Heavy Ions @ LHC Heavy Ion Physics at LHC LHC machine ALICECollaborationDetectorPerformance

Physics@LHC: Caveat long 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 RHIC some expectations turned out right: SPS: strangeness enhancementRHIC: particle ratios, jet-quenching(?) some turned out wrong: SPS: large E-by-E fluctuationsRHIC: multiplicity dN/dy a number of unexpected surprises: SPS: J/Psi suppressionRHIC: elliptic flow, 'HBT-puzzle' lesson when preparing ALICE at LHC guided by theory and expectations, but stay open minded ! 'conventional wisdom' soft physics: smooth extrapolation of SPS/RHIC necessary, but boring ??? hard physics: new domain at LHC

Hard Probes @ LHC 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 GeVX 2000

Jets in ALICE |h| 100 GeV/creal jets triggers 0.7/sfalse triggers 0.3/sPb Pb rates:ppL = 1030cm-2s-1 ideal energy for jet-quenching: around 100 GeV pQCD applicable jets measurable above soft background energy loss still relatively large effect DE/E ~ O(10%), decreasing with E !

Heavy Quarks & Quarkonia copious 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 ds/dy LHC ~ 20 x RHIC Y will probably need higher Lumi at RHIC even at LHC Y'' is difficult

What multiplicity do we expect? old estimates: dNch/dy 2000 - 8000, can we extrapolate from RHIC data ? few hundred per month(from K.Kajantie, K.Eskola)dNch/dh ~ 2500

Initial Conditions my pre-RHIC guess (QM2001) still expect conditions to be significantly different only LHC will give the final answer !Significant gain in e, V, t x 10 SPS -> LHC x 3-5 RHIC -> LHC

The Soft StuffFreeze-out Hyper surfaceSPSLHC changes 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 ~ #particlesAGSRHICLHC ?Biggest surprise would be none..

LHC Status the long & winding road to LHC first discussion on HI in LHC: 1990 LHC approved 1994 /1996 start-up several times postponed CERN financial problems some 20% cost overrun (~800 MCHF) solution in sight reduce non- LHC program, bank loans, savings, 1 year delay machine well into construction civil engineering almost finished ~ 20 production magnets tested LHC start-up: April 2007 first short heavy ion run: end 2007External Machine Review Committee: 'Tight, but feasible'Atlas cavern

LHC MagnetsMain DipoleTransfer LinesMQWInsertion (Japan)

Heavy Ions in LHC energy Ebeam = 7 x Z/A [TeV] s = 5.5 TeV/A (Pb-Pb), 14 TeV (pp) beams 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 low L runs: avoid pile-up in TPC high L runs: max rate in muon arm

Pb-Pb

Ar-Ar

pp

L [cm-2s-1]

1027

3x1027 to 1029

1029 to 3x1030

Rate [kHz]

8

8 to 250

7 to 200

ALICE Set-upHMPIDMuon ArmTRDPHOSPMDITSTOFTPC

ALICE Acceptance central barrel -0.9 < h < 0.9 tracking, PID single arm RICH (HMPID) single arm em. calo (PHOS) forward muon arm 2.4 < h < 4 absorber, dipole magnet tracking & trigger chambers multiplicity -5.4 < h < 3 including photon counting in PMD trigger & timing dets Zero Degree Calorimeters T0: ring of quartz window PMT's V0: ring of scint. Paddles

ALICE Collaboration937Members (63% from CERN MS)28Countries77Institutes

pie

157

89

74

105

28

28

18

11

15

12

8

8

12

8

8

5

4

112

69

55

20

11

11

30

12

7

7

13

Sheet1

MemberITALYFRANCECERNGERMANYSLOVAKIAPOLANDCZECH REP.HUNGARYNORWAYSWEDENPORTUGALUKNETHERLANDSGREECEDENMARKFINLANDSWITZERLAND

States

5237434141171131248125854

13104141011741

42614752

331017

10825

71211

4

12

5

11

15

38

TOTAL157897410528281811151288128854590

Non-memberRUSSIAJINRINDIAUKRAINEUSAARMENIACHINAMEXICOCROATIAROMANIAS. KOREA

States

116968711812379

14774444

1716518

1911

34

22

119

15

20

TOTAL112695520111130127713347

Total Membership937

ALICE Technical Board

ALICE Design Philosophy General 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 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 & surprises high throughput DAQ system + powerful online intelligence ('PC farm') flexible & scalable: minimum design prejudice on what will be most interesting

Reality is more difficult.. technical and financial constraints lead to compromises acceptance is limited to about Dy = 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

L3 magnet still largest magnet magnet volume: 12 m long, 12 m high 0.5 T solenoidal fieldAdding door plugsRemoving L3

The ALICE Magnet:

ready for the experiment to move in!

