Download - LHC status and commissioning plans. LHC in 4 slides Lest we forget Progress to date Present schedules Consequent plan for 2008

LHC status and commissioning plansLHC status and commissioning plans

LHC in 4 slidesLHC in 4 slides

Lest we forgetLest we forget

Progress to dateProgress to date

Present schedulesPresent schedules

Consequent plan for 2008Consequent plan for 2008

R.Bailey, DESY, December 2007R.Bailey, DESY, December 2007

LHC dipoles (1232 of them) operating at 1.9KLHC dipoles (1232 of them) operating at 1.9K

7TeV• 8.33T• 11850A• 7MJ


And plenty more magnets besides …And plenty more magnets besides …

Several thousand magnets

Thousands of Interconnects•Electrical•Fluids•Vacuum


And plenty of power circuits …And plenty of power circuits …

Several hundred Power Circuits


Lest we forget – QRLLest we forget – QRL

Installation started in sector 7-8 in July 2003Installation started in sector 7-8 in July 2003 Geometry, weld quality, procedures, leaks, support tables …Geometry, weld quality, procedures, leaks, support tables …

Installation finished November 2006 (sector 78 by CERN)Installation finished November 2006 (sector 78 by CERN)


Lest we forget – Main magnetsLest we forget – Main magnets

First magnet installed March 2005First magnet installed March 2005 Peak of ~1000 dipoles stored, allowed magnet sortingPeak of ~1000 dipoles stored, allowed magnet sorting

Last dipole lowered April 26Last dipole lowered April 26thth 2007 2007 CryostatingCryostating 425 FTE . years425 FTE . years Cold testsCold tests 640 FTE . years640 FTE . years TransportTransport 30’000 km underground at 2 km/h!30’000 km underground at 2 km/h!


Lest we forget – Triplets – Heat exchanger problemLest we forget – Triplets – Heat exchanger problem

During the pressure test of Sector 7-8 (25 November 2006) the corrugated heat During the pressure test of Sector 7-8 (25 November 2006) the corrugated heat exchanger tube in the inner triplet failed by buckling at 9 bar (external) exchanger tube in the inner triplet failed by buckling at 9 bar (external) differential pressure.differential pressure.

The inner triplet was isolated and the pressure test of the whole octant was The inner triplet was isolated and the pressure test of the whole octant was successfully carried out to the maximum pressure of 27.5 bar, thus allowing it successfully carried out to the maximum pressure of 27.5 bar, thus allowing it to be later cooled down.to be later cooled down.

Reduced-height of corrugations and annealing of copper near the brazed joint Reduced-height of corrugations and annealing of copper near the brazed joint at the tube extremities accounted for the insufficient resistance to buckling.at the tube extremities accounted for the insufficient resistance to buckling.

New tubes were produced with higher wall thickness, no change in corrugation New tubes were produced with higher wall thickness, no change in corrugation height at ends, and e-beam welded collars to increase distance to the brazed height at ends, and e-beam welded collars to increase distance to the brazed joint.joint.

Installation of these tubes was made Installation of these tubes was made in situin situ..


Lest we forget – Triplets – Supports problemLest we forget – Triplets – Supports problem

Q1 supports at IP 5L

On Tuesday March 27 2007 there was a serious failure in a high-pressure test at CERN of a Fermilab-built “inner-triplet”

series of three quadrupole magnets


Lest we forget – Triplets – Supports solutionLest we forget – Triplets – Supports solution

Requirements for repairRequirements for repair Must be implemented Must be implemented in situin situ Does not displace the fixed points of the assemblyDoes not displace the fixed points of the assembly React loads with sufficient stiffness to limit deflection at 150 kN design loadReact loads with sufficient stiffness to limit deflection at 150 kN design load Acts at any temperature between 300K and 2KActs at any temperature between 300K and 2K To be implemented in Q1 and Q3To be implemented in Q1 and Q3

