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Page 1: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

Riken, Nov. 2002 ALICE at LHC J. Schukraft 1

Heavy Ions @ LHC Heavy Ions @ LHC Heavy Ions @ LHC Heavy Ions @ LHC

Heavy Ion Physics Heavy Ion Physics at LHCat LHC

LHC machineLHC machine

ALICEALICECollaborationDetectorPerformance

Page 2: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft2

Physics@LHC: Physics@LHC: CaveatCaveat

long distance QCD is difficult to predictlong distance QCD is difficult to predict Theory well known, not so its consequences or manifestation HEP@LHC: Theory unknown, but each candidate makes precise predictions

the fate of 'expectations' at SPS and RHICthe fate of 'expectations' at SPS and RHIC some expectations turned out right: SPS: strangeness enhancement RHIC: particle ratios, jet-quenching(?)

some turned out wrong: SPS: large E-by-E fluctuations RHIC: multiplicity dN/dy

a number of unexpected surprises: SPS: J/Psi suppression RHIC: elliptic flow, 'HBT-puzzle'

lesson when preparing ALICE at LHClesson when preparing ALICE at LHC guided by theory and expectations, but stay open minded !

'conventional wisdom''conventional wisdom' soft physics: smooth extrapolation of SPS/RHIC necessary, but boring ???

hard physics: new domain at LHC

Predictions are notoriously difficult, Predictions are notoriously difficult, in particular if they concern the future..in particular if they concern the future..

BIG Step ahead: BIG Step ahead: SPSSPS RHICRHIC LHCLHC x 28x 28 x 12x 12

Page 3: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft3

Hard Probes @ Hard Probes @ LHCLHC

LHC: the full 'spectrum' LHC: the full 'spectrum' soft -> semihard -> hard (>> 20 GeV) difficult to overcome power law with Luminosity !

high pt important in order to leave even tails of 'hydrodynamics'

factor 10 every 2-3 GeVfactor 10 every 2-3 GeV

X 2000X 2000

Page 4: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft4

Jets in ALICE |Jets in ALICE ||<0.9|<0.9

Reasonable rate up to ET ~300 GeV

2.8 102.8 1044

1.2 101.2 1055

8.1 108.1 1055

1.5 101.5 1077

4.9 104.9 101010

accepted accepted jets/monthjets/month

1.1 101.1 10-4-4200200

4.8 104.8 10-4-4150150

3.5 103.5 10-3-3100100

7.7 107.7 10-2-25050

3.5 103.5 102255

jets/eventjets/eventppt t jet >jet >

(GeV/c)(GeV/c)

First TRD studies ~ 1Hz trigger rate for central PbPb collisions and pt jet > 100 GeV/c

real jets triggers 0.7/sfalse triggers 0.3/s

Pb Pb rates:

ppL = 1030cm-2s-

1

ideal energy for jet-quenching:ideal energy for jet-quenching: around 100 GeVaround 100 GeV pQCD applicable jets measurable above soft background energy loss still relatively large effect E/E ~ O(10%), decreasing with E !

Page 5: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft5

Heavy Quarks & QuarkoniaHeavy Quarks & Quarkonia copious heavy quark productioncopious heavy quark production charm @ LHC ~ strange @ SPS hard production => 'tracer' of QGP dynamics (statistical hardonization ?) 2 mc ~ saturation scale => change in production ? jet-quenching with heavy quarks visible in inclusive spectra ?

Y dY d/dy LHC ~ 20 x RHIC/dy LHC ~ 20 x RHIC Y will probably need higher Lumi at RHIC even at LHC Y'' is difficult

Y productionY production

RHICRHIC LHCLHC

R. Vogt, hep-ph/0205330

Page 6: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft6

few hundred per month(from K.Kajantie, K.Eskola)

dNch/d ~ 2500

What multiplicity do we expect?What multiplicity do we expect? old estimates: dN old estimates: dNchch/dy 2000 - 8000, /dy 2000 - 8000, can we extrapolate from RHIC data ?can we extrapolate from RHIC data ?

