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CERN AWAKE Project Status
Edda Gschwendtnerfor the CERN AWAKE Project Team
2
Outline
• Introduction• Project organization• AWAKE at CNGS• AWAKE at West Area• SPS beam bunch compression• Other issues• Summary
E. Gschwendtner
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.
E. Gschwendtner 3
4
IntroductionJune 2012: Official CERN AWAKE project:
project-budgetmandate sent by S. Myers to CERN departments
Identify the 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 responsibilityCDR 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 SPSCE. Gschwendtner
5
Introduction
E. Gschwendtner
Driving force: Space charge of drive beam displaces plasma electrons.Restoring force: Plasma ions exert restoring force.
++++++++++++++ ++++++++++++++++
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+ + + + + + + + + + ++ + + + + + + + + + + + + + ++ + + + + + + + + + + + + + ++ + + + + + + + + + + + + + +-
- --
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Ez
Proton beam
plasma wavelength lp =1mm, (for typical plasma density of np = 1015cm-3 )
Maximal axial electric field: Ez,max = Nprotons/bunch
sz (rms bunch length) also drive beam sz of 1mm
But: SPS beam: rms length of sz~12cm Would need bunch-compression or Modulate long SPS bunch to produce a series of ‘micro-bunches’ in a plasma with a
spacing of plasma wavelength lp. Strong self-modulation effect of proton beam due to transverse wakefield in plasma Starts from any perturbation and grows exponentially until fully modulated
6
Proton Driven Plasma Wakefield Acceleration
E. Gschwendtner
Proton beam: drive beam (12cm)modulated in micro-bunches (1mm) after ~several metersdrives the axial electric field
Laser pulse: ionization of plasma and seeding of bunch-modulation
Electron beam: accelerated beaminjected off-axis some meters downstream along the plasma-cell, merges with the proton bunch once the modulation is developed.
Particle-in-cell simulations predict acceleration of injected electrons to beyond 1 GeV.
laser pulseproton bunch
gasPlasmaElectron bunchPlasma cell (10m)
Produce an accelerator with mm (or less) scale ‘cavities’
7
AWAKE Experimental ProgramGoal:• 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
E. Gschwendtner
8
AWAKE Collaboration
25 institutes: Germany, UK, Portugal, USA, France, India, China, Norway, USA
• Spokesperson: Allen Caldwell, MPI• Deputy spokesperson: Matthew Wing, UCL
• Experimental coordinator: Patric Muggli, MPI
• Simulations coordinator: Konstantin Lotov, Budker INP
• Accelerator coordinator: Edda Gschwendtner, CERNCERN AWAKE Project Leader See next slide
E. Gschwendtner
9
CERN AWAKE Project Structure
Radiation Protection: Helmut VinckeCivil Engineering: John OsborneGeneral Safety and Environment: Andre Jorge HenriquesGeneral Services: CV, EL, access, storage, handling
WP3: Primary beam-linesChiara Bracco
CERN AWAKE ProjectProject leader: Edda Gschwendtner
Deputy: Chiara Bracco
WP4: Experimental AreaEdda Gschwendtner
WP2: SPS beamElena Shaposhnikova
WP1: Project ManagementEdda Gschwendtner
E. Gschwendtner
A& T sector management:Engineering, Beams, Technology Departments
Injectors and Experimental Facilities Committee (IEFC)
10
Beam Specifications
E. Gschwendtner
Proton Beam Nominal
Beam Energy 450 GeV
Bunch intensity 3×1011 p
Number of bunches 1
Repetition rate 0.03 Hz
Transverse norm. emittance 3.3-3.5 mm
Transverse beam size (at b*=5m) 0.2 mm
Angle accuracy <0.05 mrad
Pointing accuracy <0.5 mm
Energy spread 0.34% (rms)
Bunch length 12 cm
Energy in bunch 21 kJ
Run-scenario Nominal
Number of run-periods/year 4
Length of run-period 2 weeks
Total number of beam shots/year (100% efficiency)
162000
Total number of protons/year 4.86×1016 p
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.