Solution adoptedSolution adopted Affixed at Q1 non-IP end and at Q3 IP endAffixed at Q1 non-IP end and at Q3 IP end Transfer load at all temperaturesTransfer load at all temperatures Limits support deflectionsLimits support deflections Compound design with Invar rod and Compound design with Invar rod and

aluminium alloy tubealuminium alloy tube Attached with brackets to cold mass and Attached with brackets to cold mass and

cryostat outer vesselcryostat outer vessel

StatusStatus All triplets repaired by September All triplets repaired by September Problem solvedProblem solved


Commissioning of the power convertersCommissioning of the power converters

PC

18kV for the dipole circuits400V for the others

Water

UPS for all convertersabove 4 kA

DCCT

Short Circuit

UA, UJ, RR

tunnel, UJ

1720/1720 installed

Commissioning campaign on short circuitFrom mid 2006 to late 2007

100% commissioned


Machine commissioning without beam is by sectorMachine commissioning without beam is by sector

8 distinct sectors forcryogenic and powering

Picture today

Order was originally determined by installation sequence

78 81 45 34 56 67 23 12


Shielded bellows on the cold interconnects (PiMs)Shielded bellows on the cold interconnects (PiMs)


Plug in Module in equivalent cold positionPlug in Module in equivalent cold position


RF moleRF mole

Polycarbonate shell Diameter

34mm exterior 30mm interior

Total weight ~15 g (ball 8g)

RF characteristics 40MHz resonantcircuit

Generates 20V between copper electrodes

Battery powered Over 2hr lifetime

Capacitive coupling to BPM electrodes

1V ~5mV⇒ -45db Coupling

BPM trigger threshold at ~3mV


Commissioning of sector 45 (without triplet)Commissioning of sector 45 (without triplet)

LHC sector 4-5: 1st Cool-down (2007)

0

50

100

150

200

250

300

350

29-Jun-07

09-Jul-07

19-Jul-07

29-Jul-07

08-Aug-07

18-Aug-07

28-Aug-07

07-Sep-07

17-Sep-07

27-Sep-07

07-Oct-07

17-Oct-07

27-Oct-07

06-Nov-07

16-Nov-07

26-Nov-07

06-Dec-07

Time [days]

Tem

pera

ture

[K

]

Return Temperature to 4.5K Refrigerator Magnet Temperature (average over sector)

4.5K Refrigerator Supply Temperature

Water in the oil ofCompressor station

Leak to insulating vacuumStop for repair

Leak to insulating vacuumStop for repair

Almost readyfor powering


Beam testsBeam tests October 2004

October 2007


Performance goalsPerformance goals

Nearly all the parameters are variableNearly all the parameters are variable Number of particles per bunchNumber of particles per bunch Number of bunches per beamNumber of bunches per beam kkbb

Relativistic factor (E/mRelativistic factor (E/m00)) Normalised emittanceNormalised emittance nn

Beta function at the IPBeta function at the IP **

Crossing angle factorCrossing angle factor FF Full crossing angleFull crossing angle cc

Bunch lengthBunch length zz

Transverse beam size at the IPTransverse beam size at the IP **

FfkN

FfkN

Ln

b

yx

b*

22

44

2

*21/1

zcF

“Thus, to achieve high luminosity, all one has to do is make (lots of) high population bunches of low emittance to collide at high frequency at locations where the beam optics provides as low values of the amplitude functions as possible.” PDG 2005, chapter 25


Overall commissioning strategy for protons (estOverall commissioning strategy for protons (estdd. 2005). 2005)

Hardware commissioning

Machine checkout

Beam commissioning

43 bunch operation

75ns ops

25ns ops IInstall Phase II and MKB

25ns ops II

Stage A B C

No beam Beam

D

I.I. Pilot physics runPilot physics run First collisionsFirst collisions 43 bunches, no crossing angle, no squeeze, moderate intensities43 bunches, no crossing angle, no squeeze, moderate intensities Push performancePush performance Performance limit 10Performance limit 103232 cm cm-2-2 s s-1-1 (event pileup) (event pileup)

II.II. 75ns operation75ns operation Establish multi-bunch operation, moderate intensitiesEstablish multi-bunch operation, moderate intensities Relaxed machine parameters (squeeze and crossing angle)Relaxed machine parameters (squeeze and crossing angle) Push squeeze and crossing angle Push squeeze and crossing angle Performance limit 10Performance limit 103333 cm cm-2-2 s s-1-1 (event pileup) (event pileup)

