Neutrino Town MeetingNeutrino Town MeetingCERN – May 14-16, 2012CERN – May 14-16, 2012

SPL R&D and Potential SPL R&D and Potential ApplicationsApplications

R. Garoby for the SPL team*

O. Brunner, S. Calatroni, O. Capatina, E. Ciapala, F. Gerigk, E. Montesinos,V. Parma, K.M. Schirm,+ I. Aviles Santillana **, R. Bonomi **, J. Chambrillon, P. Coelho Azevedo**, K. Liao, N. Valverde Alonso**

** supported by ESS

HP-SPL:HP-SPL:R&D ManagementR&D Management

R. G. – 15/05/2012 3

• R & D for a High Power SPL formally supported at CERN in view of multiple future potential applications

~1.7 MCHF and 6 FTEs / year

• Collaboration with ESS Fellows and procurement of klystron modulator for SM18

• French in-kind contribution Tuners, Helium tanks, use of Saclay 704 MHz high power test place…

• EC-supported programmes• EuCARD (WP10)

Development and test of beta=1 (CEA) and beta=0.65 (IN2P3) 5 cells cavities• CRISP (WP4)

Joint work with ESS and DESY EC-supported manpower for upgrading and exploiting the SM18 test place

• LAGUNA-LBNO EC-supported fellow for studying proton drivers at CERN using LP- or HP-SPL

• DOE-supported programme• BNL Development and test of a =1 cavity

ResourcesResources

SPL documentation in EDMS [ https://edms.cern.ch/nav/SLHC-000008 ] SPL meetings in Indico [ http://indico.cern.ch/categoryDisplay.py?categId=1893 ]

SPL documentation in EDMS [ https://edms.cern.ch/nav/SLHC-000008 ] SPL meetings in Indico [ http://indico.cern.ch/categoryDisplay.py?categId=1893 ]

R. G. – 15/05/2012 4

Organization (at CERN)Organization (at CERN)GuidelineGuideline

«Project-like» structure aimed at meeting the objectives of the HP-SPL R&D:• Building and testing a prototype cryomodule with 4 cavities• Updating CERN infrastructure and competence in superconducting RF technology• Preparing submission of future subjects of R&D [design and construction of a full-size cryomodule,

high power RF sources, HIPIMS (High Power Impulse Magnetron Sputtering)…]

Work UnitsWork Units-Design, construction and test of the prototype cryomodule (Leader: V. Parma)

- Components: Cryomodule, Cavities, RF items (Couplers, tuners, …), cryogenics equipment…- Assembly (with adequate tools): cavities string in clean room, inclusion in cryomodule- Tests: cavities in vertical cryostat, assembled cryomodule in bunker.- Upgrade of the SM18 infrastructure (Leader: O. Brunner)- HP water rinsing system and upgraded clean roon- Cryogenics for efficient operation at 2K- High power RF at 704 MHz (klystron, modulator, high power distribution)- Low Level RF and controls

-SC RF cavities technology (Leader: E. Ciapala)- Fabrication and processing- Test, diagnostics and analysis

HP-SPL:HP-SPL:Baseline Design ParametersBaseline Design Parameters

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Option 1 Option 2

Energy (GeV) 2.5 or 5 2.5 and 5

Beam power (MW)2.25 MW (2.5 GeV)

or

4.5 MW (5 GeV)

5 MW (2.5 GeV)

and

4 MW (5 GeV)

Protons/pulse (x 1014) 1.1 2 (2.5 GeV) + 1 (5 GeV)

Av. Pulse current (mA) 20 40

Pulse duration (ms) 0.9 1 (2.5 GeV) + 0.4 (5 GeV)

2 beam current 2 nb. of klystrons etc .