ALICE R&D 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 gas mixtures (RD32) new r/o plane structures advanced digital electronics low mass field cage em calorimeter new scint. crystals (RD18)

PID Pestov Spark counters Parallel Plate Chambers Multigap RPC's (LAA) low cost PM's solid photocathode RICH (RD26) DAQ & Computing scalable architectures with COTS high perf. storage media GRID computing misc micro-channel plates rad hard quartz fiber calo. VLSI electronics1990-1996: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 !

Time of Flight Detectors aim: state-of-the-art TOF at ~1/10 current price ! requirements: area > 150 m2, channels ~ 150,000, resolution s < 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 FEE Pestov Spark Counter (PSC) 100 mm gap, > 5 kV HV, 12 bar, sophisticated gas s < 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 s = 250 ps unstable operation, small signal Multigap Resistive Plate Chambers (MRPC) breakthrough end 1998 after > 5 years of R&D ! many small gaps (10x250 mm), 1 bar, simple gas & materials ~ 1/10 cost, s < 100 ps , simple construction & operation,..

The RHIC connection.. already 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 plans TOF MRPCfinally, a 2p TOF for STAR... TPC FEE replace existing FEE in STAR silicon pixels SPD PHENIX, fallback for STAR of potential interest .. high resolution PbW04 caloPHENIX ? TRD test modulePHOBOS ??? high bandwidth DAQ?? distributed GRID computing??

Inner Tracking System (ITS) 6 Layers, three technologies (keep occupancy ~constant ~2% 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 cmLout=97.6 cmSPDSSDSDDMajor technological challenge!Material Budget: < 1% X0 per layer !

ITS Electronics Developments(all full-custom designs in rad. tol., 0.25 mm process)ALICE PIXEL CHIP50 m x 425 m pixels 8192 cells Area: 12.8 x 13.6 mm213 million transistors ~100 W/channelALICE 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 outAnd extreme lightweight interconnection techniques:SSD tab-bondable Al hybrids

System testing and setting up of series productionPixel ladder Strip moduleassemblyDrift cooling system

ITS Support Acceptance TestDeformation < 200 mm under load of 1 kg

25 m aluminized Mylar on Al frameCentral Electrode Prototype~ 3 m diameterdrift gas90% Ne - 10%CO2Field Cage Inner VesselTPC largest ever 88 m3, 570 k channels

TPC Field Cage

TPC R/O chambers ~ 1/2 of inner R/O chambers ready

TPC: Electronics STAR/NA49: precise tail cancellation, analogue storage, digital processing off det. ALICE: simple shaping, fast ADC, digital shaping & filtering on detector ALTRO: commercial ADC integrated with custom digital chip: SoC 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 wirepad planedrift region88msL1: 5ms 200 HzPASAADCRAM8 CHIPS x16 CH / CHIP

8 CHIPSx 16 CH / CHIPCUSTOM IC(CMOS 0.35mm)CUSTOM IC (CMOS 0.25mm )DETECTOR

FEC (Front End Card) - 128 CHANNELS(CLOSE TO THE READOUT PLANE)570132PADS1 MIP = 4.8 fCS/N = 30 : 1DYNAMIC = 30 MIPCSA SEMI-GAUSS. SHAPERGAIN = 12 mV / fCFWHM = 190 ns10 BIT< 10 MHz BASELINE CORR. TAIL CANCELL. ZERO SUPPR.MULTI-EVENTMEMORYL2: < 100 ms 200 HzDDL(4096 CH / DDL)Powerconsumption:< 40 mW / channelgating grid

TPC Electronics: ALICE TPCE READOUT CHIP (ALTRO)ZERO SUPPRESSION THRESHOLD: 5 ADC COUNTSAdaptiveBaselineCorrect.IADCTailCancel.DataFormat.Multi-EventMemoryAdaptiveBaselineCorrect.II+-10- bit20 MSPS11- bit CA2arithmetic18- bit CA2arithmetic11- bitarithmetic40-bitformat40-bitformatALTRO OUTPUTFILTER DISABLEDALTRO OUTPUTFILTER ENABLEDTHE TEST INPUT SIGNAL IS A CONVOLUTION OF THE SIGNAL MEASURED ON THE TPC PROTOTYPEWITH THE AMPLITUTE AND ARRIVAL TIME DISTRIBUTIONS GENERATED BY ALIROOT ALTROtest result

ALTRO: Better-Smaller-Cheaper135 mm1998channels per chip: 1ADC: 1 externalDigital Filter: no1999channels per chip: 4ADC: 4 externalDigital Filter: no2001channels per chip: 16ADC: 16 internalDigital Filter: yesIntegrated ADCs24 mmUnder discussion for STAR TPC !

