Neutrino Town Meeting CERN – May 14-16, 2012 SPL R&D and Potential Applications R. Garoby for the SPL team* O. Brunner, S. Calatroni, O. Capatina, E. Ciapala, F. Gerigk, E. Montesinos, V. Parma, K.M. Schirm, + I. Aviles Santillana **, R. Bonomi **, J. Chambrillon, P. Coelho Azevedo**, K. Liao, N. Valverde Alonso** ** supported by ESS

HP-SPL: R&D Management

R. G. – 15/05/ R & D for a High Power SPL formally supported at CERN in view of multiple future potential applications  ~1.7 MCHF and 6 FTEs / year Collaboration with ESS  Fellows and procurement of klystron modulator for SM18 French in-kind contribution  Tuners, Helium tanks, use of Saclay 704 MHz high power test place… EC-supported programmes EuCARD (WP10)  Development and test of beta=1 (CEA) and beta=0.65 (IN2P3) 5 cells cavities CRISP (WP4)  Joint work with ESS and DESY  EC-supported manpower for upgrading and exploiting the SM18 test place LAGUNA-LBNO  EC-supported fellow for studying proton drivers at CERN using LP- or HP-SPL DOE-supported programme BNL  Development and test of a  =1 cavityResources  SPL documentation in EDMS [ ] SPL documentation  SPL meetings in Indico [ ] SPL meetingshttp://indico.cern.ch/categoryDisplay.py?categId=1893  SPL documentation in EDMS [ ] SPL documentation  SPL meetings in Indico [ ] SPL meetingshttp://indico.cern.ch/categoryDisplay.py?categId=1893

R. G. – 15/05/ Organization (at CERN) Guideline «Project-like» structure aimed at meeting the objectives of the HP-SPL R&D: Building and testing a prototype cryomodule with 4 cavities Updating CERN infrastructure and competence in superconducting RF technology Preparing submission of future subjects of R&D [design and construction of a full-size cryomodule, high power RF sources, HIPIMS (High Power Impulse Magnetron Sputtering)…] Work Units -Design, construction and test of the prototype cryomodule (Leader: V. Parma) -Components: Cryomodule, Cavities, RF items (Couplers, tuners, …), cryogenics equipment… -Assembly (with adequate tools): cavities string in clean room, inclusion in cryomodule -Tests: cavities in vertical cryostat, assembled cryomodule in bunker. -Upgrade of the SM18 infrastructure (Leader: O. Brunner) -HP water rinsing system and upgraded clean roon -Cryogenics for efficient operation at 2K -High power RF at 704 MHz (klystron, modulator, high power distribution) -Low Level RF and controls -SC RF cavities technology (Leader: E. Ciapala) -Fabrication and processing -Test, diagnostics and analysis

HP-SPL: Baseline Design Parameters

R. G. – 15/05/ Option 1Option 2 Energy (GeV)2.5 or 52.5 and 5 Beam power (MW) 2.25 MW (2.5 GeV) or 4.5 MW (5 GeV) 5 MW (2.5 GeV) and 4 MW (5 GeV) Protons/pulse (x )1.12 (2.5 GeV) + 1 (5 GeV) Av. Pulse current (mA)2040 Pulse duration (ms)0.91 (2.5 GeV) (5 GeV) 2  beam current  2  nb. of klystrons etc. Ion speciesH − Output Energy5GeV Bunch Frequency352.2MHz Repetition Rate50 Hz High speed chopper< 2 ns (rise & fall times) Required for muon production Required for flexibility and low loss in accumulator Required for low loss in accumulator HP-SPL: Beam Characteristics

R. G. – 15/05/ Medium  cryomodule High  cryomodules Ejection 9 x 6  =0.65 cavities 11 x 8  =1 cavities 13 x 8  =1 cavities to EURISOL Debunchers To HP-PS and/or Accumulator High  cryomodules From Linac4 0 m0.16 GeV110 m0.73 GeV291 m2.5 GeV500 m5 GeV Segmented cryogenics / separate cryo-line / room temperature quadrupoles: -Medium  (0.65) – 3 cavities / cryomodule -High  (1) – 8 cavities / cryomodule Low energy Intermediate energy High energy HP-SPL: Block Diagram

