Status of CERN Injectors Upgrades

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Status of CERN Injectors Upgrades Introduction Status of linac developments Outcome of the HIP working group SPSC recommendations Consequences for Radio-active Ion Beams Final word R. Garoby ISOLDE Upgrade Standing Group November 16, 2004

INTRODUCTION R.G. 2 16/11/2004

Context & References SPL Study B. Autin, E. Benedico Mora, A. Blondel, K. Bongardt (KFZ Juelich), O. Brunner, L. Bruno, F. Caspers, E. Cennini, E. Chiaveri, S. Claudet, H. Frischholz, R. Garoby, F. Gerigk (RAL), K. Hanke, H. Haseroth, C. Hill, I. Hoffman (GSI), J. Inigo-Golfin, M. Jimenez, M. Hori (Tokyo Univ.), D. Kuchler, M. Lindroos, A. Lombardi, R. Losito, R. Nunes, M. Magistris, A. Millich, T. Otto, M. Paoluzzi, J. Pedersen, M. Poehler, H. Ravn, A. Rohlev, C. Rossi, R.D. Ryne (LANL), M. Sanmarti, E. Sargsyan, H. Schönauer, M. Silari, T. Steiner, J. Tuckmantel, D. Valuch, H. Vinckle, A. Vital, M. Vretenar HIP working group M. Benedikt, K. Cornelis, R. Garoby, E. Metral, F. Ruggiero, M. Vretenar Present characteristics (Conceptual Design Report 1): are optimized for a neutrino factory assume the use of LEP cavities & klystrons up to the highest energy Update is planned (CDR 2): based on updated physics requests using 704 MHz RF and bulk Niobium cavities in collaboration with CEA-Saclay & INFN- Milano to be published in mid-2005 Up-to-date information is available: on the CERN EDMS on the SPL site: http://psdiv.web.cern.ch/ps-div/spl_sg/ R.G. 3 16/11/2004

Collaborations (1/3) RFQ (IPHI) Injecteur de Protons de Haute Intensité (in French) IPHI - CERN collaboration Collaboration between CEA-Saclay / IN2P3 / CERN Goal: Build a 3 MeV RFQ to be tested in CW with 100 ma beam current at Saclay in 2006 and delivered at CERN in 2007 for the 3 MeV test place (pre-injector of the future linac 4 & SPL) First 1 m section R.G. 4 16/11/2004

High Intensity Protons Pulsed Injectors Collaborations (2/3) Joint Research Activity supported by the European Union in the 6 th Framework programme Main Objectives Means inside R&D of the technology for high intensity pulsed proton linear accelerators up to an energy of 200 MeV Improvement of existing facilities (E.U. request) at GSI, RAL and CERN 9 laboratories: RAL, CEA (Saclay), CERN, FZJ, GSI, Frankfurt University, INFN-Milano, IPN (Orsay), LPSC (Grenoble). 11.1 MEuros + 3.6 MEuros (E.U.) over 5 years (2004 2008) Organization 5 Work Packages WP1 : Management & Coordination (R. Garoby CERN) WP2 : Normal Conducting structures (J.M. Deconto LPSC Grenoble) WP3 : Superconducting structures (S. Chel CEA Saclay) WP4 : Beam chopper (A. Lombardi CERN) WP5 : Beam dynamics (I. Hoffmann GSI) R.G. 5 16/11/2004

INTERNATIONAL SCIENCE & TECHNOLOGY CENTER Common features: Collaborations (3/3) ISTC projects for Linac 4 & SPL - One institute competent in accelerators + one nuclear city - 2 years duration - Design and construction of a prototype for high power tests at CERN #2875 BINP (Novossibirsk) + VNIITF (Snezinsk) Subject: Coupled Cavity Drift Tube Linac (CCDTL) structure (40-100 MeV) + cold model of SCL structure (100-200 MeV) Cost: k$ 550 (10805 man.days) Status: active since October 2003 Prototype delivery: end 2005 #2888 ITEP (Moscow) + VNIIEF (Sarov) Subject: Drift Tube Linac (DTL) structure with magnetic focusing ( Alvarez ) (3-40 MeV) Cost: k$ 498 (? Man.days) Status: active since April 2004 Prototype delivery: summer 2006 #2889 - IHEP (Protvino)+ VNIIEF (Sarov) Subject: DTL structure with focusing by RF quadrupoles (DTL-RFQ) (3-40 MeV) Cost: k$ 500 (8399 man.days) Status: active since April 2004 Prototype delivery: summer 2006 R.G. 6 16/11/2004