Tracking ChallengeNA49 ALICE 'worst case' scenario:dN/dych = 8000

Tracking robust, 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 cmTracking efficiency in TPC vs. multiplictyDp/p ~ 16% at 100 GeV(~ 11% at dN/dh = 2000)

Vertex Finding little material + good resolution + close to vertex primary vertex: 15 mm (rf) x 5 mm (z) secondary vertices: heavy quarks (100's mm) hyperons (cm)ITS Primary vertex d0 < cut resonancesd0 > cut D,B mesonsimpact parameter d0 (rf)

stable hadrons (p, 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 (K0, K+, K-, L) still under study, but expect K and L decays up to at least 10 GeV leptons (e, m), photons, p0 electrons in TRD: p > 1 GeV muons: p > 5 GeV p0 in PHOS: 1 < p < 80 GeVParticle Identification0 1 2 3 4 5 p (GeV/c) 1 10 100 p (GeV/c) TRD e /p PHOS g /p0TPC + ITS (dE/dx) p/Kp/Kp/KK/pK/pK/pe /pe /pHMPID (RICH)TOF

160 m2, 160 k channelsr = 3.7 m, s < 100 psfor p, K, p PID p, K for p

TOF Test Results05001000-500-1000120010008006004002000STRIP 10 H.V. +- 6 kVTime with respect to timing scintillators [ps]s = 53 ps minus 30 ps jitterof timing scintillator = 44 psEntries/50 psTypical performanceTypical time spectrum other expts using ALICE MRPC technology HARP @ CERN (expt. finished) STAR @ RHIC (proposal) FOPI @ GSI (planning)

7 modules, each ~1.5 x 1.5 m2STAR dataRICHHigh Momentum Particle IdentificationFirst Modulein production

HMPID Proto-2: Excursion to BNLProto-2 @ CERN, tested in 1997Arrival at BNL, August 1999Into STAR, November 1999July 2002: Back home again

ITSTPCTOFParticle Identification performanceHMPID

dE/dx relativistic rise ? combine TPC and TRD dE/dx capabilities pion ID up to several 10 GeV ? K/p on a statistical basis ? 8

Photons & Leptons Photons LHC: high particle density + large combinatorial background for p0, h high granularity => dense material + large distance from vertex good resolution => scintillation crystals compromise: acceptance ( ok for h -> gg @ 1GeV) Muons classical muon spectrometer (NA50, Phenix) high performance chambers: ~ 106 channels, very thin, small dead area goal: Dm/m ~ 1% @ 10 GeV (separate Y'') challenge: integrate with central barrel ! very complex & sophisticated absorbers Electrons (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 ms !!!

for photons, neutral mesons and -jet taggingPbW04: Very dense: X0 < 0.9 cmGood energy resolution (after 6 years R&D):stochastic 2.7%/E1/2noise 2.5%/Econstant 1.3%Photon Spectrometer single arm em calorimeter dense, high granularity crystals novel material: PbW04 ~ 18 k channels, ~ 8 m2 cooled to -25o

PHOS mass production of crystals started Apatity, Russia Light Read-out APD's (Avalanche Photo Diodes) FEE still in design phase PHOS 256-Channel PrototypeCollaboration:- Russia + Norway- China (tbc)Needs strengthening !

identify & trigger on electrons used also in tracking trigger on jets (high pt hardons)largest chamber: 1200 x 1600 mmFull scale prototypecurrently ~ 60% fundedTransition Radiation Detector

Dimuon SpectrometerStudy the production of the J/Y, Y', U, U' and U' decaying in 2 muons, 2.4

Muon ChambersStation 3-4: SlatsTrigger RPCStation 1&2: Quadrants

Muon Magnet Dipole Magnet 0.7 T and 3 Tm 4 MW power, 800 tons Worlds largest warm dipole Progress: Coil production in progress in France Yoke finished end 2002 in Russia

