing ELRT (Return line): –20 nTorr, limited by beam-ion effects (study by Lanfa Wang)Lanfa Wang –20mm OD stainless steel, “passivation”, no baking –Costing of chambers done by John Noonan (spreadsheet)John Noonanspreadsheet BC1S wigglers: –100 nTorr, SS 20 mm OD chambers, unbaked. with base pressure. –Issue here is that the chambers are wider (up-to 40cm in BC2). However, I think that there is a standard 2 cm OD chamber for this area included in Suegutsu- san's spreadsheet.spreadsheet N.Solyak, RTML Overview BTW review, DESY, Oct. 24-27, 2011 39

40. Example of costing 15 km transport line N.Solyak, RTML Overview BTW review, DESY, Oct. 24-27, 2011 40 John NoonanJohn Noonan spreadsheetspreadsheet

41. N.Solyak, RTML Overview BTW review, DESY, Oct. 24-27, 2011 41 Re-visit of Vacuum system for RTML Return line Tight vacuum req. in Return Line (<10nTorr) - Passivated SS, ID=35mm, in magnet ID=16mm - 86 curved strings followed by 8 straight strings; - 1 bellow/1 quad magnet - If one string uses vacuum breaker, the next string uses gate valve. Final Report with Cost estimation (Xiao Qiong, IHEP/China) In

42. RTML Magnet Families N.Solyak, RTML Overview BTW review, DESY, Oct. 24-27, 2011 42

43. SB2009 Magnet count (updated) N.Solyak, RTML Overview BTW review, DESY, Oct. 24-27, 2011 43

44. Other technical systems so far. Beam Dumps and Stoppers: –2 (per side) high-power beam dumps, with 220 kW –Water cooled, 10atm, 2300 l/min., radiation nshielded enclosures. –3 low-power PPS stoppers (Personnel Protection System) in each RTM Collimators –20 adjustable jaw collimators with a rectangular aperture (RCOLs), x/y, 0.6 RL titanium "spoiler" and no water cooling, 220 W, half-gaps of 3.4 mm at the x collimators and 1 mm at the y. –28 fixed-aperture collimators with a cylindrical geometry (ECOL), –The dogleg collimators with half-gap of 0.98 mm; Cryomodules and Cavities (6 CM with 8C1Q configuration) –4 normal-conducting dipole-mode cavities (S/C-band“LOLA”) RF Sources (4 klystrons+4 short pulse klystrons for “LOLA”) A lot of Instrumentation (W.Manfred spreadsheet) –Beam Position Monitors (1,528 BPMs in the two RTMLs) C/S-band –Laser wire monitors, –Etc. N.Solyak, RTML Overview BTW review, DESY, Oct. 24-27, 2011 44 spreadsheet by T.Markiewicz for global dumps, stoppers, collimatorsT.Markiewiczglobal dumps, stoppers, collimators M.Wendt – for diagnostics

45. 10 Hz operation in eRTML (Low c.m. E option) Almost all room temperature components are working in CW regime, 5 or 10 Hz no difference –Exception: Fast-kickers in two extraction lines (used only for emergency beam abort). -Dump power still not exceed 220kW limit. RF system: 6 CM (2 RF units); E acc =26.8 MV/m –Cryogenic losses almost doubled (60-100 % depending on pulse length) for 10 Hz vs. 5Hz. –Klystron is designed for 10 Hz operation (XFEL specs) –Some concerns about LLRF, LFD compensation and microphonics, especially in case when RF pulse length and beam current will change from shot-to-shot. N.Solyak, RTML Overview 45 BTW review, DESY, Oct. 24-27, 2011

46. 1TeV upgrade Two-stage Bunch Compressor will work for obtaining short (150 micron) bunches required for 1 TeV N.Solyak, RTML Overview BTW review, DESY, Oct. 24-27, 2011 46

47. Summary / Conclusion Lattice design for SB2009 was completed. –Single-stage Bunch compressor. –Extraction to Dump Line after single-stage BC have been redesigned to accommodate larger energy spread (3.5% vs. 2.5% in RDR) –New RTML lattice was designed to accommodate proposed changes in accelerator layout in Central Area (DR, e+/e- sources, BDS) –Modifications of other lines to adjust geometry Performance of single-stage design is comparable with two-stage BC for compression from 6mm to 0.3 mm. Performances of the entire RTML have been evaluated, and resulted satisfactory. Budget for vertical emittance growth in RTML is ~8 nm. Reviewed Technical systems and count of hardware, CFS requirements and configuration of RML equipment in tunnels. At 10 Hz operation scenario (low CM energy), the required average RF power and cryogenic losses should be doubled. It is not an issue for 6 cryomodules in BC, powered by 2 separate klystrons (less than for ML). Other RTML systems are CW => not sensitive to rep.rate. N.Solyak, RTML Overview 47 BTW review, DESY, Oct. 24-27, 2011

48. RF parameters for 10 Hz operation ScenarioFull PowerLow Power10Hz - Low P RF configuration KCS & DRFSKCSDRFSKCSDRFS I_beam mA96.24.56.24.5 # bunches/train 26251312 # trains per second e+ Hz555 Max energy e+ GeV250 125 E acc (during beam pulse) MV/m31.5 15.75 Length of fill pulse ms0.5950.861.190.861.19 Length of beam pulse ms0.970.700.970.700.97 Fall time (exponential) ms0.861.241.721.241.72 # train per second e-: Hz555 Max energy e- GeV250 150 E acc (during beam pulse) MV/m31.5 18.9 Length of fill pulse ms0.5950.861.190.5170.714 Length of beam pulse ms0.970.700.970.700.97 Fall time (exponential) ms0.861.241.720.751.03 # trains per second e-: Hz 5 max energy e- GeV 125 E acc (during beam pulse) MV/m 15.75 Length of fill pulse ms 0.430.595 Length of beam pulse ms 0.700.97 Fall time (exponential) ms 0.620.859 N.Solyak, RTML Overview 48 BTW review, DESY, Oct. 24-27, 2011 For Main Linac Single- stage compressor..... Eacc 26.8 MV/m