1. CERN AWAKE Project Status Edda Gschwendtner for 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

3. 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

4. Introduction June 2012: Official CERN AWAKE project: project-budget
mandate 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 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
E. Gschwendtner

5. Introduction + - Ez
Proton beam
Driving force: Space charge of drive beam displaces plasma electrons.
Restoring force: Plasma ions exert restoring force.
 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
E. Gschwendtner

6. Proton Driven Plasma Wakefield Acceleration
 Produce an accelerator with mm (or less) scale ‘cavities’
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.
laser pulse
proton bunch
gas
Plasma
Electron bunch
Plasma cell (10m)
 Particle-in-cell simulations predict acceleration of injected electrons to beyond 1 GeV.
E. Gschwendtner

7. AWAKE Experimental Program
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
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, CERN
CERN AWAKE Project Leader  See next slide
E. Gschwendtner

9. 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)
WP1: Project Management
Edda Gschwendtner
WP2: SPS beam
Elena Shaposhnikova
WP3: Primary beam-lines
Chiara Bracco
WP4: Experimental Area
Edda Gschwendtner
Radiation Protection: Helmut Vincke
Civil Engineering: John Osborne
General Safety and Environment: Andre Jorge Henriques
General Services: CV, EL, access, storage, handling
E. Gschwendtner

10. Beam Specifications Laser: 30fs, 800nm, ~TW
Proton Beam
Nominal
Beam Energy
450 GeV
Bunch intensity
3×1011 p
Number of bunches 1
Repetition rate
0.03 Hz
Transverse norm. emittance 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
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
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.
E. Gschwendtner

11. Experimental Layout e- Plasma-cell Proton beam dump Laser dump
RF gun
Laser
dump
OTR
Streak camera
CTR
EO diagnostic
e- spectrometer e-
SPS
protons
~3m
10m
15m
20m
>10m
10m
E. Gschwendtner

12. SPS
CNGS
West Area
E. Gschwendtner

13. Facility Site I: CNGS
E. Gschwendtner

14. CNGS To compare with AWAKE: 0.03 Hz cycle repetition rate
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 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
E. Gschwendtner

15. 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
Service gallery
Target
Horn
TSG41
Storage gallery
(120 m)
Proton beam line TT41
Junction chamber
Target chamber
Access Gallery
E. Gschwendtner

16. CNGS Target Area (Target and Horns)
Helmut Vincke
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)
Target
Horn
TSG41
(120 m)
Proton beam line TT41
Junction chamber
Target chamber
Access Gallery
E. Gschwendtner

17. CNGS – Proton Beam Line X Chiara Bracco
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
1 QTS removed
E. Gschwendtner

18. CNGS – AWAKE Facility Ans Pardons Damien Brethoux Vincent Clerc
Shielding wall
RF gun + space for handling
RF Gun cooling
Klystron
Laser RF 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
Laser diagnostic
Power supply laser
Junction laser system and proton
E. Gschwendtner

19. CNGS – Infrastructure Access, fire, safety system Electricity
Rui Nunes, Silvia Grau
Davide Bozzini
Michele Battistin,
Dominique Missiaen
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
With today’s beam-line and experimental area design (+needs from equipment)
studies on services infrastructure are ongoing
 estimates expected by end Dec 2012!
E. Gschwendtner

20. 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.
E. Gschwendtner

21. Facility Site II: West Area
Proposed in LOI, 2011
TT61
TT4
TT5
Beam from TCC6 - SPS
AWAKE
183
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
E. Gschwendtner

22. West Area – RP issues 600 m Helmut Vincke
uSv/h
Contour line
1E-3 uSv/h < 10 uSv/year
450 2˚ tilted beam dump (impact at –2 m)
AWAKE
dump
600 m
CERN fence
West hall
10 mSv/year
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
E. Gschwendtner

23. 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.
E. Gschwendtner

24. 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
E. Gschwendtner

25. West Area – Proton Beam Line
Chiara Bracco
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
Magnets needed:
8 MBS
17 vertical bending magnets
2 horizontal bending magnets
25 Quads (18 in TT final focusing)
Power Converters needed:
~ 10 units
Beam instrumentation needed:
~15 BPMs
~10 BTVs
Time estimate:
New magnets and PC design: 3 years
Re-use existing equipment (inventory needed)
 cabling anyhow needed
 start only after LS1
E. Gschwendtner

26. 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
dump
~2° angle
Dump depth: 1.4 m
+ Old Line
New Line
- Tunnel
technical
gallery
B183
TT5
TT4
TT61 m
E. Gschwendtner

27. West Area – Experimental Area
Ans Pardons
Damien Brethoux
Vincent Clerc
Laser, electron-source
TT4
TT5
Plasma-cell
diagnostics
Beam-dump
Technical galleries
E. Gschwendtner

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
Davide Bozzini
Michele Battistin
Rui Nunes
Silvia Grau
Dominique Missiaen
Vasilis Vlachoudis
Thanasis Manousos
With today’s beam-line and experimental area design (+needs from equipment)
studies on services infrastructure ongoing
 estimates expected by end Dec 2012!
E. Gschwendtner

29. CNGS vs West Area – Incomplete!
Proton beam line magnets
+ Exist
- To be done
Beam instrumentation
+ Exist, some modifications needed
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
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
E. Gschwendtner

30. CNGS vs West Area – Incomplete!
Electricity
+ Exists
- needs some modifications
- To be done, refurbished, renewed
Cooling, ventilation
- 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
- …
- ….
 Further Studies Needed!
E. Gschwendtner

31. 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
2 MDs: Bunch-rotation tests: 11 July 2012, 30 October 2012
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.
E. Gschwendtner

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 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.
E. Gschwendtner

33. 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!
E. Gschwendtner

34. Additional slides
E. Gschwendtner

35. CNGS - Laser Integration with p-Beam
Chiara Bracco
Last MBG
Laser
Proton Beam
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!
Last QTL
E. Gschwendtner

36. West Area - Access System
Rui Nunes
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
TT61 Access Point
Existing/new beam line
nTOF
Access Point
Access gallery for nTOF/TT61
Shielding/Civil Eng. Must leave path for access to nTOF
E. Gschwendtner