Ion species H−

Output Energy 5 GeVBunch Frequency 352.2 MHzRepetition Rate 50 HzHigh speed chopper < 2 ns(rise & fall times)

Required for muon production

Required for flexibility and low loss in accumulator

Required for low loss in accumulator

HP-SPL: Beam CharacteristicsHP-SPL: Beam Characteristics

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Medium cryomodule

High cryomodules

Ejec

tion

9 x 6=0.65 cavities

11 x 8=1 cavities

13 x 8=1 cavitiesto

EURI

SOL

Debunchers

To H

P-PS

and

/or A

ccum

ulat

or

High cryomodules

From

Lin

ac4

0 m0.16 GeV

110 m0.73 GeV

291 m2.5 GeV

500 m5 GeV

Segmented cryogenics / separate cryo-line / room temperature quadrupoles:-Medium (0.65) – 3 cavities / cryomodule-High (1) – 8 cavities / cryomodule

Low energy

Intermediate energy

High energy

HP-SPL: Block DiagramHP-SPL: Block Diagram

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Medium Medium cryomodule cryomodule

High High cryomodule cryomodule

Energy range: 160 MeV – 732 MeV5 cell cavitiesGeometrical : 0.65Maximum energy gain: 19.4 MeV/m54 cavities (9 cryomodules)Length of medium section: ~110.35 m

Energy range: 732 MeV – 5 GeV5 cell cavitiesGeometrical : 1Maximum energy gain: 25 MeV/m192 cavities (24 cryomodules)Length of high section: ~360 m

Energy gain (MeV/m)

1

5

1

0

1

5

Position (m)

100 200 300 400

HP-SPL: Cavities & CromodulesHP-SPL: Cavities & Cromodules

Status and Plans of R&DStatus and Plans of R&D

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CavitiesCavities (1/4)(1/4)

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CavitiesCavities (2/4)(2/4)

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CavitiesCavities (3/4)(3/4)

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CavitiesCavities (4/4)(4/4)

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SPL coupler: requirementsSPL coupler: requirements

Technical Choices

Single window coupler

Fixed coupler

With a Double Walled Tube

Mounted in clean room with its double walled tube horizontally in only one operation

Vertically below the cavity and will be a support for the cavity (first time worldwide)

With a HV DC biasing capacitor

Air cooled

14

RF Characteristics

f0 704.4 MHz

Power levels

1000 kW pulsed0.4 + 1.2 + 0.4 = 2.0 ms50 Hz (20 ms)100 kW average

Cavity design gradient 19-25 MV/m

Qext of input coupler 1.2 x 106

Input line Ø 100 / 43.5 mm = 50 Ω(from the cavity design)

Waveguides WR 1150

R. G. – 15/05/2012 15

15

SPL coupler: 2 designsSPL coupler: 2 designs

LHC-derivedSPS-derived

Doubled-wall tube

Ceramicwindow

Air cooling

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SPL coupler: test assemblySPL coupler: test assembly

• Four ‘vacuum lines’:– 4 cylindrical window

couplers– 4 planar disk window

couplers– 8 Double walled Tubes– 4 test boxes

• DESY clean process assembly– (Jlab also proposed to help)

• CERN LLRF measurements

• CEA RF power tests– (BNL also proposed to help)

16

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• Test box assembly not easy because of specific surfaces roughness needed for helicoflex

• Couplers assembly was also not easy because :– Couplers are heavy– Last connection has to be

done manually– Ok for few prototypes, not

for a large series

SPL coupler: clean room assembly SPL coupler: clean room assembly (DESY)(DESY)

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• Tests started with cylindrical window couplers

• Not baked out, static vacuum~ 2 x 10 -7 mbar– Wanted to check RF– Size of the test box 250 mm x 600 mm– Helicoflex

• Pulse mode process

• Reached > 1MW – 25 Hz – 2 ms (limited by heating due to lack of Cu platting)

SPL coupler: RF high power tests SPL coupler: RF high power tests (CEA)(CEA)

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System/Component/Activity Person(s) in charge Lab

Cavities/He vessel/tuner construction O.Brunner, O.Capatina, Th.Renaglia, F.Pillon, N.Valverde, M.Esposito, I.Aviles,G.Devanz

CERN

CEA-Saclay

SRF, magnetic shielding, Clean-Room activities, RF test stations (SM18)

E.Ciapala, T.Junginger, K.Shirm, J.Chambrillon, O.Brunner

CERN

RF Coupler E.Montesinos, G.Devanz

CERNCEA Saclay

Vacuum systems G.Vandoni CERN

Cryogenics, (cryo infrastructure SM18) U.Wagner, (O.Pirotte) CERN

Survey and alignment P.Bestman CERN

Cryo-module conceptual design R.Bonomi, D.Caparros, O.Capatina, P.Coelho, V.Parma,Th.Renaglia, A.Vande Craen, L.R.Williams