R. G. – 15/05/ Medium  cryomodule High  cryomodule Energy range: 160 MeV – 732 MeV 5 cell cavities Geometrical  : 0.65 Maximum energy gain: 19.4 MeV/m 54 cavities (9 cryomodules) Length of medium  section: ~ m Energy range: 732 MeV – 5 GeV 5 cell cavities Geometrical  : 1 Maximum energy gain: 25 MeV/m 192 cavities (24 cryomodules) Length of high  section: ~360 m Energy gain (MeV/m) Position (m) HP-SPL: Cavities & Cromodules

Status and Plans of R&D

R. G. – 15/05/ Cavities(1/4)

R. G. – 15/05/ Cavities(2/4)

R. G. – 15/05/ Cavities(3/4)

R. G. – 15/05/ Cavities(4/4)

R. G. – 15/05/ SPL coupler: requirements Technical Choices Single window coupler Fixed coupler With a Double Walled Tube Mounted in clean room with its double walled tube horizontally in only one operation Vertically below the cavity and will be a support for the cavity (first time worldwide) With a HV DC biasing capacitor Air cooled 14 RF Characteristics f0f MHz Power levels 1000 kW pulsed = 2.0 ms 50 Hz (20 ms) 100 kW average Cavity design gradient19-25 MV/m Q ext of input coupler1.2 x 10 6 Input line Ø 100 / 43.5 mm = 50 Ω (from the cavity design) WaveguidesWR 1150

R. G. – 15/05/ SPL coupler: 2 designs LHC-derived SPS-derived Doubled-wall tube Ceramic window Air cooling

R. G. – 15/05/ SPL coupler: test assembly Four ‘vacuum lines’: – 4 cylindrical window couplers – 4 planar disk window couplers – 8 Double walled Tubes – 4 test boxes DESY clean process assembly – (Jlab also proposed to help) CERN LLRF measurements CEA RF power tests – (BNL also proposed to help) 16

R. G. – 15/05/ Test box assembly not easy because of specific surfaces roughness needed for helicoflex Couplers assembly was also not easy because : – Couplers are heavy – Last connection has to be done manually – Ok for few prototypes, not for a large series SPL coupler: clean room assembly (DESY)

R. G. – 15/05/ Tests started with cylindrical window couplers Not baked out, static vacuum ~ 2 x mbar – Wanted to check RF – Size of the test box 250 mm x 600 mm – Helicoflex Pulse mode process Reached > 1MW – 25 Hz – 2 ms (limited by heating due to lack of Cu platting) SPL coupler: RF high power tests (CEA)

R. G. – 15/05/ System/Component/ActivityPerson(s) in chargeLab Cavities/He vessel/tuner constructionO.Brunner, O.Capatina, Th.Renaglia, F.Pillon, N.Valverde, M.Esposito, I.Aviles, G.Devanz CERN CEA-Saclay SRF, magnetic shielding, Clean-Room activities, RF test stations (SM18) E.Ciapala, T.Junginger, K.Shirm, J.Chambrillon, O.Brunner CERN RF CouplerE.Montesinos, G.Devanz CERN CEA Saclay Vacuum systemsG.VandoniCERN Cryogenics, (cryo infrastructure SM18)U.Wagner, (O.Pirotte)CERN Survey and alignmentP.BestmanCERN Cryo-module conceptual designR.Bonomi, D.Caparros, O.Capatina, P.Coelho, V.Parma,Th.Renaglia, A.Vande Craen, L.R.Williams CERN Cryo-module detailed design & Integration & Cryostat assembly tooling Ph.Dambre, P.Duthil, P.Duchesne, S.Rousselot, D.Reynet CNRS/IPNO-Orsay SPL Machine architectureF.GerigkCERN ESS Cryomodule developmentsCh.DarveESS, Lund Cryo-module Technical CoordinationV.ParmaCERN ESS/CERN Fellow Short cryomodule: the actors

