The ILC Accelerator Complex

Transcription

1 The ILC Accelerator Complex Nick Walker DESY/GDE UK LC meeting 3 rd September 2013 Oxford University, UK. 1

2 ILC in a Nutshell GeV E cm e + e - collider L ~ cm -2 s -1 upgrade: ~1 TeV central region SCRF Technology 1.3GHz SCRF with 31.5 MV/m 17,000 cavities 1,700 cryomodules 2 11 km linacs Developed as a truly global collaboration Global Design Effort GDE ~130 institutes 2

3 500 GeV Parameters Physics Beam (interaction point) Beam (time structure) Max. E cm 500 GeV Luminosity cm -2 s -1 Polarisation (e-/e+) 80% / 30% d BS 4.5% s x / s y 574 nm / 6 nm s z 300 mm ge x / ge y 10 mm / 35 nm b x / b y 11 mm / 0.48 mm bunch charge Number of bunches / pulse 1312 Bunch spacing 554 ns Pulse current 5.8 ma Beam pulse length 727 ms Pulse repetition rate 5 Hz Accelerator (general) Average beam power Total AC power (linacs AC power 10.5 MW (total) 163 MW 107 MW) 4

4 1.3 GHz Superconducting RF Cavity solid niobium standing wave 9 cells operated at 2K (LHe) 35 MV/m Q

5 Cryomodule construction 11

6 Worldwide Cryomodule Development CM1 at FNAL NML module test facility S1 Global at KEK SRF Test Facility (STF) PXFEL 1 installed at FLASH, DESY, Hamburg now commencing XFEL production 6

7 KEK (2011) S1 G 7

8 European DESY Largest deployment of this technology to date cryomodules cavities GeV The ultimate integrated systems test for ILC. 8

9 Quest for high gradients # cavities GDE worldwide R&D effort to establish high-gradient cavity production 6 Now qualified cavity vendors % XFEL (mass) production large (~800) unbiased statistical sample (<10% ) critical for ILC MV/m 1st & 2nd pass 1st pass yield 1st+2nd pass yield 1st pass 35 MV/m 90% 80% 70% 60% 50% 40% yield ILC-HiGrade programme % 20% 2 10% MV/m 9 0%

10 Worldwide Cryomodule Development PXFEL 1 installed at FLASH, DESY, Hamburg 15

11 9mA Experiment XFEL ILC (upg.) FLASH design 9mA studies Bunch charge nc # bunches * 2400 Pulse length ms Current ma Many basic demonstrations: - heavy beam loading with long bunch trains - operation close to quench limits - klystron overhead etc. Development (LLRF & controls): - tuning algorithms - automation - quench protection etc. 11

12 RF Power Generation accelerator cryomodules shield wall 12

13 shield wall removed 13

14 Beyond the SCRF Main Linacs not too scale - injectors (sources and damping rings) - final focus system and interaction region 18

15 Central Region Central Region 5.6 km region around IR Systems: electron source positron source beam delivery system RTML (return line) IR (detector hall) damping rings Complex and crowded area common tunnel Damping Rings detector RTML return line e+ source e+ main beam dump e- BDS muon shild e- BDS 19

16 Damping Rings Circumference 3.2 km Energy 5 GeV RF frequency 650 MHz Beam current 390 ma Store time 200 (100) ms Trans. damping time 24 (13) ms Extracted emittance x 5.5 mm (normalised) y 20 nm No. cavities 10 (12) Total voltage 14 (22) MV RF power / coupler 176 (272) kw Positron ring (upgrade) Electron ring (baseline) Positron ring (baseline) No.wiggler magnets 54 Total length wiggler 113 m Wiggler field 1.5 (2.2) T Beam power 1.76 (2.38) MW Values in () are for 10-Hz mode (a) Arc quadrupole section (b) Dipole section Many similarities to modern 3 rd -generation light sources 20

17 Positron Source (central region) to Damping Ring not to scale! GeV e- beam aux. source (500 MeV) Photon collimator (pol. upgrade) Target Flux concentrator Pre-accelerator ( MeV) SCRF booster (0.4-5 GeV) Energy comp. RF spin rotation solenoid SC helical undulator located at exit of electron Main Linac 147m SC helical undulator driven by primary electron beam ( GeV) produces ~30 MeV photons Capture RF (125 MeV) converted in thin target into e+e- pairs e- dump photon dump GeV e- beam to BDS yield = 1.5 polarisation yield e+/e- 23

18 Alternative electron-driven source T. Omori et al, Nucl. Instrum. Meth. A 672 (2012)

19 Beam Delivery System and MDI Geometry ready for TeV upgrade e+ source e- BDS electron Beam Delivery System 24

20 IR region (Final Doublet) FD arrangement for push pull different L* ILD 4.5m, SiD 3.5m Short FD for low E cm Reduced b x * increased collimation depth universal FD avoid the need to exchange FD conceptual - requires study Many integration issues remain requires engineering studies beyond TDR No apparent show stoppers BNL prototype of self shielded quad 25

21 MDI (Detector Hall) Japanese detector hall concept 26

22 50 m ATF2 Final Focus R&D: KEK The ATF2 has been designed, constructed and operated under the international collaboration. Focal Point (ATF2-IP) y~37nm Final Focus (FF) System Extraction beamline Damping Ring y~10pm ATF2 LINAC DR 120 m ATF2 Technical Review, April3-4, 2013, KEK 4 Formal international collaboration 27

23 Final Focus R&D: KEK Test bed for ILC final focus optics - strong focusing and tuning (37 nm) - beam-based alignment - stabilisation and vibration (fast feedback) - instrumentation IP beam size monitor 28