New Resources 1) From CERN: DG s decision to allocate the resources missing for the completion of the E.U. supported activities. Result for HIPPI: Staff (effective ~ mid-2005) Material (effective January 2005) BDI CO PO RF Engineer 1 + 50 kchf/year (=> 400 kchf/year) Technicians 1 1 1 2 2) From outside (more collaborations ): INDIA: 2 visiting scientists in 2004. Letters exchanged at the DG level. Agreement in negotiation proposing Indian support for controls software, operation of the 3 MeV test place and delivery of klystron power supply. CHINA: Preliminary contacts at the highest level. Workshop in China next year to clearly establish the content of the agreement. Present proposal that China delivers the quadrupoles for the CCDTL section (40 to 90 MeV) of Linac4. R.G. 7 16/11/2004

STATUS OF LINAC DEVELOPMENTS R.G. 8 16/11/2004

Linac 4 parameters PHASE 1 (PSB) PHASE 2 (SPL) Beam energy 160 MeV Maximum repetition rate 2 50 Hz Source current 50 60 ma RFQ current 40 50 ma Chopper beam-on factor 75 62 % Current after chopper 30 30 ma Maximum pulse length 0.5 2 ms Average current 15 3000 µa Maximum beam duty cycle 0.1 10 % Transverse emittances (norm.) 0.33 π mm mrad Longitudinal emittance 0.24 π deg MeV R.G. 9 16/11/2004

Linac 4 layout (1) 95keV 3MeV 40MeV 90MeV 160MeV H- RFQ MEBT DTL CCDTL SCL IPHI RFQ 6 m 1 klystron 30 ma, 0.1% duty chopping line 3.6 m Drift Tube Linac 352 MHz 16.7 m 3 tanks 5 klystrons Cell-Coupled Drift Tube L. 352 MHz 30.1 m 33 tanks 6 klystrons Side Coupled Linac 704 MHz 28.1 m 20 tanks 5 klystrons Final Energy 160 MeV, factor 2 in βγ 2 w.r.t. present 50 MeV Linac2 Total Linac4: 86.5 m, 17 klystrons R.G. 10 16/11/2004

Linac 4 layout (2) 5 + + +, 6, 6 4. 3 5 7 4 + - 3 MeV Test Place R.G. 11 16/11/2004

Progress towards Linac4 (1/3) Operation with beam : end 2007 Beam dynamics studies at low energy. Demonstration of the chopper line capability to: generate the required time structure of the beam clean the beam from halo match the beam to the subsequent RF structures. 3 MeV Test Place: objectives R.G. 12 16/11/2004

Progress towards Linac4 (2/3) 3 MeV Test Place: components Chopper structure H - ECR ion source IPHI RFQ Bunching cavities Beam Shape and Halo Monitor H - beam HV switch unit Pulser Computer Water cooler x2 channels X-axis translator HV pulsed power supplies for the LEP klystrons R.G. 13 16/11/2004

Progress towards Linac4 (3/3) Development of Normal Conducting accelerating structures 3 40 MeV: - DTL (with CEA/IN2P3 and ITEP/VNIIEF): construction of a prototype Tank1 with dummy drift tubes + complete drift tube prototype (2006) - or DTL-RFQ: high power prototype to be designed and built by IHEP/VNIIEF (2006) 40 90 MeV: - CCDTL full power one-cell prototype built at CERN (end 2003). Multi-cell prototype to be built at BINP/VNIITF (2006) cooling channels (green) drift tube stem (fixed) Diameter ~500 mm Length ~ 800 mm pick-up port Material: Cu-plated stainless steel fixed tuner port cover supports coupling cell Assembling: EB weldings, Helicoflex joints waveguide port machining and welding at CERN workshop finished (15.11.03) to be tested with power in early summer 2004 90 160 MeV: - SCL:low power prototypes to be developed jointly by IN2P3 (Grenoble) and BINP/VNIITF R.G. 14 16/11/2004