R. G. – 15/05/ Short cryomodule: schematic layout Connection to cryo distribution line CW transition RF coupler, bottom left side Cavity additional support 1.7% Slope (adjustable 0-2%) Cryo fill line (Y), top left Technical Service Module End Module Phase sep. Inter-cavity support Now suppressed

R. G. – 15/05/ General concept and dimensions (not latest design) 7400 SSS Courtesy P.Duthil (IPNO) (views S.Rousselot, IPN-Orsay) Transport,dressing and alignment frame Short cryomodule: vacuum vessel

R. G. – 15/05/ K vapor generator reservoir (with elect.heater) standard support Last cavity IC support Ph.Separator pot DN80 gate valve (single valve) CWT 50 K heat intercept (views S.Rousselot, IPN-Orsay) Short cryomodule: technical service module Courtesy P.Duthil (IPNO)

R. G. – 15/05/ Courtesy W. 5th SPL collaboration Meeting D. Valuch LLRF under development

R. G. – 15/05/ Upgraded installation in SM18

R. G. – 15/05/ Delivery of 704 MHz klystron and modulator Preparation of SM18 infrastructure (cryogenics, RF, clean-room) Cavities production Cavities processing/RF testing RF couplers Clean room assembly of string Cryomodule (& assy tooling) design Cryomodule fabrication Cryomodule assembly Start cryomodule RF testing Short cryomodule: master schedule

R. G. – 15/05/ Related R & D Nb coating of Cu cavities, using the HIPIMS (High Power Impulse Magnetron Sputtering) technology – In collaboration with Sheffield Hallam University (UK). – Supported in the context of the construction of LHC spare cavities. – Potentially very attractive technology for the SPL (raw material cost, mechanical stiffness). – First results on low beta 704 MHz cavity: end 2012

SPL Applications to Proton Drivers

R. G. – 15/05/ Low Power SPL (LP-SPL)New High Power PS (30-50 GeV, 2MW beam power) using the Low Power SPL (LP-SPL) as injector. Feasibility Study based on the work for SPL and PS2 supported within the LAGUNA-LBNO DS. 50 GeV synchrotron-based proton driver Long baseline experiment (2300 km) CERN-Pyhasalmi (Finland)

R. G. – 15/05/ PS2 parameters: reminder… ParameterunitPS2PS Injection energy kineticGeV Extraction energy kineticGeV Circumferencem Max. bunch intensity LHC (25ns)ppb4.0 x x Max. pulse intensity LHC (25ns)ppp6.7 x x Max. pulse intensity FTppp1.0 x x Linear ramp rateT/s Repetition time (50 GeV)s~ /2.4 Max. stored energykJ80070 Max. effective beam powerkW

R. G. – 15/05/ PS2 integration at CERN: reminder 30PAC 2009 VancouverPS2 Design Optimization, M.Benedikt PS2 SPL Linac4 SPL to PS2 PS PS/LEIR to SPS / PS2 SPS PS2 to SPS –“Straight” H - inj. line SPL  PS2 avoiding large bending radii to minimise Lorentz stripping of H -. –Minimum length of inj. line TT10  PS2 for ions and protons from PS complex. –Minimum length HE line PS2  SPS.

R. G. – 15/05/ SPL-based 5 GeV – 4 MW proton drivers have been designed [SPL + 2 fixed energy rings (accumulator & compressor)] which meet these requirements References: – SPL based proton driver/ R. Garoby, talk at NuFact06, – Feasibility Study of Accumulator and Compressor for the 6-bunches SPL-based Proton Driver / M. Aiba, CERN-AB – A first analysis of 3-bunches and 1-bunch scenario for the SPL-based Proton Driver / M. Aiba, CERN-AB- Note BI – Beam Stability in the SPL Proton Driver Accumulator for a Neutrino Factory at CERN / E. Benedetto, to be published – SPL-based Proton Driver for a Neutrino Factory at CERN, M. Aiba, E. Benedetto, R. Garoby, M. Meddahi, poster nb.25 (this workshop) ParameterBasic valueRange Beam energy [GeV] Burst repetition rate [Hz]50? Number of bunches per burst (n)41 – 6 ? Total duration of the burst [  s] ~ Time interval between bunches [  s] (t int ) 16 ~ 50/(n-1) Bunch length [ns] Specifications (from ISS report) HP-SPL based proton driver: principle (1/2)