III.III. 25ns operation I25ns operation I Nominal crossing angleNominal crossing angle Push squeezePush squeeze Increase intensity to 50% nominalIncrease intensity to 50% nominal Performance limit 2 10Performance limit 2 103333 cm cm-2-2 s s-1-1

IV.IV. 25ns operation II25ns operation II Push towards nominal performancePush towards nominal performance

*

bk

N

Optimise

Pileup

Losses

Beampower

Complexity

Minimise

)( *


LHCb during Stage ALHCb during Stage A

Displace bunches in one ring (n on m)Displace bunches in one ring (n on m) 4 per SPS cycle in 43 bunch, 16 per SPS cycle in 156 bunch mode4 per SPS cycle in 43 bunch, 16 per SPS cycle in 156 bunch mode

Dedicated runs for LHCb (n on n) ?Dedicated runs for LHCb (n on n) ?

Squeeze in point 8 (2m limit for ‘bad’ LHC dipole polarity)Squeeze in point 8 (2m limit for ‘bad’ LHC dipole polarity)

All values for All values for nominal emittancenominal emittance 7TeV7TeV

ParametersParameters Rates in 8Rates in 8

kkbb NN * 8* 8

(m)(m)

LuminosityLuminosity

(cm(cm-2-2ss-1-1))

Events/Events/

crossingcrossing

1 on 11 on 1 10101010 1010 1.8 101.8 102727 << 1<< 1

44 on 43 on 43 10101010 1010 7 107 102727 << 1<< 1

4 on 434 on 43 4 104 101010 1010 1.1 101.1 102929 0.150.15

4 on 434 on 43 4 104 101010 22 5.7 105.7 102929 0.760.76

16 16 on 156on 156 4 104 101010 22 2.3 102.3 103030 0.760.76

156156 on 156 on 156 4 104 101010 22 2.2 102.2 103131 0.760.76

156 on 156156 on 156 9 109 101010 22 1.1 101.1 103232 3.93.9

FfkN

Ln

b*

2

4

fk

LCrossEventrate

b

TOT/


Stage B physics runStage B physics run FfkN

Ln

b*

2

4

ParametersParameters Beam levelsBeam levels Rates in 1 and 5Rates in 1 and 5 Rates in 2 and 8Rates in 2 and 8

kkbb NN * 1,5* 1,5

(m)(m)

IIbeambeam

protonproton

EEbeambeam

(MJ)(MJ)


(cm(cm-2-2ss-1-1))

Events/Events/

crossingcrossing


(cm(cm-2-2ss-1-1))

Events/Events/

crossingcrossing

936936 4 104 101010 1111 3.7 103.7 101313 4242 2.4 102.4 103131 << 1<< 1 2.6 102.6 103131 0.150.15

936936 4 104 101010 22 3.7 103.7 101313 4242 1.3 101.3 103232 0.730.73 2.6 102.6 103131 0.150.15

936936 66 10 101010 22 5.6 105.6 101313 6363 2.9 102.9 103232 1.61.6 6.0 106.0 103131 0.340.34

936936 99 10 101010 11 8.4 108.4 101313 9494 1.2 101.2 103333 77 1.3 101.3 103232 0.760.76

Relaxed crossing angle (250 Relaxed crossing angle (250 rad)rad)

Start un-squeezedStart un-squeezed

Then go to where we were in stage AThen go to where we were in stage A

All values for All values for nominal emittancenominal emittance 7TeV7TeV 10m 10m * in points 2 and 8 (will not be like this)* in points 2 and 8 (will not be like this)

Protons/beam ≈ few 1013

fk

LCrossEventrate

b

TOT/

2

*21/1

zcF

Stored energy/beam ≤ 100MJ


Stage C physics runStage C physics run FfkN

Ln

b*

2

4

ParametersParameters Beam levelsBeam levels Rates in 1 and 5Rates in 1 and 5 Rates in 2 and 8Rates in 2 and 8

kkbb NN * 1,5* 1,5

(m)(m)