24 Beyond the Baseline

25 Luminosity Upgrade Concept: increase n b from Reduce linac bunch spacing 554 ns 336 ns Increase current 5.8 ma 8.8 ma Doubles beam power 2 L = cm -2 s -1 AC power: 163 MW 204 MW (est.) shorter fill time and longer beam pulse results in higher RF-beam efficiency (44% 61%) 29

26 Luminosity Upgrade Adding klystrons (and modulators) Luminosity Baseline upgrade cavity RF unit K K Damping Ring: Luminosity upgrade 26 cavity RF unit K K Positron ring (upgrade) Electron ring (baseline) Positron ring (baseline) (a) Arc quadrupole section (b) Dipole section 30

27 Energy (TeV) upgrade e+ src e+ src e+ src e+ src start civil construction 500GeV operations civil construction + installation BC Main Linac 500GeV operations BDS IP BC Main Linac BDS IP Installation/upgrade shutdown BC final installation/connection removal/relocation of BC Removal of turnaround etc. Main Linac Installation of addition magnets etc. Commissioning / operation at 1TeV BDS IP BC Main Linac BDS 31

28 TeV Parameters (2 sets) Beam energy GeV 500 Collision rate Hz Number of bunches Bunch population P AC constrained 300 MW Bunch separation Pulse current ns ma RMS bunch length mm Electron RMS energy spread Positron RMS energy spread Electron polarisation % 80 Positron polarisation % 30 shorter bunch length (within BC range) Horizontal emittance Vertical emittance mm nm IP horizontal beta function mm IP vertical beta function mm 0.25 IP RMS horizontal beam size nm IP RMS veritcal beam size nm 2.8 horizontal focusing main difference Luminosity cm -2 s Fraction of luminosity in top 1% Average energy loss Number of pairs per bunch crossing Total pair energy per bunch crossing TeV low and high beamstrahlung 32

29 1.1 km bunch comp. 250 GeV staged LHF 1.3 km e+ src 15.4 km 5.1 km 2.2 km Main Linac BDS IP 125 GeV transport central region Half the linacs Full-length BDS tunnel & vacuum (TeV) ½ BDS magnets (instrumentation, CF etc) 5km 125 GeV transport line quasi-adiabatic energy upgrade? 33

30 TDR Value Estimate 7.8 Billion ILCU 22.6 Million person-hours 34

31 TDR Value Estimate By accelerator system BDS 4% IR 2% Common 7% Electron Source 3% Positron Source 4% Damping Rings 6% 7.8 Billion ILCU 22.6 Million person-hours RTML 8% Controls and Compu ng Infrastructrure 6% Instrumenta on 1% Dumps and Collimators 1% Vacuum 1% Non L-band RF 1% Area system specific 1% Main Linac 66% Magnets and Power Supplies 6% Installa on 1% Cryogenics 8% CFS-Civil construc on 18% CFS-other 11% CFS-Civil construction 10% CFS-other 6% L-band Cavities and Cryomodules 32% L-band HLRF 9% Cryogenics 7% Controls 2% TOTAL Main Linac 66% L-band HLRF 10% L-band Cavi es and Cryomodules 35% By technical system 34

32 Example Construction Schedule 35

33 GDE Timeline LHC physics Reference Design Report (RDR) Tech. Design Phase (TDP) 1 GDE LCC TDP 2 TDR published ~250 FTE per year (avg) ~2,000 MY ( ~5,000 if pre-gde included) ~300 M$ globally Global Event June 12 Tokyo CERN Fermilab 35

34 Linear Collider Collaboration ICFA Program'Advisory' Commi4 ee Linear'Collider'Board FALC Regional'Directors Brian'Foster Harry'Weerts Directorate' Lyn'Evans Deputy'(Physics)'' Hitoshi'Murayama ILC' 'Mike'Harrison CLIC' Steinar'Stapnes Physics'&'Detectors' Hitoshi'Yamamoto 36

35 Looking towards the East 36

36 Challenges of a mountainous terrain TDR: Japanese site-dependent design Long horizontal access tunnels ( 1 km) Almost entirely under ground installation Site-dependent design study will officially start now that Japanese candidate site has been announced ( ) 38

37 A European (in-kind) contributions to the ILC machine? > Cavity & Cryomodule production infrastructure > XFEL wisdom and know-how (including operations) > Large cryogenics systems (XFEL and LHC) > International project management experience (LHC, XFEL ) XFEL cold-linac consortium CERN LHC experience CERN, DESY Project tools (ILC-EDMS and beyond) > Other (machine) areas Damping rings Beam delivery system Sources CERN, DESY, UK, Frascati, LAL Strong synergy with CLIC

38 A European (in-kind) contributions to the ILC machine? > Cavity & Cryomodule production infrastructure > XFEL wisdom and know-how (including operations) > Large cryogenics systems (XFEL and LHC) > International project management experience (LHC, XFEL ) XFEL cold-linac consortium CERN LHC experience CERN, DESY Project tools (ILC-EDMS and beyond) > Other (machine) areas Damping rings Beam delivery system Sources CERN, DESY, UK, Frascati, LAL Strong synergy with CLIC

39 Summary GDE has completed its mandate And the R&D programme Design is ready to go Next steps: focus on site-dependent design for Kitakami site Under new management (LCC) Beginning to put together international team European XFEL is showing the way Europe is in a unique position to contribute to this ambitious project Worldwide funding situation needs work Waiting for strong signals from Japan European strategy and now US Snowmass process have opened the door for negotiations. 41