OUTCOME OF THE HIGH INTENSITY PROTONS WORKING GROUP R.G. 15 16/11/2004

Identified users requests 1 USER CERN COMMITMENT Short term USERS WISHES Medium term Long term [ ~ asap!] [beyond 2014] LHC Planned beams Ultimate luminosity Luminosity upgrades FT (COMPASS) 4.3â10 5 spills/y? 7.2â10 5 spills/y CNGS 4.5â10 19 p/year Upgrade ~ â 2 ISOLDE 1.92 µa * Upgrade ~ â 5 Future n beams EURISOL > 2 GeV / 4 MW 1-2 GeV / 5 MW * 1350 pulses/h 3.2â10 13 ppp 1 : assembled by the High Intensity Protons working group. [CERN/AB working group mandated to (i) collect the present and foreseeable needs for high-intensity proton beams, (ii) analyze the capabilities of the CERN accelerator complex, (iii) compare possible improvements and (iv) recommend an upgrade path.] Report of the High Intensity Proton Working Group, CERN-AB-2004-022 OP/RF R.G. 16 16/11/2004

HIP-WG recommendations In the short term, to define in 2004 and start in 2005 the 3 following projects: New multi-turn ejection for the PS. Increased intensity in the SPS for CNGS (implications in all machines). 0.9 s PSB repetition time. In the medium term, to work on the design of Linac 4, to prepare for a decision of construction at the end of 2006. In the long term, to prepare for a decision concerning the optimum future accelerator by pursuing the study of a Superconducting Proton Linac and by exploring alternative scenarios for the LHC upgrade. R.G. 17 16/11/2004

Medium term estimates Performance in 2010 with (i) a PSB repetition period of 0.9 s, (ii) 7 10 13 ppp in the SPS and (iii) Linac4 injecting in the PSB (i) (i)+(ii) (i)+(ii)+(iii) Standard operation CNGS double batch Linac 4 Basic user s request CNGS flux [ 10 19 pot/year] 4.7 (4.5) 7.0 (4.5) 7.5 (4.5) 4.5 FT spills [ 10 5 /year] 3.2 (3.4) 3.0 (5.1) 3.3 (5.6) 7.2 East Hall spills [ 10 6 /year] 1.5 1.4 1.5 1.3 NTOF flux [ 10 19 pot/year] 1.6 1.5 1.6 1.5 ISOLDE flux [µa] 3.1 2.6 6.4 1.9 [nb. of pulses/hour] 2200 1810 2240 1350 72 bunch train for LHC at PS exit [ 10 11 ppb] 1.5 1.5 2 1.3 (2*) * ultimate R.G. 18 16/11/2004

Comparison of drivers at CERN Present accelerator Linac2 Replacement accelerator Linac4 Improvement LHC upgrade ν physics beyond CNGS INTEREST FOR RIB beyond ISOLDE Physics with k and µ 50 160 MeV H + H - + 0 (if alone) 0 (if alone) 0 (if alone) 2.2 GeV RCS* for HEP 1.4 2.2 GeV 10 250 kw + 0 (if alone) + 0 (if alone) PSB PS SPS 2.2 GeV/mMW RCS* 2.2 GeV/50 Hz SPL* SC PS*/** for HEP 5 Hz RCS*/** 1 TeV SC SPS*/** 1.4 2.2 GeV 0.01 4 MW 1.4 2.2 GeV 0.01 4 MW 26 50 GeV Intensity x 2 26 50 GeV 0.1 4 MW 0.45 1 TeV Intensity x 2 + + +++ (super-beam, β- beam, ν factory) +++ (super-beam, β- beam, ν factory) + (too short beam pulse) 0 (if alone) +++ 0 (if alone) ++ 0 (if alone) 0 + ++ ++ (ν factory) 0 +++ +++? 0 +++ * with brightness x2 ** need new injector(s) R.G. 19 16/11/2004

Possible planning CDR 2 RF test place ready 3 MeV test place ready Linac4 approval SPL approval LHC upgrade R.G. 20 16/11/2004

SPSC ( VILLARS ) RECOMMENDATIONS FOR THE FUTURE OF FIXED TARGET PHYSICS R.G. 21 16/11/2004

SPSC (Villars 2004) Gatignon Report on the SPSC Villars Meeting September 22-28 2004 John Dainton University of Liverpool, GB (on behalf of the SPSC) R.G. 22 16/11/2004

SPSC Recommendations (p.21) CERN 2004 R.G. 23 16/11/2004

SPSC Recommendations (p.62) ν physics has noble history at CERN ν physics is in a new golden era - CERN beginning again pivotal global role CNGS commitment to ~ end of decade vital - 2006 important: COMPASS then CNGS @ end 06 - CNGS crucial up to 2011 (window @ 4.5x10 19 pot/yr) - CNGS + COMPASS? multi-turn xtraction longer running period - no compelling case for extending CNGS beyond 2011 @ realisable pot/yr (< ~ 3x 4.5x10 19 pot/yr) C2GT R.G. 24 16/11/2004