Electron Beam Value
Beam Energy 5 or 10 or 20 MeV
Bunch intensity 108-9 electrons
Bunch length 0.165mm<l<1mm
Laser: 30fs, 800nm, ~TW
11
Experimental Layout
E. Gschwendtner
Plasma-cellProton beam dump
RF gun
Laser
Laser dump
OTRStreak camera
CTREO diagnostic
e- spectrometer
e-
SPSprotons
~3m
10m 15m20m >10m
10m
12E. Gschwendtner
West Area
CNGS
SPS
13
Facility Site I: CNGS
E. Gschwendtner
CNGS
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 Parameters
Proton beam energy from SPS 400 GeV/c
Cycle repetition rate 0.17 Hz
Number of extractions/cycle 2
Protons per cycle 2x2.4E13
Proton pulse length 10.5 ms
Beam power (max.) 510 kW
Beam size at target ( )s 0.5mm
Protons/year 4.5E19
To compare with AWAKE:
0.03 Hz cycle repetition rate3E11 protons per cycle4.9E16 protons/year
~Factor 100 less protons/extraction ~Factor 1000 less protons/year
E. Gschwendtner 14
15
CNGS – AWAKE Facility
E. Gschwendtner
Target Horn
TSG41
Storage gallery
(120 m)
Proton beam line TT41 Junction chamber Target chamber
Access Gallery
Service gallery
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
16
CNGS Target Area (Target and Horns)
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)
E. Gschwendtner
Target Horn
TSG41
(120 m)
Proton beam line TT41 Junction chamber Target chamber
Access Gallery
Helmut Vincke
CNGS – Proton Beam Line• 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.
Present Layout
New Layout
1 QTG removed
2 QTLD
X
1 QTLD + 1 QTS
3 QTLF
X1 QTS removed
E. Gschwendtner 17
Chiara Bracco
E. Gschwendtner 18
Laser for seeding TI:sapphire
Plasma Cell
RF gun+
space for handling
Power supply laser
RF Gun cooling
Junction laser system and proton
OTR screen
Primary pump laser
Optic table
Klystron
Power supply
Laserdiagnostic
SAS
LaserRF Gun
Shielding wall
DIPOLE
SAS
El. Spect. magnet
Optic table
camera
CNGS – AWAKE Facility
Ans PardonsDamien BrethouxVincent Clerc
19
CNGS – Infrastructure
• 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
E. Gschwendtner
With today’s beam-line and experimental area design (+needs from equipment)
studies on services infrastructure are ongoing estimates expected by end Dec 2012!
Rui Nunes, Silvia GrauDavide BozziniMichele Battistin, Dominique Missiaen
20
CNGS – RP Considerations• 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.
E. Gschwendtner
Helmut Vincke
21
Facility Site II: West Area
E. Gschwendtner
TT61
TT4TT5
Beam from TCC6 - SPS
AWAKE
183
Proposed in LOI, 2011
West Area today:Proton beam line TT61: ~emptyTT4 and TT5: storage area for (radioactive) magnets Needed during LS1
Until 2004: West Area used as experimental beam facility.
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
West Area – RP issues
CERN fence
West hall
10 mSv/year
uSv/h
Contour line1E-3 uSv/h < 10 uSv/year
450 GeV @ 2˚ tilted beam dump (impact at –2 m)
AWAKEdump
600 m
E. Gschwendtner 22
Helmut Vincke
West Area – Consequences
E. Gschwendtner 23
1. For a surface installation of dump: bend beam by about 10°
or
2. 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
+3. To cope with beam losses: shielding at surface to forward and lateral direction.