Page 7: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft7

Initial Initial ConditionsConditions

<0.2<0.2~0.5~0.5~1~10 0 (fm/c)(fm/c)

4-104-101.5-4.01.5-4.0<1<1QGP QGP (fm/c)(fm/c)

2x102x1044(?)(?)7x107x1033101033VVff(fm(fm33))

15-4015-403.5-7.53.5-7.52.52.5 (GeV/fm(GeV/fm33))0=1fm0=1fm

22-8 x10-8 x1033700700-1500-1500430430dNdNchch/dy/dy

550055002002001717ss1/21/2(GeV) (GeV)

LHCLHCRHICRHICSPSSPSCentral collisionsCentral collisions

my pre-RHIC guess (QM2001)my pre-RHIC guess (QM2001) still expect conditions to be significantly different only LHC will give the final answer !

Significant gain in Significant gain in , V, , V, x 10x 10 SPS -> LHC SPS -> LHC

x 3-5x 3-5 RHIC -> LHC RHIC -> LHC

Page 8: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft8

The Soft StuffThe Soft Stuff

Freeze-out Hyper surfaceFreeze-out Hyper surface

SPSSPS

LHCLHC

changes in expansion dynamics & freeze-out ARE expectedchanges in expansion dynamics & freeze-out ARE expected will the measured transverse HBT volume (finally) increase ? thermal freeze-out temperature ? how will charm fit into particle ratios ? will anisotropic flow change shape of freeze-out volume ? Event-by-Event fluctuations ? measurement accuracy increases ~ #particles

AGSAGS RHICRHIC LHC ?LHC ?

Biggest surprise Biggest surprise would be none..would be none..

Page 9: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft9

LHC LHC StatusStatus

the long & winding road to LHCthe long & winding road to LHC first discussion on HI in LHC: 1990 LHC approved 1994 /1996 start-up several times postponed

CERN financial problemsCERN financial problems some 20% cost overrun (~800 MCHF) solution in sight reduce non- LHC program, bank loans, savings, 1 year delay

machine well into constructionmachine well into construction civil engineering almost finished ~ 20 production magnets tested

LHC start-up: LHC start-up: April 2007April 2007

first short heavy ion run: end 2007

External Machine External Machine Review Committee: Review Committee:

'Tight, but feasible''Tight, but feasible'

Atlas cavernAtlas cavern

Page 10: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft10

LHC LHC MagnetsMagnets

Main DipoleMain Dipole Transfer LinesTransfer Lines

MQWMQWInsertion (Japan)Insertion (Japan)

Page 11: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft11

Heavy Ions in LHCHeavy Ions in LHC energyenergy Ebeam = 7 x Z/A [TeV]s = 5.5 TeV/A (Pb-Pb), 14 TeV (pp)

beamsbeams possible combinations: pp, pA, AA constant magnetic rigidity/beam ('single magnet')

expected heavy ion running ~ 6 weeks heavy ion runs, typically after pp running (like at SPS) initial emphasis on Pb-Pb pp and pA comparison runs intermediate mass ion (eg Ar-Ar) to vary energy density

later options: different ion species, lower energy AA and pp

luminosity luminosity low L runs: avoid pile-up in TPC

high L runs: max rate in muon arm

Page 12: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft12

ALICE Set-upALICE Set-up

HMPID

Muon Arm

TRD

PHOS

PMD

ITS

TOF

TPC

Page 13: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft13

-6-4-3-2-101234 90o 180o 270o 360o

Rap id ity

Azimuth

FMD -5.4 < <-1.6-2.3<<-3.5

1.6<<32.4<<4

+++:-0.9<<0.9-2<<2

-.45<<0.45φ=57ο-.12<<0.12φ=100ο

-6

-4

-3

-2

-1

0

1

2

3

4

90o 180o 270o 360o

Rapidity

Azimuth

FMD -5.4 < <-1.6

PMD-2.3<<-3.5

FMD1.6<<3

Muonarm2.4<<4

ITS+TPC+TRD+TOF:-0.9<<0.9

ITSmultiplicity-2<<2

HMPID-.45<<0.45

φ=57ο

PHOS-.12<<0.12φ=100ο

ALICE ALICE AcceptanceAcceptance

central barrelcentral barrel -0.9 < -0.9 < < 0.9 < 0.9 tracking, PID single arm RICH (HMPID) single arm em. calo (PHOS)

forward muon armforward muon arm 2.4 < 2.4 < < 4 < 4 absorber, dipole magnettracking & trigger chambers

multiplicitymultiplicity -5.4 < -5.4 < < 3 < 3 including photon counting in PMD

trigger & timingtrigger & timing dets dets Zero Degree Calorimeters T0: ring of quartz window PMT's V0: ring of scint. Paddles

Page 14: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft14

ALICE CollaborationALICE Collaboration

UKPORTUGAL

JINR

GERMANY

SWEDENCZECH REP.

