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Riken, Nov. 2002 ALICE at LHC J. Schukraft1 Heavy Ions @ LHC Heavy Ion Physics at LHC Heavy Ion...

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Riken, Nov. 2002 ALICE at LHC J. Schukraft 1 Heavy Ions @ LHC Heavy Ions @ LHC Heavy Ion Heavy Ion Physics at LHC Physics at LHC LHC machine LHC machine ALICE ALICE Collaboration Detector Performance
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  • Heavy Ions @ LHC Heavy Ion Physics at LHC LHC machine ALICECollaborationDetectorPerformance

  • [email protected]: Caveat long distance QCD is difficult to predict Theory well known, not so its consequences or manifestation [email protected]: 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 !


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