IIbeambeam

protonproton

EEbeambeam

(MJ)(MJ)


(cm(cm-2-2ss-1-1))

Events/Events/

crossingcrossing


(cm(cm-2-2ss-1-1))

Events/Events/

crossingcrossing

28082808 4 104 101010 1111 1.1 101.1 101414 126126 7.2 107.2 103131 << 1<< 1 7.9 107.9 103131 0.150.15

28082808 4 104 101010 22 1.1 101.1 101414 126126 3.8 103.8 103232 0.720.72 7.9 107.9 103131 0.150.15

28082808 55 10 101010 22 1.4 101.4 101414 157157 5.9 105.9 103232 1.11.1 1.2 101.2 103232 0.240.24

28082808 5 105 101010 11 1.4 101.4 101414 157157 1.1 101.1 103333 2.12.1 1.2 101.2 103232 0.240.24

28082808 5 105 101010 0.550.55 1.4 101.4 101414 157157 1.9 101.9 103333 3.63.6 1.2 101.2 103232 0.240.24

NominalNominal 3.2 103.2 101414 362362 10103434 1919 6.5 106.5 103232 1.21.2

fk

LCrossEventrate

b

TOT/

Nominal crossing angle (285 Nominal crossing angle (285 rad)rad)

Start un-squeezedStart un-squeezed

Then go to where we were in stage BThen go to where we were in stage B

All values for All values for nominal emittancenominal emittance 7TeV7TeV 10m 10m * in points 2 and 8 (will not be like this)* in points 2 and 8 (will not be like this)

Protons/beam ≈ 1014

2

*21/1

zcF

Stored energy/beam ≥ 100MJ


Stage A: routes through the commissioning phasesStage A: routes through the commissioning phases

Circulating beam

InjectionFirst turn

450GeVinitial

450GeVoptics

450GeV2 beams

450GeVIncrease I

Circulating beam

InjectionFirst turn

450GeVinitial

450GeVoptics

450GeVIncrease I

SnapbackRamp

Top energychecks

Top energyCollisions

SnapbackRamp

Top energychecksSqueeze

Squeeze

Pilotphysics

Ramp both beams

Squeeze both beams

Beam 2

Beam 1

2 beams450GeVCollisions

Experimentmagnets

OFF

DipolesOFF


Beam commissioning to 7 TeV collisionsBeam commissioning to 7 TeV collisions

RingsRings Total [days]Total [days]

1 Injection and first turn 2 4

2 Circulating beam 2 3

3 450 GeV – initial commissioning 2 4

4 450 GeV – detailed optics studies 2 5

5 450 GeV increase intensity 2 6

6 450 GeV - two beams 1 1

7 450 GeV - collisions 1 2

8a Ramp - single beam 2 8

8b Ramp - both beams 1 2

9 7 TeV – top energy checks 2 2

10a Top energy collisions 1 1

TOTAL TO FIRST COLLISIONS (beam time) 30

11 Commission squeeze 2 6

10b Set-up physics - partially squeezed 1 2

TOTAL TO PILOT PHYSICS RUN (beam time) 44


Stage A: First collisionsStage A: First collisions

Approx 30 days of beam time to establish first collisionsApprox 30 days of beam time to establish first collisions Un-squeezedUn-squeezed Low intensityLow intensity

Approx 2 months elapsed timeApprox 2 months elapsed time Given optimistic machine availabilityGiven optimistic machine availability

Continued commissioning thereafterContinued commissioning thereafter Increased intensityIncreased intensity SqueezeSqueeze


Staged commissioning plan for protonsStaged commissioning plan for protons

Hardware commissioning

450 GeV and 7TeV

2008 Machine checkout

Beam commissioning

450 GeV

Machine checkout

Beam commissioning

7TeV

43 bunch operation

Shutdown

B C

No beam Beam

ShutdownMachine checkout

Beam Setup

75ns ops 25ns ops I Shutdown

2009

No beam Beam

A


First beamFirst beam

Beam 2

Beam 1

Download - LHC status and commissioning plans. LHC in 4 slides Lest we forget Progress to date Present schedules Consequent plan for 2008

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