HUNGARYNORWAY

SLOVAKIA

POLANDNETHERLANDS

GREECE

DENMARKFINLAND

SWITZERLAND

RUSSIA CERN

FRANCE

MEXICOCROATIA ROMANIA

CHINA

USAARMENIA

UKRAINE

INDIA

ITALYS. KOREA

937 Members

(63% from CERN MS)

28 Countries

77 Institutes

0

200

400

600

800

1000

1200

1990 1992 1994 1996 1998 2000 2002 2004

ALICE Collaboration statistics

LoI

MoU

TP

TRD

Page 15: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft15

ALICE Technical BoardALICE Technical Board

Page 16: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft16

ALICE Design PhilosophyALICE Design Philosophy General Purpose Heavy Ion DetectorGeneral Purpose Heavy Ion Detector one single dedicated HI expt at LHC ATLAS/CMS have some interest, but priority is pp physics AGS/SPS: several (6-8) 'special purpose expts' RHIC: 2 large multipurpose + 2 small special purpose expts

cover essentially all known observables of interestcover essentially all known observables of interest comprehensive study of hadrons at midrapidity large acceptance, excellent tracking and PID

state-of-the-art measurement of direct photons excellent resolution & granularity em calo (small but expensive !)

dedicated & complementary systems for di-electrons and di-muons cover the complete spectrum: from soft (10's of MeV) to hard (100's of GeV) more recent design feature, still incomplete ...

stay open for changes & surprisesstay open for changes & surprises high throughput DAQ system + powerful online intelligence ('PC farm') flexible & scalable: minimum design prejudice on what will be most interesting

Page 17: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft17

Reality is more difficult..Reality is more difficult.. technical and financial constraints lead to compromisestechnical and financial constraints lead to compromises acceptance is limited to about y = 2 fragmentation region is not addressed in any case, difficult at LHC (beam rapidity = 9)

robust tracking <-> rate capability limited by pile-up in TPC to some 8 kHz in AA

no large area calorimeters at least, not yet…

Page 18: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft18

L3 magnetL3 magnet still largest magnetstill largest magnet magnet volume: 12 m long, 12 m high 0.5 T solenoidal field

Adding door plugsRemoving L3

Page 19: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft19

The ALICEThe ALICE Magnet: Magnet:

ready for the experiment to move in!ready for the experiment to move in!

Page 20: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft20

ALICE ALICE R&DR&D

Inner Tracking System (ITS)Inner Tracking System (ITS) Silicon Pixels (RD19) Silicon Drift (INFN/SDI) Silicon Strips (double sided) low mass, high density interconnects low mass support/cooling

TPC TPC gas mixtures (RD32) new r/o plane structures advanced digital electronics low mass field cage

em calorimeterem calorimeter new scint. crystals (RD18)

PIDPID Pestov Spark counters Parallel Plate Chambers Multigap RPC's (LAA) low cost PM's solid photocathode RICH (RD26)

DAQ & ComputingDAQ & Computing scalable architectures with COTS high perf. storage media GRID computing

miscmisc micro-channel plates rad hard quartz fiber calo. VLSI electronics

1990-1996:Strong, well organized, well funded R&D activity

• R&D made effective use of long (frustrating) wait for LHC• was vital for all LHC experiments to meet LHC challenge !

??

?

Page 21: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft21

Time of Flight DetectorsTime of Flight Detectors aim: state-of-the-art TOF at ~1/10 current price ! aim: state-of-the-art TOF at ~1/10 current price ! requirements: area > 150 m2, channels ~ 150,000, resolution < 100 ps existing solution: scintillator + PM, cost > 120 MSF ! R&D on cheaper fast PM's in Russia failed to deliver

gas TOF counters + VLSI FEEgas TOF counters + VLSI FEE Pestov Spark Counter (PSC)

100 m gap, > 5 kV HV, 12 bar, sophisticated gas < 50 ps, some 'tails' (?), but only (!) ~ 1/5 cost technology & materials VERY challenging

Parallel Plate Chamber (PPC) 1.2 mm gap, 1 bar, simple gas & materials 1/10 cost, but only = 250 ps unstable operation, small signal

Multigap Resistive Plate Chambers (MRPC) breakthrough end 1998 after > 5 years of R&D ! many small gaps (10x250 m), 1 bar, simple gas & materials ~ 1/10 cost, < 100 ps , simple construction & operation,..