CERN

Cryo-module detailed design & Integration & Cryostat assembly tooling

Ph.Dambre, P.Duthil, P.Duchesne, S.Rousselot, D.Reynet

CNRS/IPNO-Orsay

SPL Machine architecture F.Gerigk CERN

ESS Cryomodule developments Ch.Darve ESS, Lund

Cryo-module Technical Coordination V.Parma CERN

ESS/CERN Fellow

ESS/CERN Fellow

ESS/CERN Fellow

ESS/CERN Fellow

Short cryomodule: the actorsShort cryomodule: the actors

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Short cryomodule: schematic layout Short cryomodule: schematic layout

Connection to cryo distribution line

CW transition

RF coupler, bottom left sideCavity additional support

1.7% Slope (adjustable 0-2%)

Cryo fill line (Y), top left Technical Service Module

EndModule

Phase sep.

Inter-cavity supportNow suppressed

Now suppressed

R. G. – 15/05/2012 21

1054

1021

• General concept and dimensions (not latest design)

7400

SSS

Courtesy P.Duthil (IPNO)(views S.Rousselot, IPN-Orsay)

Transport,dressing and alignment frame

Short cryomodule: vacuum vesselShort cryomodule: vacuum vessel

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4.5 K vapor generatorreservoir (with elect.heater)

standard support

Last cavity IC support

Ph.Separator pot

DN80 gate valve (single valve)

CWT 50 K heat intercept

(views S.Rousselot, IPN-Orsay)

Short cryomodule: technical service Short cryomodule: technical service modulemodule

Courtesy P.Duthil (IPNO)

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Courtesy W. Hofle @ 5th SPL collaboration Meeting

D. Valuch

LLRF under developmentLLRF under development

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Upgraded installation in SM18Upgraded installation in SM18

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Delivery of 704 MHz klystron and modulator

Preparation of SM18 infrastructure (cryogenics, RF, clean-room)

Cavities production

Cavities processing/RF testing

RF couplers

Clean room assembly of string

Cryomodule (& assy tooling) design

Cryomodule fabrication

Cryomodule assembly

Start cryomodule RF testing

Short cryomodule: master scheduleShort cryomodule: master schedule

R. G. – 15/05/2012 26

Related R & DRelated R & D

Nb coating of Cu cavities, using the HIPIMS (High Power Nb coating of Cu cavities, using the HIPIMS (High Power Impulse Magnetron Sputtering) technologyImpulse Magnetron Sputtering) technology

– In collaboration with Sheffield Hallam University (UK).– Supported in the context of the construction of LHC spare cavities.– Potentially very attractive technology for the SPL (raw material cost, mechanical Potentially very attractive technology for the SPL (raw material cost, mechanical

stiffness).stiffness).– First results on low beta 704 MHz cavity: end 2012First results on low beta 704 MHz cavity: end 2012

SPL ApplicationsSPL Applicationsto Proton Driversto Proton Drivers

R. G. – 15/05/2012 28

• New High Power PS (30-50 GeV, 2MW beam power) using the Low Power SPL (LP-SPL) Low Power SPL (LP-SPL) as injector.

• Feasibility Study based on the work for SPL and PS2 supported within the LAGUNA-LBNO DS.

50 GeV synchrotron-based proton 50 GeV synchrotron-based proton driverdriver

Long baseline experiment (2300 km)CERN-Pyhasalmi (Finland)

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PS2 parameters: reminder…PS2 parameters: reminder…

Parameter unit PS2 PS

Injection energy kinetic GeV 4.0 1.4

Extraction energy kinetic GeV 20 - 50 13 - 25

Circumference m 1346 628

Max. bunch intensity LHC (25ns) ppb 4.0 x 1011 1.7 x 1011

Max. pulse intensity LHC (25ns) ppp 6.7 x 1013 1.2 x 1013

Max. pulse intensity FT ppp 1.0 x 1014 3.3 x 1013

Linear ramp rate T/s 1.5 2.2

Repetition time (50 GeV) s ~ 2.5 1.2/2.4

Max. stored energy kJ 800 70

Max. effective beam power kW 320 60

29

R. G. – 15/05/2012 30

PS2 integration at CERN: reminderPS2 integration at CERN: reminder

30PAC 2009 Vancouver PS2 Design Optimization, M.Benedikt

PS2

SPL

Linac4

SPL to PS2

PS

PS/LEIR to SPS / PS2

SPS

PS2 to SPS

– “Straight” H- inj. line SPL PS2 avoiding large bending radii to minimise Lorentz stripping of H-.

