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CERN AWAKE Project Status Edda Gschwendtner for the CERN AWAKE Project Team. Outline. Introduction Project organization AWAKE at CNGS AWAKE at West Area SPS beam bunch compression Other issues Summary. Introduction. AWAKE: A Proton Driven Plasma Wakefield Acceleration Experiment
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CERN AWAKE Project StatusEdda Gschwendtnerfor the CERN AWAKE Project Team
Outline Introduction Project organization AWAKE at CNGS AWAKE at West Area SPS beam bunch compression Other issues Summary
Introduction AWAKE: A Proton Driven Plasma Wakefield Acceleration Experiment High Gradient Acceleration: needs high peak power and structures that can sustain high fields • LHC: 5 MV/m • ILC: 35 MV/m • CLIC: 100 MV/m • beam/laser-driven plasma: ~10 GV/m • Example: SLAC (2007) 50GV/m over 0.8m with electron-driven PWA some electrons doubled energy from 42GeV to 80GeV Advantage of proton driven plasma wakefield acceleration: • high stored energy available in the driver many kJ of stored energy Reduces drastically the number of required driver stages. Proof-of principle demonstration experiment proposed at SPS • first beam-driven wakefield acceleration experiment in Europe • the first Proton-Driven PWA experiment worldwide.
Introduction • June 2012: Official CERN AWAKE project: • project-budget • mandate sent by S. Myers to CERN departments • Identifythe best site for the installation of the facility on the SPS (West Area, CNGS) • Carry out a study covering the design of the proton beam-line, the experimental area and all interfaces and services at CERN. • produce parts of CDR under CERN responsibility • CDR includes detailed budget, CERN manpower and schedule plans for design, construction, installation and commissioning. • Deliverables: • Q1 2013: Conceptual Design Report to the A&T sector Management and the SPSC
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Proton Driven Plasma Wakefield Acceleration Produce an accelerator with mm (or less) scale ‘cavities’ Electron bunch Plasma cell (10m) Proton beam: drive beam (12cm) modulated in micro-bunches (1mm) after ~several meters drives the axial electric field Laser pulse: ionization of plasma and seeding of bunch-modulation Electron beam: accelerated beam injected off-axis some meters downstream along the plasma-cell, merges with the proton bunch once the modulation is developed. gas Plasma proton bunch laser pulse Particle-in-cellsimulationspredictaccelerationofinjectedelectronstobeyond 1 GeV.
AWAKE ExperimentalProgram Goal: • Proof-of-principle demonstration experiment • Long-term: design a new set of experiments leading to real collider application To get there: • study bunch-modulation of the proton beam ( axial electric field) • Measure parameters of the accelerated electron bunch • Comparison of data/simulations • Use variety of diagnostics (transition radiation, spectrometer,…) to understand process • Vary number of parameters (plasma density, electron injection point, beam intensity, bunch-length, emittance,… ) to learn dependence on parameters • Use compressed proton bunch to understand scaling with proton bunch length higher gradients expected. • In parallel: continue studying producing short, high-energy proton bunches. Time-scale proposed by collaboration: • End 2014: Demonstrate 0.1% uniformity and complete operational 10m plasma cell(s) ready for beam in 2015
AWAKE Collaboration 25 institutes: Germany, UK, Portugal, USA, France, India, China, Norway, USA • Spokesperson: Allen Caldwell, MPI • Deputy spokesperson: Matthew Wing, UCL • Experimental coordinator: PatricMuggli, MPI • Simulations coordinator: Konstantin Lotov, Budker INP • Accelerator coordinator: Edda Gschwendtner, CERN CERN AWAKE Project Leader See next slide
CERN AWAKE Project Structure A& T sector management: Engineering, Beams, Technology Departments CERN AWAKE Project Project leader: Edda Gschwendtner Deputy: Chiara Bracco Injectors and Experimental Facilities Committee (IEFC) WP4: Experimental Area Edda Gschwendtner WP1: Project Management Edda Gschwendtner WP3: Primary beam-lines Chiara Bracco WP2: SPS beam Elena Shaposhnikova Radiation Protection: Helmut Vincke Civil Engineering: John Osborne General Safety and Environment: Andre Jorge Henriques General Services: CV, EL, access, storage, handling
Beam Specifications Laser: 30fs, 800nm, ~TW • Relaxed proton beam requirements for the first years of run • However, long-term goal is to get shorter longitudinal beams • (Bunch-compression, Continue MDs!) • R & D facility: frequent access to plasma cell, laser, etc… needed.