Page 22: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft22

The RHIC connection..The RHIC connection.. already used at RHICalready used at RHIC HMPID 2 years sabbatical at STAR double sided SSD being installed @ STAR PMD ALICE copy @ STAR ROOT (offline) all 4 expts

concrete upgrade plansconcrete upgrade plans TOF MRPC finally, a 2 TOF for STAR... TPC FEE replace existing FEE in STAR silicon pixels SPD PHENIX, fallback for STAR

of potential interest ..of potential interest .. high resolution PbW04 calo PHENIX ? TRD test module PHOBOS ??? high bandwidth DAQ ?? distributed GRID computing ??

Page 23: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft23

Inner Tracking System (ITS)Inner Tracking System (ITS)

6 Layers, three technologies 6 Layers, three technologies (keep occupancy ~constant (keep occupancy ~constant ~2% ~2% for max mult)for max mult)

Silicon Pixels (0.2 m2, 9.8 Mchannels) Silicon Drift (1.3 m2, 133 kchannels) Double-sided Strip Strip (4.9 m2, 2.6 Mchannels)

Rout=43.6 cm

Lout=97.6 cm

SPD

SSD

SDD

Major technological challenge!Material Budget: < 1% X0 per layer !

Page 24: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft24

ITS Electronics DevelopmentsITS Electronics Developments(all full-custom designs in rad. tol., 0.25 (all full-custom designs in rad. tol., 0.25 m process)m process)

Pre

ampl

ifie

rs

Analoguememory

AD

Cs

ALICE PIXEL CHIP50 µm x 425 µm pixels 8192 cells Area: 12.8 x 13.6 mm2

13 million transistors ~100 µW/channel

ALICE SDD FEEPascal chip:64 channel preamp+ 256-deep analogue memory+ ADC Ambra chip:64 channel derandomizer chip

ALICE SSD FEEHAL25 chip:128 channelsPreamp+s/h+ serial out

And extreme lightweight interconnection techniques:

SSD tab-bondable Al hybrids

Page 25: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft25

System testing and setting up of series System testing and setting up of series productionproduction

Pixel ladder Strip moduleassembly

Drift cooling system

Page 26: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft26

ITS Support Acceptance TestITS Support Acceptance Test

Deformation < 200 m under load of 1 kg

Page 27: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft27

25 µm aluminized Mylar on Al frameCentral Electrode PrototypeCentral Electrode Prototype

~ 3 m diameter

drift gas90% Ne - 10%CO2

Field Cage Inner Vessel

TPTPCC

largest everlargest ever 88 m3, 570 k channels

Page 28: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft28

TPC Field TPC Field CageCage

Page 29: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft29

TPC R/O chambersTPC R/O chambers

~ 1/2 of inner R/O chambers ~ 1/2 of inner R/O chambers readyready

Page 30: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft30

TPC: TPC: ElectronicsElectronics

STAR/NA49: STAR/NA49: precise tail cancellation, analogue storage, digital processing off det. precise tail cancellation, analogue storage, digital processing off det. ALICE: ALICE: simple shaping, fast ADC, digital shaping & filtering on detectorsimple shaping, fast ADC, digital shaping & filtering on detector

ALTRO: ALTRO: commercial ADC integrated with custom digital chip: commercial ADC integrated with custom digital chip: SoCSoC 0.25 micron technology (ST), 64 mm2, 29 mW/ch, SEU protection System-on-Chip challenge: integrate analogue & digital functions w/o degradation of performance !

anode wire

pad plane

drift region88s

L1: 5s 200 Hz

PASA ADC DigitalCircuit

RAM

8 CHIPS x

16 CH / CHIP

8 CHIPSx

16 CH / CHIP

CUSTOM IC(CMOS 0.35m) CUSTOM IC (CMOS 0.25m )

DETECTOR FEC (Front End Card) - 128 CHANNELS(CLOSE TO THE READOUT PLANE)

FEC (Front End Card) - 128 CHANNELS(CLOSE TO THE READOUT PLANE)

570132PADS

1 MIP = 4.8 fC

S/N = 30 : 1

DYNAMIC = 30 MIP

CSA SEMI-GAUSS. SHAPER

GAIN = 12 mV / fCFWHM = 190 ns

10 BIT

< 10 MHz

• BASELINE CORR.

• TAIL CANCELL.

• ZERO SUPPR.