R. G. – 15/05/ Beam accumulation – Accumulator ring » Charge exchange injection » n x 100  s accumulation time » Isochronous (  =0): beam frozen longitudinally to preserve  p/p » No RF (=> minimum impedance) » 1-6 bunches of ~120 ns length 2.Bunch compression -Compressor ring » Large RF voltage (large stored energy & minimum RF power) (=> bunch rotation on stored energy) » Large slippage factor  => rapid phase rotation in few x10  s, » ~2ns rms bunch extraction to the target (=> moderate  Q because of dispersion) 3.Synchronization between rings -Ratio of circumferences guaranteeing correct positioning of successive bunches inside the compressor without energy change in any ring HP-SPL based proton driver: principle (2/2)

R. G. – 15/05/ Accumulation Duration = 400  s Compression t = 0  s t = 12  s t = 24  s t = 36  s etc. until t = 96  s Accumulator [120 ns pulses - 60 ns gaps] SPL beam [42 bunches - 21 gaps] Compressor [120 ns bunch - V(h=3) = 4 MV] Target [2 ns bunches – 6 times] Generation of 6 bunches

R. G. – 15/05/ from M. Aiba Bunch rotation before ejection

R. G. – 15/05/ from M. Aiba Main parameters

R. G. – 15/05/ Beam delivery on 4 targets & horns Principle: Use of 2 bipolar kickers (or bipolar pulsed magnets): ± 45˚ rotation wrt the z axis K1 (K2) deflects to D1 and D3 (D2 and D4) Need of 1 compensating dipole per beam line (1 angle for each target): Apply a symmetry in the system Angle of deflection (rad) Kinetic energy (GeV) Magnetic length (m) Magnetic field (T) 2000mm T1 T2 T4 T3 z 3D view side view E. Bouquerel – IPHC, EUROnu meeting, March 27, 2012 >>KEY PARAMETER<<

Summary

R. G. – 15/05/ Technology (1/2) Presently, the HP-SPL R&D: progresses at a good pace, leading to the high power test of a short 4 cavities cryomodule in allows testing the validity of new concepts that should result in significant savings (RF couplers, SS He tanks, Cryomodule design…) can potentially be used in multiple projects at CERN as well as outside (ESS, MYRRHA) and benefits from external support (ESS and EU programmes) is a means for CERN to embed inside the network of labs involved in superconducting RF technology (CEA, IN2P3, DESY, JLAB, FNAL, ANL…) and re-establish in-house competence in that field at the state-of-the-art level drives infrastructural upgrades (e.g. electro-polishing facility, clean room, high power RF at 704 MHz…) which will be beneficial for other development (LHC main RF, Crab cavities, HIE IDOLDE…)

R. G. – 15/05/ Technology (2/2) Important future R&D subjects HOM damper for beam stability at high current Cavities in view of reaching the expected performance/simplifying fabrication/evaluating alternative solutions (Nb on Cu) Cryomodule towards a full size prototype RF amplifiers for reducing cost Power supply for high power amplifier for reducing cost

R. G. – 15/05/ Accelerator design The SPL accelerator design is «mature» and stable In the context of the LAGUNA-LBNO: – The LP-SPL design will be adapted to the requirements of the HP-PS – The HP-SPL design will be briefly revisited and completed with the design of the accumulation ring Other applications may require resuming/refining accelerator design: – e+/e- acceleration in the ERL of the Linac-Ring option of LHeC – LEP-3 – LP-SPL remains a back-up option for the LHC injector complex…