Experimental Layout Laser e- spectrometer RF gun e- Proton beam dump 10m Plasma-cell ~3m Laser dump SPS protons OTR Streak camera CTR EO diagnostic 10m 15m 20m >10m
SPS CNGS West Area
CNGS • To compare with AWAKE: • 0.03 Hz cycle repetition rate • 3E11 protons per cycle • 4.9E16 protons/year • ~Factor 100 less protons/extraction • ~Factor 1000 less protons/year • CNGS is a running facility since 2006 at the desired beam parameters. • + Underground facility! • Proton beam and secondary beam-line fully equipped and running • All services (CV, EL, access, …) in place and used
CNGS – AWAKE Facility • AWAKE experimental facility at CNGS upstream the CNGS target: • Keep flexibility in case CNGS would restart • Main part of the beam is dumped in hadron stop (120 m) Access Gallery Service gallery Storage gallery TSG41 Target chamber Proton beam line TT41 Junction chamber Target Horn
CNGS Target Area (Target and Horns) Helmut Vincke (120 m) Access Gallery TSG41 Target chamber Proton beam line TT41 Junction chamber Target Horn • Separate CNGS target area from upstream area • Add shielding wall • Keeping strict access conditions for CNGS target area • Allows to cool-down target/horns for any further handling • Keep ventilation system to avoid corrosion, etc… in order to have easy handling for later dismantling (preventing 2nd WANF experience)
CNGS – Proton Beam Line Chiara Bracco Present Layout 1 QTS removed X X 1 QTG removed New Layout 3 QTLF 1 QTLD + 1 QTS 2 QTLD • Existing SPS extraction, no changes needed • Magnets exist • Beam instrumentation exists (some modifications/cabling) • Minor changes at the end of the proton-line for: • New final focusing • Interface between Laser and proton beam • Aperture ok, no conflict with integration.
CNGS – AWAKE Facility Shieldingwall RF gun+space for handling RF Gun cooling Klystron LaserRF Gun Primary pump laser SAS Power supply Optic table Laser for seeding TI:sapphire camera El. Spect. magnet SAS OTR screen Plasma Cell Optic table DIPOLE Ans Pardons Damien Brethoux Vincent Clerc Laserdiagnostic Junction laser system and proton Power supply laser
CNGS – Infrastructure RuiNunes, Silvia Grau DavideBozzini Michele Battistin, Dominique Missiaen • With today’s beam-line and experimental area design (+needs from equipment) • studies on services infrastructure are ongoing • estimates expected by end Dec 2012! • Access, fire, safety system • Exists, modifications needed • Existing access could be moved down the tunnel to create ‘control room area’ in access gallery. Modification of access system: ~50kCHF • Electricity • Infrastructure exists • Changes and/or extensions of the low voltage layout to be considered to adapt the sockets layout ~250kCHF • Cooling and Ventilation • Infrastructure exists, modifications needed: • E.g.: overpressure and temperature controlled service gallery • Survey • 1-2 months, ~60kCHF
CNGS – RP Considerations Helmut Vincke • Control room in CNGS access gallery possible, but needs • Dose rate due to prompt radiation low enough • Fresh air, no radioactive air from experiment • Appropriate access system • Assess beam loss in upstream part of TT41. • Beam is dumped on hadron stop No issue with prompt dose from muons • Installation of shielding wall between AWAKE experimental area and CNGS target area reduces dose rate inside the AWAKE area. • Assume that dose rate in AWAKE experimental area comes from CNGS target station and to lower level from surrounding activated wall. • First estimate for required wall thickness: 80cm of concrete • Civil engineering (drilling holes) • Activation level to be analyzed and precautions defined. • Collimator upstream the CNGS target must be remotely removed. • Tritium issue: • Evaporator to be installed independently of AWAKE facility, so OK.