MULTI-EVENT

MEMORY

L2: < 100 s 200 Hz

DDL(4096 CH / DDL)

Powerconsumption:

< 40 mW / channel

Powerconsumption:

< 40 mW / channel

gat

ing

gri

d

Page 31: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft31

ZERO SUPPRESSION THRESHOLD: 5 ADC COUNTS

TPC Electronics:TPC Electronics: ALALICE ICE TTPCE PCE RREADEADOOUT CHIPUT CHIP (ALTRO)(ALTRO)

AdaptiveBaselineCorrect.

I

AdaptiveBaselineCorrect.

I

ADCADC TailCancel.

TailCancel.

DataFormat.

DataFormat.

Multi-EventMemory

AdaptiveBaselineCorrect.

II

AdaptiveBaselineCorrect.

II

+-

10- bit20 MSPS

11- bit CA2arithmetic

18- bit CA2arithmetic

11- bitarithmetic

40-bitformat

40-bitformat

ALTRO OUTPUTFILTER DISABLED

ALTRO OUTPUTFILTER ENABLED

THE TEST INPUT SIGNAL IS A CONVOLUTION OF

THE SIGNAL MEASURED ON THE TPC PROTOTYPE

WITH THE AMPLITUTE AND ARRIVAL TIME

DISTRIBUTIONS GENERATED BY ALIROOT

ALTROtest result

Page 32: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft32

ALTRO: Better-Smaller-ALTRO: Better-Smaller-CheaperCheaper

4cards16 ch

13

5 m

m

1998channels per chip: 1

ADC: 1 externalDigital Filter: no

1999channels per chip: 4

ADC: 4 externalDigital Filter: no

2001channels per chip: 16

ADC: 16 internalDigital Filter: yes

Integrated ADCs

20

mm

4 PQFP 100

8 SSOP 28

24 mm

Under discussion for STAR TPC !

DIGITAL PROCESSOR & CONTROL LOGIC

8 A

DC

s 8 A

DC

s

ME

MO

RY

Page 33: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft33

Tracking ChallengeTracking Challenge

STARSTAR

NA49 ALICE 'worst case' scenario:

dN/dych = 8000

Page 34: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft34

TrackinTrackingg robust, redundant tracking from 60 MeV to 100 GeVrobust, redundant tracking from 60 MeV to 100 GeV

modest soleniodal field (0.5 T) => easy pattern recognition long lever arm => good momentum resolution silicon vertex detector (ITS) 4 cm < r < 44 cm stand-alone tracking at low pt

Time Projection Chamber (TPC) 90 cm < r < 250 cm Transition Radiation Detector (TRD) 290 cm < 370 cm

p/p (%) for B=0.4T TPC+ITS

TPC+ITS+TRDTracking efficiency in TPC vs. multiplicty

p/p ~ 16% at 100 GeV

(~ 11% at dN/d = 2000)

Page 35: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft35

Vertex FindingVertex Finding little material + good resolution + close to vertexlittle material + good resolution + close to vertex primary vertex: 15 m (r) x 5 m (z)

secondary vertices: heavy quarks (100's m) hyperons (cm)

ITS Primary vertex

d0 < cut resonancesd0 > cut D,B mesons

impact parameter d0 (r)

Page 36: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft36

stable hadrons (stable hadrons (, K, p): 100 MeV < p < 5 GeV, K, p): 100 MeV < p < 5 GeV dE/dx in silicon (ITS) and gas (TPC) + Time-of-Flight (TOF) + Cerenkov (RICH) dE/dx relativistic rise under study => extend PID to several 10 GeV ??

decay topology (Kdecay topology (K00, K, K++, K, K--, , )) still under study, but expect K and decays up to at least 10 GeV

leptons (e, leptons (e, ), photons, ), photons, 00

electrons in TRD: p > 1 GeV muons: p > 5 GeV 0 in PHOS: 1 < p < 80 GeV

Particle IdentificationParticle Identification

0 1 2 3 4 5 p (GeV/c)

1 10 100 p (GeV/c)

TRD e / PHOS /0

TPC + ITS (dE/dx)

/K

/K

/K

K/p

K/p

K/p

e /

e /

HMPID (RICH)

TOF

Alice uses ~ all known techniques!