24
West Area - Civil Engineering Aspects
E. Gschwendtner
Trench work concentrated on TT4/TT5
3.5m x 3.5m trench, 100m long~1.1MCHF, ~10months
66 kV power line
18kV
BUT: Technical gallery between TT4 and TT5! • 18kV & 66kV power lines: backbone of the CERN grid• Installation until end 2012
Dig trench in TT5 and B183
TT4
TT5
John Osborne, Antoine Kosmicki
West Area – Proton Beam Line
• 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
TT60 from SPS
TI 2 to LHC
HiRadMat facility
TT61 tunnel to west hall
HiRadMat primary beam line (TT66)
Modification of TT66
8 new switching magnets
Time estimate:– New magnets and PC design: 3 years– Re-use existing equipment (inventory needed)
cabling anyhow needed start only after LS1
E. Gschwendtner 25
Chiara Bracco
26
West Area – Proton Beam Line
E. Gschwendtner
dump
~2° angleDump depth: 1.4 m
TT61TT4TT5
technical gallery
+ Old Line•New Line- Tunnel
m
m
To respect all geometric and RP constraints: reduce beam energy to 300 GeV OK for experiment b = 3.7 m = 200 s mm: feasible!
Chiara Bracco
B183
27
West Area – Experimental Area
E. Gschwendtner
Ans PardonsDamien BrethouxVincent Clerc
TT4
TT5
Laser, electron-source
Plasma-cell
Beam-dump
diagnostics
Technical galleries
28
West Area – Infrastructure• 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
E. Gschwendtner
With today’s beam-line and experimental area design (+needs from equipment)
studies on services infrastructure ongoing estimates expected by end Dec 2012!
Davide BozziniMichele BattistinRui NunesSilvia GrauDominique MissiaenVasilis VlachoudisThanasis Manousos
29
CNGS vs West Area – Incomplete!
E. Gschwendtner
CNGS West Area
Proton beam line magnets + Exist - To be done
Beam instrumentation + Exist, some modifications needed - To be done
Prompt dose issues(muon dose)
+ OK - Consequences on shielding, West Area classification, on beam energy, and/or limited number of extractions!
Shielding issues - Target chamber must be shielded: Target, horns. Need long cool-down to remove.
- Beam losses: need forward and lateral shielding - Shielding for nTOF
Civil engineering -+ Drill holes only. - Dig trench in TT5- Technical gallery btw. TT4/TT5
Size of experimental area -+ OK, but tight + OK
Control room - Inside tunnel or ECA4 - New building needed
Access, fire, gas system + Exists, - long distance to access experimental area make ‘control room area’ in access gallery
- New access and fire/gas system
30
CNGS vs West Area – Incomplete!
E. Gschwendtner
CNGS West Area
Electricity + Exists - needs some modifications
- To be done, refurbished, renewed
Cooling, ventilation + Exists- needs some modifications
- To be done refurbished, renewed- Air tightness + dedicated ventilation system of installation required.
Storage issues + can use storage gallery - TT4/TT5 is radioactive material storage area: full with stored magnets, etc… area needed in LS1. Find space for stored material!
Beam dump + OK, exists - Must be newly built - lot of shielding needed- Optimization of dump design
Vacuum system - Exist for proton beam line - To be done
Survey - New network points in experimental area. 1-2 months
- New network point along beam line and experimental area, fiducials, … 5 months
Additional Safety Measures
- Laser - Klystron- …
- Laser- Klystron- ….
Further Studies Needed!
31
Bunch Compression Studies in SPS
2 MDs: Bunch-rotation tests: 11 July 2012, 30 October 2012
E. Gschwendtner
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.
32
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
collaborateVacuum 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.
E. Gschwendtner
33
SummaryProton 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!
E. Gschwendtner
34
Additional slides
E. Gschwendtner
CNGS - Laser Integration with p-Beam
Last QTL
Last MBG
Laser
Proton Beam
• Laser mirror: o 20 m upstream entrance plasma cello 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!
E. Gschwendtner 35
Chiara Bracco
36
West Area - Access System
E. Gschwendtner
Rui Nunes
TT61 Access Point
Existing/new beam
line
nTOFAccess Point
Access gallery for nTOF/TT61
Shielding/Civil Eng. Must leave path for
access to nTOF
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