Facility Site II: West Area Proposed in LOI, 2011 TT5 183 TT4 AWAKE TT61 Beam from TCC6 - SPS Until 2004: West Area used as experimental beam facility. West Area today: Proton beam line TT61: ~empty TT4 and TT5: storage area for (radioactive) magnets Needed during LS1
Helmut Vincke West Area – RP issues 450 GeV @ 2˚ tilted beam dump (impact at –2 m) 600 m Contour line 1E-3 uSv/h < 10 uSv/year AWAKE dump 10 mSv/year uSv/h West hall • Muon dose at CERN fence (10 uSv/year) and outside buildings (100 uSv/year) • feasible with dump design proposed by RP • Losses at beam line must be kept at a bare minimum (maximum of ~1012 protons per year + additional shielding required) • Dose inside Bldg. 183/TT5/TT4 • Bldg 183: many work shops and offices relocate them or reclassify areas + additional shielding • Access to n-TOF: either access restriction or several meters of shielding beside beam line • Air activation • Beam line + dump area needs to be confined from accessible areas • Dedicated ventilation system required CERN fence
West Area – Consequences • For a surface installation of dump: bend beam by about 10° • or • Dump impact at ~2 m underground: tilt beam by 2°. • Build a beam-trench in TT4/TT5 civil engineering • 300 GeV beam to fit into TT61 and TT4/TT5 • + • To cope with beam losses: shielding at surface to forward and lateral direction.
West Area - Civil Engineering Aspects John Osborne, Antoine Kosmicki Trench work concentrated on TT4/TT5 TT5 TT4 3.5m x 3.5m trench, 100m long ~1.1MCHF, ~10months 66 kV power line BUT: Technical gallery between TT4 and TT5! • 18kV & 66kV power lines: backbone of the CERN grid • Installation until end 2012 18kV Dig trench in TT5 and B183
West Area – Proton Beam Line Chiara Bracco Modification of TT66 8 new switching magnets TI 2 to LHC TT61 tunnel to west hall HiRadMat primary beam line (TT66) HiRadMat facility TT60 from SPS Time estimate: • New magnets and PC design: 3 years • Re-use existing equipment (inventory needed) cabling anyhow needed start only after LS1 • Magnets needed: • 8 MBS • 17 vertical bending magnets • 2 horizontal bending magnets • 25 Quads (18 in TT61 + 7 final focusing) • Power Converters needed: • ~ 10 units • Beam instrumentation needed: • ~15 BPMs • ~10 BTVs
West Area – Proton Beam Line Chiara Bracco To respect all geometric and RP constraints: reduce beam energy to 300 GeV OK for experiment b = 3.7 m s = 200 mm: feasible! m • +Old Line • New Line • - Tunnel technical gallery dump TT4 TT61 TT5 B183 ~2° angle Dump depth: 1.4 m m
West Area – Experimental Area Ans Pardons Damien Brethoux Vincent Clerc Laser, electron-source TT4 TT5 Plasma-cell diagnostics Beam-dump Technical galleries
West Area – Infrastructure DavideBozzini Michele Battistin RuiNunes Silvia Grau Dominique Missiaen VasilisVlachoudis ThanasisManousos • With today’s beam-line and experimental area design (+needs from equipment) • studies on services infrastructure ongoing • estimates expected by end Dec 2012! • Electricity • New 18kV supply from substation ME59 to existing substation • Complete new low voltage distribution • Cleaning of existing cable trays to host new EL and experiment cables • 750kCHF • Cooling and Ventilation • Pumping system, cooling towers, piping connections • need refurbishment, redoing, some of them could maybe be used • Separate ventilation systems for proton beam-line, experimental area and dump • Access system • New access point is necessary in place of TT61 • New sector for patrolling of new injection line with 1-2 sector doors • New sector and 1-2 emergency exit doors or material doors for AWAKE area • All EIS-beam connected (cabled) to BA7 • 200kCHF • Safety, Fire system to be studied • Survey • 5 months • ~140kCHF • Dump design ongoing
CNGS vs West Area – Incomplete! Further Studies Needed!
