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					                                                          Physics at ALICE
                                                     for the ALICE collaboration
                                                         Paul Kuijer, NIKHEF



          Detector status and performance
          Physics analyses pp
          Plans for PbPb




Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF                            1
                                                    Detector overview




                                           Data Acquisition (DAQ)       Optimized for PbPb collisions:
                                        Detector Control System (DCS)   •High granularity (dN/dy~8000)
                                            High level trigger (HLT)    •Minimized material
Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF                                              2
                                     Detector configuration 2010
       ITS, TPC, TOF, HMPID, MUON, V0, T0, FMD, PMD, ZDC (100%)
       TRD (7/18)
       EMCAL (4/12)
       PHOS (3/5)
       HLT (60%)
   full hadron and muon capabilities
   partial electron and photon




Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF            3
                                               ALICE Performance
             TPC acceptance = 90%



                      Low material budget low pt cut off

                                                                   Momentum resolution
                                                                    ~ 5% @ 100 GeV




Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF                                  4
                           Charged Particle Acceptance

                                                                                    SPD




                                                           • operating with fast multiplicity
                                                             trigger L0 from Silicon Pixels




                                                          FMD
        V0




Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF                                         5
                                       Trigger configuration 2010
         based on interaction trigger reading all detectors:
                  SPD (min bias) or V0-A or V0-C
                  at least one charged particle in 8 pseudorapidity units

         and single-muon trigger reading MUON, SPD, V0, FMD, ZDC :
                  single muon, low-pT threshold, in the muon arm in coincidence with
                      interaction trigger

         activated in coincidence with the BPTX beam pickups:
                  „bunch-crossing‟ with bunches from both sides
                  for control „bunch-crossing‟ with bunch from side A or C only
                  for control „bunch-crossing‟ with no bunches
         a fraction of „bunch-crossing‟ trigger (no condition on trigger detectors)
            for control
            to measure relative fractions of single- and double-diffractive events
         High multiplicity trigger from SPD
            Studying up to which multiplicity to go


         HLT in Mode B (no event rejection)
Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF                                 6
                                    Data taking since March 30th

 since February till end
 of March cosmic-ray
 data taking                                                        all triggers

      ~105 events
                                                                   interaction triggers


 pp run since
 March 30th 2010
                                                          muon triggers (x50)

  7 TeV
      >600x106 events
                                                              0.9 TeV
  0.9 TeV
      7x106 events
                                                                   TPC now
                                                                 running at 900
                                                                       Hz

Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF                                   7
                                                 Offline data processing
               Raw data registration                                                                              Raw data processing




                                                             LHC restart 30.3
                                                                                                         • Pass 1-6 completed for 0.9 and 2.36
          5TB                                                                                            TeV data
Volume




                                                                                                         • Pass 0 @T0 introduced for calibration
                                                                                                         • Pass 1 @T0 for 7 TeV data follows the
                                                                                                         data taking
                                                                                                         • Analysis train running weekly: QA,
                                                                                                         physics working groups organized
                                                                                                         analysis
                      16.3                                                      1.4


                                                                                                  Run processing – start immediately after
                                                                                                  RAW data transferred to CERN MSS
                         MC production
                                                                                                  •Average – 5 hours per job
                                                                                      Frequency




   Several production cycles for 0.9, 2.36                                                        •At 10 hours, 95% of the runs are processed
   and 7 TeV pp with various generators                                                           •At 15 hours, 99% of the runs are processed
   (Phytia, PHOJET) and conditions from
   real data taking
   HI productions starting
                                                                                                           5h           10h            15h
   Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF                                                                                         8
                                                             HLT, DAQ, DCS

                                                                                                      HLT – infrastructure
                                                                                                      and front-end nodes
                                                                                                      completed for PbPb

                                                                                                      computing nodes
                                                                                                      needs to upgrade

                                                            HLT vertex reconstruction
                                                            (used for LHC feedback)




                              HLT K0S
                                                          DAQ, DCS, ECS –
                              reconstruction
                                                          new Automatic Configuration Tool

                                                          Create and archive a set of known good configurations
                                                          Select from this set according to beam condition and physics program
                                                          Software wizard to configure all the detectors and online systems


Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF                                                                      9
                                          Inner Tracking System – SPD
     Fully installed – still problem with cooling (insufficient flow of cooling fluid)
     improvements: freon sub-cooling close to detector; flow-meters and pressure regulators on each line
     typically ≥ 80% of half-staves operational
     fraction of dead pixels (in active half-staves) ~1.2%
      2010 run
                                                          Full SPD         Inner layer           Outer layer
      Active HS (out of)                                       103 (120)          32 (40)               71(80)
      Dead pixels ( in active HS )                              1.18 %             0.6%                 1.45%

                  Alignment precision
                                                                               Vertex reconstruction precision

                                                                                  ALICE performance
                                                                                      April 2010
              s=16 mm/√2




Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF                                                          10
                                Inner Tracking System – SDD, SSD
SDD – 94% (3) and 91.5% (4) operational
improved calibration of drift velocity                                                ALICE performance
residuals ~ 60 mm (nominal 35 mm)                                                         April 2010


SSD – 138 half-ladders operational (96%)
alignment within ~ 20 mm

calibration of dE/dx for PID
ITS alignment: JINST 5 P03003 (2010)
                                                          M. Chojnacki, E. Biolcati




                                                 ALICE performance
                                                     April 2010




                                                                                                   s ~ 20 mm




Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF                                                        11
                                                Time-Projection Chamber
 Detector fully operational: 99.9% of all channels
 dE/dx resolution: < 5%
 momentum resolution: < 7% at 10 GeV
 working on distortion map: dp/p < 5% at 10 GeV

 read-out rate up to 1kHz
 J. Alme et al., ALICE TPC coll., Nucl. Instr. Meth. A (in print), arXiv:1001.1950

                                                                                     No vertex cut !


