LAGUNA meetingLAGUNA meetingSeptember 7 - 10, 2010

CAES – CNRS – Aussois - FRANCE

Prospective Proton Drivers for Prospective Proton Drivers for neutrino facilities at CERNneutrino facilities at CERN

8/09/2010

R. Garoby

R.G. 7/09/20102

OUTLINEOUTLINE IntroductionIntroduction Plan for the injectors of LHCPlan for the injectors of LHC Plan for the SPLPlan for the SPL Summary of optionsSummary of options

R.G. 7/09/20103

IntroductionIntroduction

R.G. 7/09/20104

Outcome of Chamonix 2010Outcome of Chamonix 2010• Until the end of 2009 the favored scenario for the LHC luminosity upgrade

included the construction of new injectors (LP-SPL and PS2) to replace the PSB and PS, plus the upgrade of the SPS.

• During the Chamonix 2010 workshop, an alternative scenario was sketched, based on extensive consolidation and upgrade of the existing accelerators. That was associated with: an updated planning of increase of performance of the LHC a lessening of the required beam characteristics the statement that the cost of constructing the new accelerators would not be

affordable.

• As a result, a revised Scientific Strategy was prepared and included in the Medium Term Plan (approved by the Finance Committee in its August version). It includes: the continuation of Linac4, the systematic consolidation and upgrade of the existing accelerators to make

them able to fulfil reliably the needs of the High Luminosity LHC until ~2030, the conclusion of the PS2 and LP-SPL studies at short term, with the publication

of a “light” CDR to allow for resurrecting the option if necessary at a later date, “generic” R & D for a high power SPL in view of neutrino applications.

R.G. 7/09/20105

Plan for the injectors of LHCPlan for the injectors of LHC

R.G. 7/09/20106

Linac4Linac4Li

nac4

Lina

c4

Goals

Although it is designed to be capable of becoming the low energy front end of the SPL, the present (and only approved) goals of Linac4 are:

- to replace Linac2 (50 MeV protons, operational since 1979)- to double the potential brightness achievable by the PS Booster.

R.G. 7/09/20107

Linac4: main characteristics Linac4: main characteristics

Structures and klystrons dimensioned for 50 Hz Power supplies and electronics dimensioned for 2 Hz, 1.2 ms pulse.

Re-use of LEP RF components: klystrons, waveguides, circulators.

Ion species H−

Output Energy 160 MeVBunch Frequency 352.2 MHzMax. Rep. Rate 2 HzMax. Beam Pulse Length 1.2 msMax. Beam Duty Cycle 0.24 %Chopper Beam-on Factor 65 %Chopping scheme:

222 transmitted /133 empty bucketsSource current 80 mARFQ output current 70 mALinac pulse current 40 mAN. particles per pulse 1.0 × 1014

Transverse emittance 0.4 mm mrad

Max. rep. rate for accelerating structures: 50 Hz

160/50 MeV factor 2 in 2) same tune shift with twice the intensity.

Chopping at low energy to reduce beam loss in PSB.

H- charge exchange injection and painting in PSB

Lina

c4Li

nac4

R.G. 7/09/20108

CCDTL PIMS

3MeV

50MeV 94MeV 160MeV

Drift TubeLinac

18.7 m3 tanks3 klystrons4.7 MW111 PMQs

Pi-Mode Structure

22 m12 tanks8 klystrons~12 MW12 EMQuads

Cell-Coupled Drift TubeLinac25 m21 tanks7 klystrons7 MW21 EMQuads

RF accelerating structures: 4 types (RFQ, DTL, CCDTL, PIMS)Frequency: 352.2 MHzDuty cycle: 0.1% phase 1 (Linac4), 3-4% phase 2 (SPL), (design: 10%)

Linac4: 80 m, 18 klystrons

Ion current:40 mA (avg.),65 mA (peak)

CHOPPERRFQ

Chopper & Bunchers3.6 m11 EMquad3 cavities

Radio FrequencyQuadrupole3 m1 Klystron550 kW

H-

3MeV45keV

RF volumesource(DESY)45 kVExtrac.

DTL

Linac4: Block diagramLinac4: Block diagramLi

nac4

Li

nac4

R.G. 7/09/20109

Linac4: layoutLinac4: layout

9

• Linac4 is a normal-conducting H− linac at 160 MeV energy, made of 4 types of 352 MHz accelerating structures, matched to the increasing beam energy. A beam chopper at low energy allows modulating the linac beam pulse to minimise losses in the ring. A beam dump at linac end allows setting-up of the beam, will be displaced when connecting to the SPL.