– Minimum length of inj. line TT10 PS2 for ions and protons from PS complex.

– Minimum length HE line PS2 SPS.

R. G. – 15/05/2012 31

SPL-based 5 GeV – 4 MW proton drivers have been designed [SPL + 2 fixed energy rings (accumulator & compressor)] which meet these requirements

References:– SPL based proton driver/ R. Garoby, talk at NuFact06,

http://nufact06.physics.uci.edu/Workshop/Slides/RGaroby_SPL3_Pdriver.ppt– Feasibility Study of Accumulator and Compressor for the 6-bunches SPL-based Proton Driver / M. Aiba,

CERN-AB-2008-060– A first analysis of 3-bunches and 1-bunch scenario for the SPL-based Proton Driver / M. Aiba, CERN-AB-

Note-2008-048-BI– Beam Stability in the SPL Proton Driver Accumulator for a Neutrino Factory at CERN / E. Benedetto,

http://nufact09.iit.edu/wg3/wg3_benedetto-splstability.ppt, to be published– SPL-based Proton Driver for a Neutrino Factory at CERN, M. Aiba, E. Benedetto, R. Garoby, M. Meddahi,

poster nb.25 (this workshop)

Parameter Basic value Range

Beam energy [GeV] 10 5 - 15

Burst repetition rate [Hz] 50 ?

Number of bunches per burst (n) 4 1 – 6 ?

Total duration of the burst [s] ~ 50 40 - 60

Time interval between bunches [s] (tint)

16 ~ 50/(n-1)

Bunch length [ns] 2 1 - 3

Specifications(from ISS report)

HP-SPL based proton driver: principle HP-SPL based proton driver: principle (1/2)(1/2)

R. G. – 15/05/2012 32

1. Beam accumulation– Accumulator ring

» Charge exchange injection» n x 100s accumulation time» Isochronous (=0): beam frozen longitudinally to preserve p/p » No RF (=> minimum impedance)» 1-6 bunches of ~120 ns length

2. Bunch compression- Compressor ring

» Large RF voltage (large stored energy & minimum RF power) (=> bunch rotation on stored energy)

» Large slippage factor => rapid phase rotation in few x10s, » ~2ns rms bunch length @ extraction to the target (=> moderate Q

because of dispersion)

• Synchronization between rings- Ratio of circumferences guaranteeing correct positioning of successive bunches inside the compressor without energy change in any ring

HP-SPL based proton driver: principle HP-SPL based proton driver: principle (2/2)(2/2)

R. G. – 15/05/2012 33

Accumulation Duration = 400 s

Compression t = 0 s

t = 12 s

t = 24 s

t = 36 s

etc. until t = 96 s

Accumulator[120 ns pulses

-60 ns gaps]

SPL beam[42 bunches -

21 gaps]Compressor

[120 ns bunch -V(h=3) = 4 MV]

Target[2 ns bunches

– 6 times]

Generation of 6 bunchesGeneration of 6 bunches

R. G. – 15/05/2012 34

-40 -20 0 20 40-2

-1

0

1

2

x' (

mra

d)

x (mm)

Injection Rotated

-10 -5 0 5 10-0.6

-0.4

-0.2

0.0

0.2

0.4

0.6 Injection Rotated

y' (

mra

d)

y (mm)

-40 -20 0 20 40-0.15

-0.10

-0.05

0.00

0.05

0.10

0.15 Injection Rotated

dE (

GeV

)

RF phase/3 (deg.)