Page 37: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

RIKEN 10/2002 J. Schukraft37

DOUBLE STACK OF 0.5 mm GLASS

Edge of active area

cathode pick up pad

cathode pick up pad

anode pick up pad

Resistive layer (cathode)

Resistive layer (cathode)

Resistive layer (anode)

Resistive layer (anode)

5 gaps

5 gaps

160 m2, 160 k channelsr = 3.7 m, < 100 ps

for , K, p PID , K for p <2 GeV/cp for p <4 GeV/c

full size TOF modules under test

Multigap Resistive Plate Chambers

Time Of FlightTime Of Flight

96 readout pads per

strip

Page 38: Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion Physics at LHC LHC machine LHC machine ALICE ALICE  Collaboration.

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TOF Test ResultsTOF Test Results

0 500 1000-500-1000

1200

1000

800

600

400

200

0

STRIP 10 H.V. +- 6 kV

Time with respect to timing scintillators [ps]

= 53 ps minus 30 ps jitter

of timing scintillator = 44 ps

Entries/50 ps

404550556065707580

5.0 5.5 6.0 6.5

0

20

40

60

80

100

5.0 5.5 6.0 6.5

Efficiency [%]

Applied voltage [kV]Resolution [ps]

strip 12strip 10

Applied voltage [kV]

strip 12strip 10

Typical performance

Typical time spectrum

other expts using ALICE MRPC technologyother expts using ALICE MRPC technology HARP @ CERN (expt. finished) STAR @ RHIC (proposal) FOPI @ GSI (planning)

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7 modules, each ~1.5 x 1.5 m2

STAR data

RICH

High Momentum Particle IdentificationHigh Momentum Particle Identification

First Modulein production

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HMPID Proto-2: Excursion to BNLHMPID Proto-2: Excursion to BNL

Proto-2 @ CERN, tested in 1997

Arrival at BNL, August 1999 Into STAR, November 1999

July 2002: Back home again

STAR datapions

kaons

protons

p > 1 GeV

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ITS

TPC

TOF

Particle Identification performanceParticle Identification performance

HMPID

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dE/dx relativistic dE/dx relativistic rise ?rise ?

combine TPC and TRD dE/dx capabilitiescombine TPC and TRD dE/dx capabilities pion ID up to several 10 GeV ? K/p on a statistical basis ?

8<p<10GeV/c

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Photons & LeptonsPhotons & Leptons PhotonsPhotons LHC: high particle density + large combinatorial background for 0, high granularity => dense material + large distance from vertex good resolution => scintillation crystals

compromise: acceptance ( ok for -> @ 1GeV)

MuonsMuons classical muon spectrometer (NA50, Phenix) high performance chambers: ~ 106 channels, very thin, small dead area goal: m/m ~ 1% @ 10 GeV (separate Y'')

challenge: integrate with central barrel ! very complex & sophisticated absorbers

Electrons Electrons (later addition to ALICE)(later addition to ALICE) combine TPC tracking with e-ID: Transition radiation detector TRD large area (800 m2) , high granularity (> 106 channels) challenge: triggering on high pt electrons

requires on-line tracking in < 6 s !!!

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for photons, neutral mesons and -jet tagging

PbW04: Very dense: X0 < 0.9 cmGood energy resolution (after 6 years R&D):stochastic 2.7%/E1/2

noise 2.5%/Econstant 1.3%

Photon SpectrometerPhoton Spectrometer

PbW04 crystal

single arm em calorimetersingle arm em calorimeter dense, high granularity crystals novel material: PbW04

~ 18 k channels, ~ 8 m2

cooled to -25o

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PHOSPHOS mass production of crystals startedmass production of crystals started Apatity, Russia

Light Read-out Light Read-out APD's (Avalanche Photo Diodes) FEE still in design phase

PHOS 256-Channel Prototype

Collaboration:- Russia + Norway- China (tbc)Needs strengthening !

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• identify & trigger on electrons• used also in tracking• trigger on jets (high pt hardons)

largest chamber: 1200 x 1600 mm

Full scale prototype

currently ~ 60% funded

Transition Radiation DetectorTransition Radiation Detector

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Dimuon SpectrometerDimuon Spectrometer Study the production of the J/Study the production of the J/, , ', ', , , ' and ' and

'’ decaying in 2 muons, '’ decaying in 2 muons, 2.4 <2.4 < < 4 < 4 Resolution of 70 MeV at the J/Resolution of 70 MeV at the J/ and 100 MeV and 100 MeV

at the at the

Dipole Magnet: bending power 3Tm

Complex absorber/small angle shield system to minimize background(90 cm from vertex)