Bunch Compression Studies in SPS T. Argyropoulos, H. Bartosik, T. Bohl, J. Esteban Muller, A. Petrenko, G. Rumolo, E. Shaposhnikova,H. Timko • Maximum axial electric field from drive beam in the plasma-cell depends on bunch-length of drive beam! • Strong interest to study bunch compression • Bunch length reduced using rotation by 30% (as compared to adiabatic voltage increase) • still some room for improvement with jump to unstable phase (HW available after LS1) • Bunch intensity varied (PSB) from 2.6E11 to 3.6E11 protons per bunch (more stable bunches with Q20). • Round beam with emittance of ~2 um for intensity of 3E11 protons. 2 MDs: Bunch-rotation tests: 11 July 2012, 30 October 2012
Possible Collaboration of the AWAKE Collaboration with CERN Electron source: • Eventually UK did not get the funding to build the electron source. • AWAKE Collaboration tries to find other ways • EU synergy grant (deadline January 2013) • China, Novosibirsk (Budker-Institute) • Use PHIN injector as electron source? • To be clarified in next weeks. Laser: • Idea is that the laser for the electron source together with the laser for the plasma-source is provided by the experimental groups. • Will be tested with the plasma cell at institutes. • Must be well synchronized. • Collaboration with CERN useful though for installation, interface, safety,… Diagnostics: • Experimental groups provide diagnostics instrumentation, but CERN BE-BI very interested to collaborate Vacuum system: • Valve system is needed in the plasma-cell to let the beam pass from the beam-line into the plasma-cell lots of know-how in TE-VSC.
Summary Proton Driven Plasma Wakefield Acceleration is a unique accelerator R&D experiment at CERN. Studies for the CERN AWAKE facility are advancing well • SPS beam studies • proton beam-line design • experimental area • Input for infrastructure studies and design Collaboration of CERN with the AWAKE Collaboration for specific issues From preliminary studies • CNGS (underground area – fewer RP issues): Beam possible in 2015, when: • Only reusing proton beam-line and no major modifications are needed (e.g. dismantling of CNGS target, horns,…) • West Area (surface area – RP issues): Beam not available before 2017: • New magnets, build new storage area, trench (civil engineering), new service installations,… More detailed studies continue and will be summarized in the CDR to be delivered by March 2013!
1.55m 1.65m 2.65m 2.55m TAG41 5m TT41 TSG41 3.2m TCV4 TSG40 1.6m TT41 TCC4 2.6m 1.75m 2.86m E. Gschwendtner, ENTM, 20/11/2012 35
Mandate of CERN AWAKE Project • Identify the best site (West Area or CNGS) for installation of the facility on the SPS by carrying out a study covering: • The design of the proton beam-line from the SPS to the entry point of the plasma cell, to meet the required parameters. • The design of the downstream beam-line from the plasma cell to the beam dump. • The design the common beam-line for the proton, electron and laser light beam at the entry into the plasma cell. Specification of the parameters for these incoming beams. • The design of the experimental area (envelope) considering layout optimization of all components in the area. • The study of access possibilities and assess radiation and safety aspects. • The study of the general infrastructures (Civil Engineering, Access, CV, EL, transport, handling, control). • The physics program that could be carried out on each site. • The comparison of the cost and of the schedule of the alternative sites. • Based on the study, recommend a site for the facility and deliver the chapters, covering the beam line, the experimental area and all interfaces and services at CERN, in the conceptual design report (CDR) of the AWAKE CERN facility. The CDR should include the points mentioned in the section above plus the following information: • Specification of the baseline beam parameters to be used for the design. • Predictions of measurable quantities in the diagnostic instrumentation. • Specification of diagnostic instrumentation in the experimental area. • Design and interface with the electron beam up to the plasma cell. • Study all interfaces between the different systems (plasma cell, electron beam, proton beam, laser…) • Evaluation of time scale and costs of all items at a level needed for the CDR. • Evaluate dismantling feasibility and cost.
CNGS - Laser Integration with p-Beam Chiara Bracco Laser Last MBG • Laser mirror: • 20 m upstream entrance plasma cell • 12.5 m upstream of last MBG • 30.7 mm offset between proton and laser beam at mirror • needed clearance: 23mm OK! • Aperture along the line: OK • No conflict with integration studies! Proton Beam Last QTL
West Area - Access System RuiNunes • West Area: • Need new access system of ‘primary area type’ (higher level of risk exposure and radiation classfication) • Turnstile and material access door needed, passive beam stopper, • Interlock system shared with HiRadMat and LHC (to be modified) • De-coupled from nTOF area Existing/new beam line TT61 Access Point Access gallery for nTOF/TT61 nTOF Access Point Shielding/Civil Eng. Must leave path for access to nTOF
West Area – Beam Dump VasilisVlachoudis, ThanasisManousos • Various materials were studied in terms of temperature behavior: • Light materials (e.g. Carbon): significantly lower temperature increase than heavy materials. • But higher hadronic interaction length: higher muon production