-3 -2 -1 0 1 2 30

5

10

15

Cou

nts/

bin

(%, b

in=

0.2

deg)

RF phase/3 (deg)

Rotated=1.98 ns

from M. Aiba

Bunch rotation before ejectionBunch rotation before ejection

R. G. – 15/05/2012 35

SPL for proton driver Output beam Parameters Values Parameters Values

Kinetic beam energy 5 GeV Kinetic beam energy 5 GeV Repetition rate 50 Hz Repetition rate 50 Hz Average current during the burst 40 mA No. of bunches per cycle 6 Beam power 4 MW Bunch length (r.m.s.) ~2 ns Bunch spacing ~12 s

Transverse emittance (r.m.s., physical) 3 mm-mrad

Accumulator Compressor Parameters Values Parameters Values

Circumference 318.5 m Circumference 314.2 m Transition gamma 6.33 Transition gamma 2.3 RF voltage - RF voltage 4 MV Harmonics number - Harmonic number 3 No. of arc cells 24 No. of arc cells 6 Super periodicity 2 Super periodicity 2 Nominal transverse tune 7.77/ 7.67 Nominal transverse tune 10.79/5.77 No. of turns for accum. 400 No. of turns for comp. 36 Maximum no. of bunches 6 Maximum no. of bunches 3

Main quadrupole Bore radius Field gradient Magnetic length

56 mm 5.5 T/m 1.2 m

Main quadrupole Bore radius Field gradient Magnetic length

148 mm 7.1 T/m 1.9 m

Main bending Full gap Full width Field stength Magnetic length

103 mm 162 mm

1.7 T 1.5 m

Main bending Full gap Full width Field strength Magnetic length

125 mm 379 mm

5.1 T 3 m

from M. Aiba

Main parametersMain parameters

R. G. – 15/05/2012 36

K1

K2

D1

D2

D3

D4

T1

T2

T3

T4

p z

Beam delivery on 4 targets & hornsBeam delivery on 4 targets & horns

Principle:• Use of 2 bipolar kickers (or bipolar pulsed magnets): ± 45˚ rotation wrt the z axis• K1 (K2) deflects to D1 and D3 (D2 and D4)• Need of 1 compensating dipole per beam line (1 angle for each target):

Apply a symmetry in the system

keff

EL

B

2998.0

)sin(Angle of deflection (rad)

Kinetic energy(GeV)Magnetic length (m)

Magnetic field (T)2000mm

T1 T2

T4 T3

z

K1 K2

D1 D2

D3 D4

T1 T2

T3 T4

zp

3D view

side view

E. Bouquerel – IPHC, EUROnu meeting, March 27, 2012

>>KEY PARAMETER<<

SummarySummary

R. G. – 15/05/2012 38

Technology (1/2)Technology (1/2)

Presently, the HP-SPL R&D:Presently, the HP-SPL R&D:

•progresses at a good pace, leading to the high power test of a short 4 cavities cryomodule in 2014.•allows testing the validity of new concepts that should result in significant savings (RF couplers, SS He tanks, Cryomodule design…)•can potentially be used in multiple projects at CERN as well as outside (ESS, MYRRHA) and benefits from external support (ESS and EU programmes)•is a means for CERN to embed inside the network of labs involved in superconducting RF technology (CEA, IN2P3, DESY, JLAB, FNAL, ANL…) and re-establish in-house competence in that field at the state-of-the-art level•drives infrastructural upgrades (e.g. electro-polishing facility, clean room, high power RF at 704 MHz…) which will be beneficial for other development (LHC main RF, Crab cavities, HIE IDOLDE…)

R. G. – 15/05/2012 39

Technology (2/2)Technology (2/2)

Important future R&D subjectsImportant future R&D subjects

•HOM damper for beam stability at high current•Cavities in view of reaching the expected performance/simplifying fabrication/evaluating alternative solutions (Nb on Cu)•Cryomodule towards a full size prototype•RF amplifiers for reducing cost•Power supply for high power amplifier for reducing cost

R. G. – 15/05/2012 40

Accelerator designAccelerator design

• The SPL accelerator design is «mature» and stable

• In the context of the LAGUNA-LBNO:– The LP-SPL design will be adapted to the requirements of the HP-PS– The HP-SPL design will be briefly revisited and completed with the design of the

accumulation ring

• Other applications may require resuming/refining accelerator design:– e+/e- acceleration in the ERL of the Linac-Ring option of LHeC– LEP-3– LP-SPL remains a back-up option for the LHC injector complex…