• The Linac4 project includes important modifications to the PSB injection region (higher injection energy, H- stripping).

Linac4 tunnel and surface equipment building

160 MeV

100 MeV

50 MeVLina

c4

Lina

c4

R.G. 7/09/201010

Milestones

• End CE works: December 2010

• Infrastructure:2011

• Installation:2011 - 2012

• Commissioning: 2013 - 2015

• Modifications PSB: shut-down 2015/16

• On-line for physics:

2016

ID Task Name

1 Linac4 project start

2 Linac systems

3 Source and LEBT construction, test

4 Drawings, material procurement

5 RFQ construction and commissioning

6 Accelerating structures construction

7 Klystron prototype production

8 Klystrons production

9 Transfer line construction and installation

10 Magnets construction

11 Power converters construction

12 Building and infrastructure

13 Building design and construction

14 Infrastructure installation

15 PS Booster systems

16 PSB injection elements construction

17 Installation and commissioning

18 Test stand operation

19 Cavities testing, conditioning

20 Cabling, waveguides installation

21 Accelerator installation

22 Klystrons, modulators installation

23 Hardware tests

24 Front-end commissioning

25 DTL1 commissioning

26 Linac accelerator commissioning

27 Transfer line commissioning

28 PSB modifications

29 PSB commissioning with Linac4

30 PSB beam ready for PS

01/01

01/04

Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q32008 2009 2010 2011 2012 2013 2014

Linac4: planningLinac4: planning

2013 -

20152016

?

Lina

c4

Lina

c4

R.G. 7/09/201011

PSB, PS and SPSPSB, PS and SPS

Objectives

• Until the implementation of HL-LHC in the LHC (~2020), guarantee the availability of beam with adequate characteristics at injection (possibly beyond nominal),

• As soon as HL-LHC is implemented and for as long as it will operate (~2030), guarantee that the beam delivered by the injectors will meet its needs

PS

B,

PS

and

SP

SP

SB

, P

S a

nd S

PS Extensive

&continuous

consolidation

Upgrade

R.G. 7/09/201012

PSB & PS upgradesPSB & PS upgradesIncrease of the PS brightness up to the level required by HL-LHC (including

margin for beam loss in the successive accelerators), by increasing the transfer energy from PSB to PS, and implementing all the necessary improvements in the PS

PS

B,

PS

and

SP

SP

SB

, P

S a

nd S

PS

• New power supplies (PSB dipoles and transfer line)• New magnets (transfer line)• Upgrade of RF power systems (beam loading etc.)• Additional beam instrumentation• Cures against collective effects• Cures/mitigation measures against e-clouds• More feedback loops…

R.G. 7/09/201013

SPS upgradesSPS upgrades

Increase of the SPS brightness and maximum intensity up to the level required by HL-LHC (including margin for beam loss in transfer line and LHC)

PS

B,

PS

and

SP

SP

SB

, P

S a

nd S

PS

• Treatment of vacuum chamber (reduction of SEY)• Upgrade of RF power systems (increased RF power etc.)• Impedance reduction (kickers, cavities, etc.)• Cures against collective effects (damping systems)• Upgrade of beam dump• Upgrade of beam instrumentation• Collimators (?)• ?

R.G. 7/09/201014

Plan for the SPLPlan for the SPL

R.G. 7/09/201015

•Prepare for future potential physics programmes (Neutrinos, RIB)

•Update CERN generic competences in superconducting RF

•Synergy with other applications outside of CERN

SP

L R

& D

SP

L R

& D

Motivation for the SPL R & DMotivation for the SPL R & D(1/2)(1/2)

R.G. 7/09/201016

• Preserve the possibility of new injectors at long term

PSB

SPS

Linac4

LP-SPL

PS

LHC / sLHC

160 MeV

1.4 GeV4 GeV

26 GeV50 GeV

450 GeV

7 TeV

Linac250 MeV

Proton flux / Beam power

PS2

1978

1975

1959

2008

LP-SPL: Low Power-Superconducting Proton Linac PS2: High Energy PS (~ 5 to 50 GeV – 0.3 Hz)sLHC: “Super-luminosity” LHC (up to 1035 cm-2s-1)

PS2

SPL

LINAC4

SPS

PS

Motivation for the SPL R & DMotivation for the SPL R & D(2/2)(2/2)

SP

L R

& D

SP

L R

& D

R.G. 7/09/201017

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 .