SPSC Recommendations (p.63) Future neutrino facilities offer great promise for fundamental discoveries (such as CP violation) in neutrino physics, and a post-lhc construction window may exist for a facility to be sited at CERN. CERN should arrange a budget and personnel to enhance its participation in further developing the physics case and the technologies necessary for the realization of such facilities. This would allow CERN to play a significant role in such projects wherever they are sited. A high-power proton driver is a main building block of future projects, and is therefore required. A direct superbeam from a 2.2 GeV SPL does not appear to be the most attractive option for a future CERN neutrino experiment as it does not produce a significant advance on T2K. We welcome the effort, partly funded by the EU, concerned with the conceptual design of a β-beam. At the same time CERN should support the European neutrino factory initiative in its conceptual design. R.G. 25 16/11/2004

SPSC Recommendations (p.95) fixed target physics at CERN - > 2011: physics must be vibrant, important, leading ion+ion 2009 (synergy with LHC) rare flavour 2009 (synergy with LHC) fundamental physics with - p atoms hadron structure: GPDs if appropriate? dynamics: low energy, resonance ν physics: evaluation & R&D @ CERN p-driver superbeam detector global context NF synergies with other science? SPL? All but HI benefit from/require high intensity RCPSB RCPS R.G. 26 16/11/2004

CONSEQUENCES FOR RADIO-ACTIVE ION BEAMS R.G. 27 16/11/2004

Medium / long term The driving forces for the definition of the future proton injectors at CERN are (in ~ order of influence): The LHC upgrade (H3 network inside CARE), which is likely to recommend a 1 TeV injector (+ probably Linac4). Neutrino physics (BENE network inside CARE), which is now encouraged to aim directly at a neutrino factory (compatible with a proton driver at 20-50 GeV) FT physics (SPSC Villars), which favors a high power proton driver at CERN, with an energy ~ 20-50 GeV or even higher. An adequate scenario has to be prepared (procedure under design ). For the needs of the RIB community to be taken into account, a clear message must be communicated at the highest level of the organization. Personal conviction: considering the ambitions, the proposal will be very costly, and arbitration will be unavoidable (~ 2008-2010). R.G. 28 16/11/2004

Short / medium term Before Linac4 is available, the only possibility to increase the proton flux to ISOLDE is by reducing the PSB repetition period (0.9 s has been defined by the HIP working group as a reasonable short term goal). The AB management has soon to decide about it (meeting on December 6). Approval will be more difficult than initially foreseen because: Consequences for the equipments are extensive, and significant efforts are going to be necessary for debugging; Group Leaders are less and less favorable The drawbacks for not doing it are mostly for ISOLDE, and less than originally thought, because of the SPSC preference for FT which is less demanding in terms of PSB cycles. The SPSC clearly states that: CNGS should receive the foreseen flux (4.5 10 19 pot/year), Efforts should be made to increase the SPS intensity and potential proton flux per year, with the objective of reducing the number of cycles for CNGS in favor of COMPASS. The result would be no upgrade for ISOLDE in the short term, and even a reduction of the number of cycles with respect to today (~ -30 %) For the needs of the RIB community to be taken into account, a clear message must be communicated at the highest level of the organization. R.G. 29 16/11/2004

FINAL WORD R.G. 30 16/11/2004

On the bright side The resources available for proton linac developments have remarkably increased during the past 2 years: clear support to the IPHI-CERN collaboration from all partners involved successful request for E.U. resources in favor of Coordinated Accelerator Research in Europe (CARE), including the HIPPI Joint Research Activity attribution of complementary resources by the CERN DG to help fulfill the work programme of the E.U. approved activities strong involvement of Russian laboratories with the help of the ISTC many laboratories (in E.U. and in Russia) are jointly working in a coordinated way, a 3 MeV test place will be available at CERN in 2007, prototypes for linac4 accelerating structures will be available within 2 years However, enthusiasm and support must be sustained, because H- source development is lagging behind Too little is done on the superconducting linac part Information of the physics committee(s) has to be improved to strengthen conviction (need for deeper investigation of alternatives). R.G. 31 16/11/2004

On the gloomy side For the short term, the reduction of the PSB repetition period to 0.9 s is not guaranteed to be approved. WARNING! For the longer term, the recommendations from the Villars meeting: do not take into account the needs of the physics community interested in Radio-active Ions, have poorly rated the consensual proposal established between neutrino and RIB physicists, based on a large water Cherenkov detector in the Frejus tunnel + SPL + beta-beam. R.G. 32 16/11/2004