US proposal: large emcalProposed EMCAL|h|

T0LForward DetectorsV0 1.6 < |h| < 3.9 Interaction trigger (beam-gas rejection), centrality trigger and beam-gas rejection. Two arrays of 72 scintillator tiles readout via fibersT0R 2.6 < |h| < 3.3 measure event Time (T0) for the TOF (~ 50 ps time res.) Two arrays of 12 quartz counters. Also backup to V0FMD Measure Multiplicity and h dist. over 1.6 < h < 3, -5.4 < h < -1.6 Silicon pad detector disks (slow readout) with 12k analog channels (occ.>1)PMD pre-shower detector 2.3 < h < 3.5, measures ncharged and nphotons (DCC's)

PMD 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

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

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

High Level Trigger (HLT) online PC farm FPGA co-processors in RORC ~ 500 - 600 dual CPU PCs ~300 LDCs (DAQ+HLT)~ 300 dedicated PCs test clusters running (Heidelberg, Oslo, Bergen) FPGA algorithm development

Task: BE FLEXIBLE ! selective R/O (RoI, eg e+e- pairs) event selection high mass lepton pairs (e, m) jets (high pt tracks) data compression factor 2 to > 10 with online tracking in TPC

Computing Phase Transition Online: storing up to 1.2 Gbyte/s whole WWW in few hours on tape ! ~ 10 x RHIC ! Offline: 1800 kSI95 300,000 PC's in 2000 (500 Mhz) ~ 100 x RHIC !!The Problem:

ALICE Data ChallengesCASTORGRID

ADC Performance/plans:MB/sMB/s

2002: ADC IV Hardware Setup22233333333Total: Up to 192 CPU servers, Up to 36 DISK servers, 10 TAPE servers210 TAPE servers(distributed)CERN Backbone(4 Gbps)8TOTAL: 32 portsTOTAL: 18 portsCPU servers on FETBED0001-1213-2425-3637-4849-6061-7273-7701D-12D13D-24D25D-36DLXSHARE4 Gigabit switches3 Gigabit switches4 Gigabit switches20 DISK serversCPU servers on GECPU servers on GE90-100

ADC IV performancesDATE event-building1.8 Gbytes/s:target 1 Gbyte/s

Data recording to disk350 MBytes/s.target 300 MBytes/s

Outperforming the plan, with commodity hardware! In stable operation

ADC II (2000)

ALICE GRID is there: ALIENYerevanCERNSaclayLyonDubnaCapetown, ZABirminghamCagliariNIKHEFGSICataniaBolognaTorinoPadovaIRBKolkata, IndiaOSU/OSCLBL/NERSCMeridaBariThe CORE GRID functionality exists Distributed production in action for the PPR

Production Status15100 jobs,~12CPUh/job, ~1GB output/jobup to 450 concurrently running jobs