SPL: main characteristicsSPL: main characteristics

Re-use of LEP RF components in Front-end (Linac4)

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 (Neutrino Factory)

Required for flexibility and low loss in accumulator

Required for low loss in accumulatorGeneral features

Options

SP

L R

& D

SP

L R

& D

R.G. 7/09/201018

SC-linac [160 MeV 5 GeV] with ejection at intermediate energy

Length: ~500 m

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

2 an

d/or

Acc

umul

ator

High cryomodules

From

Lin

ac4

0 m0.16 GeV

110 m0.73 GeV

291 m2.5 GeV

500 m5 GeV

SPL: Block diagramSPL: Block diagramS

PL

R &

DS

PL

R &

D

R.G. 7/09/201019

Frequency/temperature:

704 MHz and 2 K,

Accelerating gradient (=1 cavity): 25 MV/m “on average” (= with a high yield) is very challenging and may be costly (in terms of reprocessing), 20 MV/m seems more achievable but will have an impact on linac length (or energy).

High-power RF cavity tests of fully equipped High-power RF cavity tests of fully equipped cryo-modules are mandatory for realistic SPL cryo-modules are mandatory for realistic SPL layout estimates!!layout estimates!!

Ref.: Assessment of the basic Parameters of the CERN SPL, CERN-AB-2008-067-BI-RF,http://cdsweb.cern.ch/record/1136901/files/CERN-AB-2008-067.pdf

Cavities parametersCavities parametersS

PL

R &

DS

PL

R &

D

R.G. 7/09/201020

Medium cryomodule

High 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

CryomodulesCryomodulesS

PL

R &

DS

PL

R &

D

R.G. 7/09/201021

Prototype cryomodulePrototype cryomodule

P.Coelho Moreira de Azevedo

SP

L R

& D

SP

L R

& D

R.G. 7/09/201022

Coordinator External partners

RF hardware (low level & high power)

E. Ciapala Cockcroft Institute, ESS + (FNAL, SNS, JLAB, ANL)

Cavities (structures & auxiliary equipment)

W. Weingarten CEA-Saclay, CNRS-Orsay, TRIUMF, Stony Brook + (JLAB, SNS)

Cryomodule (cryostat & cryogenics) V. Parma CEA-Saclay, CNRS-Orsay, Stony Brook + (FNAL)

Beam dynamics (beam parameters) A. Lombardi CEA-Saclay, TRIUMF, Soltan Institute, ESS

Architecture (layout & geometry, extraction, transfer)

F. Gerigk

Surface treatment and vacuum S. Calatroni

Mechanical design and construction

O. Capatina

Working Groups

Study leader: R. Garoby

OrganizationOrganization

Structured storage for all SPL documentation in EDMS Structured filing of all SPL meetings and workshops in Indico Structured filing of all collaboration meetings in Indico

SPL Collaboration

SP

L R

& D

SP

L R

& D

R.G. 7/09/201023

R & D subjects until 2015R & D subjects until 2015

(in continuity with the work previously done for the LP-SPL)

•R & D towards a high duty cycle H- source (continuation after end of SLHC-PP ?)

•Study of the optimum high power RF architecture for a high power SPL

•Design, construction and test of superconducting RF cavities(704 MHz – 5 cells – =1)

•Development of high power RF coupler, HOM damper and adaptation of tuner

•Upgrade of the SM18 test place [2 K cooling + pulsed RF source at704 MHz (1 MW @ 50 Hz )]

•Pulsed high power RF tests of contiguous cavities in a single cryostat

•Design, construction and test a high power klystron modulator

•Design, construction and test of a prototype cryomodule equipped with 8 =1 cavities

Treated in sLHC-PP

Partly addressed in

sLHC-PP

Partly addressed in

“EuCARD”Partly

supported by French “in-kind”

contrib.Partly

supported by ESS

Org

aniz

atio

n an

d pl

anni

ngO

rgan

izat

ion

and

plan

ning

R.G. 7/09/201024

Planning for cavities and Planning for cavities and cryomodulecryomodule

2011 2012 2013 2014 2015

Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4SM18 - 2K Cryogenics

Vcryo.

X

SM18modulator

1 2

SM18 - 704 MHz High Power RF X

High Power RF couplers

4 >4 >8

Superconductingcavities

>4 >8

Assembled string of 4 cavities

X

Horiz. short cryom. (4 cav.)

X

Equipped horiz. short cryom.

X

High power RF tests in short cryo.

X

Assembled string of 8 cavities X

8 cavities cryomodule

X

Equipped cryomodule

X

High power RF tests in full CM

X

From ESS CERN design

~ In-phase with ESS

design update

SP

L R

& D

SP

L R

& D