RPC Trigger Chambers

5 stations of high granularity pad tracking chambers, over 800k channels

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Muon ChambersMuon Chambers Station 3-4: Slats

Trigger RPC

Station 1&2: Quadrants

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Muon MagnetMuon Magnet Dipole Magnet Dipole Magnet 0.7 T and 3 Tm 4 MW power, 800 tons World’s largest warm dipole

Progress:Progress: Coil production in progress in France Yoke finished end 2002 in Russia

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Proposed EMCAL||<0.7 ~ 120o

US proposal: large emcalUS proposal: large emcal large area electromagnetic calorimeter (a la STAR)large area electromagnetic calorimeter (a la STAR) hadronic energy in TPC + em energy in calorimeter trigger on jets, improve energy resolution, -jet coincidences (with PHOS)

(PT) ~15%

100 GeV Jet in Central PbPb

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T0L

Forward Forward DetectorsDetectors

V0 1.6 < |< 3.9 Interaction trigger (beam-gas rejection), centrality trigger and beam-gas rejection. Two arrays of 72 scintillator tiles readout via fibers

T0R 2.6 < || < 3.3 measure

event Time (T0) for the TOF (~

50 ps time res.) Two arrays of 12 quartz counters. Also backup to V0

FMD Measure Multiplicity and dist. over 1.6 < < 3, -5.4 < < -1.6 Silicon pad detector disks (slow readout) with 12k analog channels (occ.>1)

PMD pre-shower detector

2.3 < < 3.5, measures ncharged and nphotons

(DCC's)

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PMD for STARPMD for STAR

• STAR-PMD design is identical to ALICE-PMD TDR version• Fabrication mostly done – lab testing in progress• being installed – will be complete by Nov 2002

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Zero Degree Zero Degree CalorimeterCalorimeter

ZN

ZP

Proton

ZDC (ZP) Neutron

ZDC (ZN) EM

ZDC

Dimensions (cm3)

12x21x150 7x7x100 7x7x21

Absorber brass W-alloy lead

Fibre angle wrt LHC axis

0O 0O 45O

Fibre ∅(m) 550 365 550

First ZDC finished

6 small & dense calorimeters6 small & dense calorimeters trigger on impact parameter (spectators) located between 8m (em calo) and 116 m (ZP, ZN) from IP

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High Level Trigger High Level Trigger (HLT)(HLT)

online PC farmonline PC farm FPGA co-processors in RORC ~ 500 - 600 dual CPU PC’s ~300 LDC’s (DAQ+HLT)~ 300 dedicated PC’s

test clusters running (Heidelberg, Oslo, Bergen) FPGA algorithm development

Task: BE FLEXIBLE !Task: BE FLEXIBLE ! selective R/O (RoI, eg e+e- pairs) event selection high mass lepton pairs (e, ) jets (high pt tracks)

data compression factor 2 to > 10 with online tracking in TPC

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ALICE DC III

Computing Phase Computing Phase TransitionTransition

Online:Online: storing up to 1.2 Gbyte/s storing up to 1.2 Gbyte/s whole WWW in few hours on tape ! ~ 10 x RHIC !

Offline:Offline: 1800 kSI95 1800 kSI95 300,000 PC's in 2000 (500 Mhz) ~ 100 x RHIC !!

The Problem:

The Answer:

cheap mass market componentscheap mass market components Industry & Moore's law

The Challenge:

make 10,000 mice do the make 10,000 mice do the

work of one elephantwork of one elephant

new computing paradigm: The GRID

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Performance Monitoring

ALICE Data ChallengesALICE Data Challenges

Regional TIER 1 TIER 2

DAQ

Simulated Data

ROOT I/OCERN TIER 0 TIER 1

Raw Data

GEANT3GEANT4FLUKA

AliRoot

CASTOR

GRID

ROOT

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ADC ADC Performance/plans:Performance/plans:

0

50

100

150

200

250

300

350

1999 2000 2001

DAQ

Mass Storage (sust)

Mass Storage (peak)

MB

/s

0

500

1000

1500

2000

2500

3000

1999 2000 2001 2002 2003 2004 2005 2006

DAQ

Mass Storage

MB

/s

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2002: ADC IV Hardware Setup2002: ADC IV Hardware Setup

2 2 23 3 3 3

3 3 3 3

Total: Up to 192 CPU servers, Up to 36 DISK servers, 10 TAPE servers

2

10 TAPE servers(distributed)

CERN Backbone(4 Gbps)

8

TOTAL: 32 ports TOTAL: 18 ports

CPU servers on FE

TBED00 01-12 13-24 25-36 37-48

49-60 61-72 73-77

01D-12D13D-24D25D-36DLXSHARE

4 Gigabit switches 3 Gigabit switches

4 Gigabit switches

20 DISK serversCPU servers on GE

CPU servers on GE

90-100

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ADC IV ADC IV performancesperformances

DATE event-building

1.8 Gbytes/s:

target 1 Gbyte/s

Data recording to disk

350 MBytes/s.

target 300 MBytes/s

Outperforming the plan, with commodity hardware!