Chart1

0.4320.180.140.1210.1070.0100000000

0.2880.1320.13700.03400.220.0810.0740.0160.010.00500

0.4590.1340.2100.0250.0180.0610.0250.06500.0010.00050.0010.0005

0.420.0470.160.0010.06200.270.010.010.0010.01000

CERN

Torino

LBL

Lyon

Catania

OSC

FZK

Padova

CNAF

GSI

Utrecht

Zagreb

Budapest

Prague

production round

CPU

ALICE Productions

Chart3

6302.904

2195.787

2525.54

702.638

925.441

155.53

1270.89

374.31

571.51

46.001

45.43

16.71

5.42

2.71

Total jobs per site

Sheet1

5797280054201201

2001-022002-022002-032002-04

CERN43.2%28.8%45.9%42.0%CERN6303

Torino18.0%13.2%13.4%4.7%Torino2196

LBL14.0%13.7%21.0%16.0%LBL2526

Lyon12.1%0.0%0.0%0.1%Lyon703

Catania10.7%3.4%2.5%6.2%Catania925

OSC1.0%0.0%1.8%0.0%OSC156

FZK0.0%22.0%6.1%27.0%FZK1271

Padova0.0%8.1%2.5%1.0%Padova374

CNAF0.0%7.4%6.5%1.0%CNAF572

GSI0.0%1.6%0.0%0.1%GSI46

Utrecht0.0%1.0%0.1%1.0%Utrecht45

Zagreb0.0%0.5%0.1%0.0%Zagreb17

Budapest0.0%0.0%0.1%0.0%Budapest5

Prague0.0%0.0%0.1%0.0%Prague3

Sheet2

Sheet3

Chart1

0.4320.180.140.1210.1070.0100000000

0.2880.1320.13700.03400.220.0810.0740.0160.010.00500

0.4590.1340.2100.0250.0180.0610.0250.06500.0010.00050.0010.0005

0.420.0470.160.0010.06200.270.010.010.0010.01000

CERN

Torino

LBL

Lyon

Catania

OSC

FZK

Padova

CNAF

GSI

Utrecht

Zagreb

Budapest

Prague

CPU

ALICE Productions

Chart3

6302.904

2195.787

2525.54

702.638

925.441

155.53

1270.89

374.31

571.51

46.001

45.43

16.71

5.42

2.71

Total jobs per site

Sheet1

5797280054201201

2001-022002-022002-032002-04

CERN43.2%28.8%45.9%42.0%CERN6303

Torino18.0%13.2%13.4%4.7%Torino2196

LBL14.0%13.7%21.0%16.0%LBL2526

Lyon12.1%0.0%0.0%0.1%Lyon703

Catania10.7%3.4%2.5%6.2%Catania925

OSC1.0%0.0%1.8%0.0%OSC156

FZK0.0%22.0%6.1%27.0%FZK1271

Padova0.0%8.1%2.5%1.0%Padova374

CNAF0.0%7.4%6.5%1.0%CNAF572

GSI0.0%1.6%0.0%0.1%GSI46

Utrecht0.0%1.0%0.1%1.0%Utrecht45

Zagreb0.0%0.5%0.1%0.0%Zagreb17

Budapest0.0%0.0%0.1%0.0%Budapest5

Prague0.0%0.0%0.1%0.0%Prague3

Sheet2

Sheet3

Chart1

0.4320.180.140.1210.1070.0100000000

0.2880.1320.13700.03400.220.0810.0740.0160.010.00500

0.4590.1340.2100.0250.0180.0610.0250.06500.0010.00050.0010.0005

0.420.0470.160.0010.06200.270.010.010.0010.01000

CERN

Torino

LBL

Lyon

Catania

OSC

FZK

Padova

CNAF

GSI

Utrecht

Zagreb

Budapest

Prague

production round

CPU

ALICE Productions

Chart3

6302.904

2195.787

2525.54

702.638

925.441

155.53

1270.89

374.31

571.51

46.001

45.43

16.71

5.42

2.71

Total jobs per site

Chart2

200

100

200

450

Production round

#of jobs

Number of concurrent jobs

Sheet1

5797280054201201

2001-022002-022002-032002-04

200100200450

CERN43.2%28.8%45.9%42.0%CERN6303

Torino18.0%13.2%13.4%4.7%Torino2196

LBL14.0%13.7%21.0%16.0%LBL2526

Lyon12.1%0.0%0.0%0.1%Lyon703

Catania10.7%3.4%2.5%6.2%Catania925

OSC1.0%0.0%1.8%0.0%OSC156

FZK0.0%22.0%6.1%27.0%FZK1271

Padova0.0%8.1%2.5%1.0%Padova374

CNAF0.0%7.4%6.5%1.0%CNAF572

GSI0.0%1.6%0.0%0.1%GSI46

Utrecht0.0%1.0%0.1%1.0%Utrecht45

Zagreb0.0%0.5%0.1%0.0%Zagreb17

Budapest0.0%0.0%0.1%0.0%Budapest5

Prague0.0%0.0%0.1%0.0%Prague3

15141

Sheet2

Sheet3

Hadronic Observables Iparticle spectra (single event)two particle HBT correlationsmultiplicity, pseudorapidity reconstructionreaction plane resolution multiplicity in ALICE central detector

Hadronic Observables IIf K+KpK0 +-Reconstruct (dN/dy~6k): ~ 30 K0/central event ~ 3 L/central eventp,h,w,f,p,K,K*, L, X, W, D, d, T, a, ..

Heavy QuarksHadronic charm: D -> Kp uses sec. vertex & PID acceptance to ~ 0 pt => stot full kinematic reconstruction => 'quark quenching' under study: D*, D, Bc, Lb, ...

Quarkonia Acceptance down to pt = 0m+m-e+e-

Di-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

Jet Quenching jet 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 ALICE handles on jet quenching leading hadrons inclusive pt spectra & correlations identified hardons (p, p0, h, L, 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 g-jet (PHOS-emcal) jet1(emcal)-jet2(TPC)

Summary LHC is the ultimate machine 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 next 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, computingHeavy Ion Community can look forward toeventuallyexploit this unique combination !