cern awake project status edda gschwendtner

CERN AWAKE Project Status

Edda Gschwendtner

2

Outline

• Introduction• Project organization• AWAKE at CNGS• AWAKE at West Area• Bunch Compression• Other issues• Summary

E. Gschwendtner, ENTM, 20/11/2012

Introduction

AWAKE: A Proton Driven Plasma Wakefield Acceleration Experiment

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, ENTM, 20/11/2012 3

4

Introduction

June 2012: Official CERN AWAKE project : project-budgetmandate sent by S. Myers to CERN departments

produce parts of CDR under CERN responsibilityCDR includes detailed budget, CERN manpower and schedule plans for

design, construction, installation and commissioning.

Deliverables: End 2012: preliminary report summarizing the ongoing study to the A&T sector Management

Q1 2013: Conceptual Design Report to the A&T sector Management and the SPSC.


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Proton Driven Plasma Wakefield Acceleration


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’

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AWAKE Physics and R&D Program• Measure bunch-modulation of the proton beam.• Learn in detail about the modulation process through comparisons of data/simulations. • Use a wide variety of diagnostics (transition radiation, direct measurement of fields, spectrometer,

…) to understand the process in detail.• Vary a number of parameters (density, electron injection point, …) to learn dependence on

parameters.• Try out compressed proton bunch to understand scaling with proton bunch length higher

gradients expected.• Measure parameters of accelerated electron bunch (energy spread , transverse emittance, …) and

find dependence on parameters compare to simulations

• Use the knowledge we gain to design a new set of experiments leading to real collider application.

• In parallel: continue studying producing short, high-energy proton bunches.

Time-scale proposed by collaboration: • End 2014: Demonstrate 1% uniformity and complete operational 10m plasma cell(s) ready for beam in 2015


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AWAKE Collaboration25 institutes: Germany, UK, Portugal, USA, France, India, China, Norway, USA

• Spokesperson: Allen Caldwell, MPI• Deputy spokesperson: Matthew Wing, UCL

• Experimental coordinator: Patric Muggli, MPI– Plasma cell, electron diagnostics, optical diagnostics,– Electron source

• Simulations coordinator: Konstantin Lotov, Budker INP– Proton/electron beam in plasma cell

• Accelerator coordinator: Edda Gschwendtner, CERN– CERN AWAKE Project Leader See next slide


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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 Chapochnikova

WP1: Project ManagementEdda Gschwendtner


A& T sector management:Engineering, Beams, Technology Departments

Injectors and Experimental Facilities Committee (IEFC)

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.


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Proton Beam Specifications


Parameter 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

Parameter 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!

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Beam Specifications


Parameter Value

Beam Energy 5 or 10 or 20 MeV

Bunch intensity 108 electrons

Bunch length 0.165mm<l<1mm

Repetition rate 0.03 Hz

Transverse norm. emittance

< 25 mm mrad

Transverse beam size (at beta*=?m)

??

Angle(mrad) ~5-20 mrad

Electron beam specifications

Laser:30fs, 800nm, ~TW.

R & D facility: frequent access to plasma cell, laser, etc… needed.

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Experimental Layout


Plasma-cellProton beam dump

RF gun

Laser

Laser dump

OTRStreak camera

CTREO diagnostic

e- spectrometer

e-

SPSprotons

~3m

10m 15m20m >10m

10m

13E. Gschwendtner, ENTM, 20/11/2012

West Area

CNGS

SPS

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Facility Site I: CNGS


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


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CNGS – AWAKE Facility


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: Separate CNGS target area from upstream area:

Add shielding wall Allows to cool-down target/horn Keep flexibility in case CNGS would restart

Use hadron stop as beam dump

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

Present Layout

New Layout

1 QTG removed

2 QTLD

X

1 QTLD + 1 QTS

3 QTLF

X1 QTS removed


Chiara Bracco

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!


Chiara Bracco


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

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CNGS – Infrastructure• Survey:

– 1-2 months, ~60kCHF

• Access, fire, safety system:– Exists, modifications needed– Existing access could be moved down the tunnel to create ‘control room area’

in access gallery.

• Electricity– Infrastructure exists, modification needed

• Cooling and Ventilation– Infrastructure exists, modifications needed:

• E.g.: overpressure and temperature controlled service gallery


With today’s beam-line and experimental area design (+needs from equipment) start studies on services infrastructure estimates expected by end Dec 2012!

Dominique MissiaenRui Nunes, Silvia GrauDavide BozziniMichele Battistin

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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

• Collimator upstream the target must be remotely removed.

• Civil engineering (drilling holes) – Activation level to be analyzed and precautions defined.

• Tritium issue:– Evaporator to be installed independently of AWAKE facility, so OK.


Helmut Vincke

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Facility Site II: West Area


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.

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


Chiara Bracco

West Area - Radiation Constraints


Consequences to meet RP constraints: 1. For a surface installation of dump: bend beam by about 10°or2. 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.

beam on dump: particular problem from muonsMake sure that radiation levels from muons are below RP optimization criteria:

CERN fence

West hall

100 mSv/year

10 mSv/year

Muon dose rate expected for beam@dump impact at 2 m below surface at a bending angle of 2 degree (no losses at beam line considered).