In stable operation

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ADC II (2000)ADC II (2000)

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Yerevan

CERN

Saclay

Lyon

Dubna

Capetown, ZA

Birmingham

Cagliari

NIKHEF

GSI

Catania

BolognaTorino

Padova

IRB

Kolkata, India

OSU/OSCLBL/NERSC

Merida

Bari

The CORE GRID functionality existsThe CORE GRID functionality exists Distributed production in action for the PPRDistributed production in action for the PPR

ALICE GRID is there: ALICE GRID is there: ALIENALIEN

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Production StatusProduction StatusTotal jobs per site

42%

15%

17%

5%

6%

1%

8%

2%4% 0%0%0%

0%

0%

CERN

Torino

LBL

Lyon

Catania

OSC

FZK

Padova

CNAF

GSI

Utrecht

Zagreb

Budapest

Prague

ALICE Productions

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

2001-02 2002-02 2002-03 2002-04

CPU

15100 jobs,~12CPUh/job, ~1GB output/job

up to 450 concurrently running

jobs

Number of concurrent jobs

0

50

100

150

200

250

300

350

400

450

500

2001-02 2002-02 2002-03 2002-04

Production round

#of jobs

Series1

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Hadronic Observables IHadronic Observables Iparticle spectra (single event) two particle HBT correlations

multiplicity, pseudorapidity reconstructionreaction plane resolution

multiplicity in ALICE central detector

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Hadronic Observables IIHadronic Observables II

K+K

p

K0 +-

Reconstruct (dN/dy~6k): ~

30 K0/central event ~ 3 /central event

p,K,K*, , D, d, T, , ..

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Heavy Heavy QuarksQuarks

Hadronic charm: D -> KHadronic charm: D -> K uses sec. vertex & PID acceptance to ~ 0 pt => tot

full kinematic reconstruction => 'quark quenching'

under study: D*, D, Bc, b, ...

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QuarkoniaQuarkonia

Acceptance Acceptance down to pt = 0

J/

J/

+-

e+e-

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Di-MuonsDi-Muons

• M =94.5 MeV/c2

at the • Separation of , ’, “• Total efficiency ~ 75%• Expected statistics (significance – 1 yr): central min. bias J/ 310 574 ’ 12 23 39 69 ‘ 19 35 “ 12 22from min. bias events:~ 8k and ~700k J/ /yr

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Jet QuenchingJet Quenching jet quenching = energy loss of leading particlejet quenching = energy loss of leading particle lost energy appears in soft particles => change of jet fragmentation function ! total jet-energy does not change ! => calorimeter only is insufficient

30-50 GeV 50-80 GeV

120-170 GeV

230-330 GeV

440-600 GeV

80-120 GeV

170-230 GeV

330-440 GeV

0 < pT < 50 GeV/c

Jet fragment pT distribution in jet cone

Normalized background pT distribution in jet cone

ALICE handles on jet quenchingALICE handles on jet quenching leading hadrons inclusive pt spectra & correlations identified hardons (, 0, , K)

leading heavy quarks inclusive b, c, D, B b, c tagging in jets (high pt electrons in TRD)

jet fragmentation function (TPC,TRD,emcal) correlations -jet (PHOS-emcal) jet1(emcal)-jet2(TPC)

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SummarSummaryy

LHC is the LHC is the ultimate machineultimate machine for Heavy Ion Collisions for Heavy Ion Collisions very significant step beyond RHIC excellent conditions for experiment & theory (QCD) not only latest, but possibly last HIC at the energy frontier

ALICE is a powerful ALICE is a powerful next generation detectornext generation detector first truly general purpose HI experiment addresses most relevant observables: from super-soft to ultra-hard

many evolutionary developments SSD, SDD, TPC, em cal, …

some big advances in technology electronics, pixels, TOF, computing

Heavy Ion Community can look forward toeventually

exploit this unique combination !


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