CERN FENCE

• 1E-3 mSv/h (contours in picture) correlates to less than 10 mSv/year. Compliant with RP optimization limit for public for ultimate and nominal beam.

OK

• Radiological situation inside West Area to be further investigated (size of radiological classified areas, additional shielding on surface, air activation…)• New situation at 300 GeV with a beam impact at -1.4m to be studied.

West Area – RP IssuesHelmut Vincke


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West Area - Civil Engineering Aspects


Trench work concentrate on TT4/TT5

3.5m x 3.5m trench, 100m long~1.1MCHF, ~10months

66 kV power line

18kV

– Technical gallery! • 18kV & 66kV power lines:

backbone of the CERN grid• Installation until end 2012

Dig trench only in TT5

TT4TT5

John Osborne, Antoine Kosmicki

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West Area – Proton Beam Line


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

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West Area – Experimental Area



TT4

TT5



Laser for seeding TI:sapphire

RF gun+

space for handling

Power supply laser

RF Gun cooling

Primary pump laser

Laser RF gun

Power supply

Laser diagnostic

SASclean area

Klystron

SASShielding

Hi Rad MAT

Rack




Plasma Cell

El. Spect. DetectorEl. Spect. Magnet

Sec.Beam.Diag

Optic table

Optic table

Rack

OTR screen

OTR screen

Pump turbo plasma

Camera

Optic table

DumpGallery

Junction laser system and proton

Entry point 1.20m depth

Distance floor / beam 600 mm

Gallery

Tunn

el h

all E

3

Gallery


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West Area – Beam Dump


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

Simulations of H. Vincke: for carbon used as core material significant increase in muon dose at a distance of 600m from beam dump at CERN fence (different for iron as core material). Results qualitatively confirmed by simulations from the FLUKA team. Further input from RP: carbon would be ideal for activation issues, however, high muon production might be show stopper for the current design.

Vasilis Vlachoudis, Thanasis Manousos

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West Area - Access System


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

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West Area – Infrastructure• Survey :

– 5 months, ~140kCHF

• Electricity– Primary substation is close (200m)– Existing infrastructure old– A lot must be refurbished, renewed…

• 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

• Safety, Fire system – To be studied.


With today’s beam-line and experimental area design (+needs from equipment) start studies on services infrastructure estimates expected by end Dec 2012!

Dominique MissiaenDavide BozziniMichele BattistinSilvia Grau

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CNGS vs West Area – Incomplete!


CNGS West Area

Proton beam line magnets + Exist - To be done

Beam instrumentation + Exist - To be done

Prompt dose issues(muon dose)

+ OK - Consequences on shielding, West Area classification on beam energy, and/or limited number of extractions!

Other radiation issues - Target chamber must be shielded: Target, horns. Need long cool-down to remove.

- Beam losses: need forward and lateral shielding

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 + Access system exists, - long distance to experimental area make ‘control room area’ in access gallery

- New access system

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CNGS vs West Area – Incomplete!


CNGS West Area

Electricity + Exists - needs some modifications

- To be done, refurbished, renewed,…

Cooling, ventilation + Exists- needs some modifications

- To be done refurbished, renewed,…

Storage issues + use storage gallery - TT4/TT5 is radioactive material storage area: full with stored magnets, etc… area needed in LS1. build new storage building.

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!

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Bunch Compression Studies in SPS

2 MDs: Bunch-rotation tests: 11 July 2012, 30 October 2012


T. Argyropoulos, H. Bartosik, T. Bohl, J. Esteban Muller, A. Petrenko, G. Rumolo, E. Shaposhnikova,H. Timko

Maximum axial electric field depends on bunch-length of drive beam! Strong interest to study bunch compression (Today SPS beam is 12cm long!)

Studies ongoing

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Possible Collaboration with CERNElectron 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

• 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:• Valves, …


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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 Enough input to start infrastructure studies and design

From preliminary studies– CNGS: Beam possible in 2015, when:

• Only reusing proton beam-line an no major modifications are needed (e.g. dismantling of CNGS target, horns,…)

• Underground area, so less RP issues– West Area: Beam not available before 2017:

• New magnets, build new storage area, trench (civil engineering), new service installations,…• Surface area RP issues

Collaboration with CERN for specific issues


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Additional slides


40E. Gschwendtner, ENTM, 20/11/2012

2.65m1.65m

TAG41

1.6m

2.6m

TSG40

5m

3.2mTSG41

1.75m

2.86m

TT41

TT41

1.55m

2.55m

TCV4

TCC4


41

Introduction


Driving force: Space charge of drive beam displaces plasma electrons.Restoring force: Plasma ions exert restoring force.

++++++++++++++ ++++++++++++++++

----- --- -------------------

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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. Start of bunch-modulation in controlled way: strong laser pulse

cern awake project status edda gschwendtner

Documents

proton beam

compressed proton bunch

official cern awake

bunchmodulationelectron

protondriven pwa experiment

cell simulations

drive beam

highenergy proton bunches