                                                                                                   p (GeV/c)




Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF                                                        12
                                           Transition-radiation detector
7 out of 18 supermodules installed
production on schedule –
will be adjusted according the length
of winter shutdown

installed supermodules aligned
with tracks

gain calibration with g→e+e- K0s→p+p-




Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF                    13
                                                      Time-of-flight detector

       Fully installed –
       95% channels operational

       Time resolution –
       close to nominal




                                                                      b


                                                          σTOF=σ/√2
                                                          = 88 ps




Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF                         14
                                             PHOS, EMCal, HMPID, PMD

      PHOS – 3 out 5 modules installed and working at
      operational temperature – 25 C
      calibration in progress

      EMcal – 4 out 12 modules installed
      calibration in progress
                                                                      HMPID – fully installed
      6 modules prepared for installation
                                                                      alignment and calibration
                                                                      in progress
      PMD – 90% of channels operational
                                   Hits Distribution
                      Preshower plane                     CPV plane


                                                                           p


                                                                                K    p



Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF                                           15
                                                          Muon detector

Fully installed – muon chambers 95% of
channels operational
stable operation, alignment not finalized yet

Trigger – 99% channels operational
stable operation, at L0 trigger on pt > 0.5 GeV




                                               trigger – track matching

                                                                          matching efficiency




Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF                                         16
       Amount of material measured with gamma conversions




Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF     17
                                                          Physics analyses
 5 papers published – accepted
        Charged-particle density in 900 GeV pp collisions
                  K. Aamodt et al. (ALICE), Eur. Phys. J C 65 (2010) 111
        Charged-particle multiplicity in 0.9 and 2.36 pp collisions
                  arXiv:1004.3034[hep-ph] accepted in Eur. Phys. J C
        Charged-particle multiplicity in 7 TeV pp collision – letter
                  arXiv:1004.3514[hep-ph] accepted in Eur. Phys. J C
        Measurement of antiproton/proton ratio in pp at 0.9 and 7 TeV
                  Phys.Rev.Lett Vol 105, No 7 (2010)
        Charged-particle transverse momentum spectra at 0.9 TeV
                http://arxiv.org/abs/1007.0719, Phys. Lett. B
 1 paper submitted
           Identical particle correlation in pp at 0.9 TeV
                http://arxiv.org/abs/1007.0516, Phys. Rev. D
 2 papers in draft
           Identified charged hadron spectra and yields in pp at 0.9 TeV
           Strange particle production in pp at 0.9 TeV
 Other analyses well underway
           High multiplicity pp events, azimuthal correlations, event structure, p0 spectra,
            charm production,...

Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF                                         18
                                                  dNch/dh versus √s
                  dNch/dh versus √s                                                                   Relative increase in dNch/dh
                                                Inelastic Nch ≥ 1 in |h|<1



                                                                     ALICE
                                                                     CMS
         NonSingleDiffractive
                                                                  all Inelastic
                                                                                                                  900GeV
                                                                                                                   7TeV
                                                                                                   900GeV
                                                                                                   2.36TeV
                             fits ~ s0.1




                                Results:
                                - dNch/dh well described by power law (√s)0.2
                                - increase with energy significantly stronger in data than MC’s
                                - Alice & CMS agree to within 1 s (< 3%)
Hot Matter-26/08/2010, ALICE physics, 2010, Karel Safarik, CERN
06/08/2010, ALICE @ ICHEP Paris P. Kuijer, NIKHEF                                 Overview of LHC physics                            19
                                       Multiplicity distribution
              Multiplicity distribution 900 GeV                                Multiplicity distribution 7 TeV




                                                                                                ALICE
                                                                                                CMS


   Results:
   - most of the ‘stronger increase’
                is in the tail of Nch
   - ALICE & CMS still agree perfectly !
Hot Matter-26/08/2010, ALICE physics, 2010, Karel Safarik, CERN
06/08/2010, ALICE @ ICHEP Paris P. Kuijer, NIKHEF                 Overview of LHC physics                        20
                     Momentum distribution 900 GeV
                           pT distribution                Comparison to MC’s
                                                            <pT> versus √s




 Results:
 - Finally some (slight) difference !
 - Spectrum seems to get harder towards midrapidity
 - MC’s have hard time to describe the full spectrum
Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF                        21
                                      <pT> versus multiplicity
                  pT for different multiplicities

                                                                                                         <pT> vs Nch




                                                                  Results:
                                                                  - Change concentrated at pt > 1 GeV (pQCD)
                                                                   (surprisingly little change below )
                                                                  - MC’s have hard time…
Hot Matter-26/08/2010, ALICE physics, 2010, Karel Safarik, CERN
06/08/2010, ALICE @ ICHEP Paris P. Kuijer, NIKHEF                   Overview of LHC physics                       22
                                                        MC scoreboard
                   MC/TUN             D6T                  Perugia0         CSC                      PHOJET
                      E                                                                                          MC << data
                                                                                                                 MC >> data
0.9 TeV




                   dNch/dh            -20%                    -17%          +3%                       -2%
                                                                                                                 MC ≈ data
                       Nch          Nch>10                    Nch>5          Nch>15                  Nch>10
                        pt                                                  pt>1GeV                   pt>1GeV
                      <pt>
7 TeV 2.36 TeV




                       h              -24%                     -21%        -2%                        -8%
                       Nch             Nch>1                       Nch>5   Nch >20                   Nch>15
                                         0
                        h             -27%                     -24%        -4%                        -17%
                       Nch                                                 Nch >30

                 Conclusion:
                 - none of the tested MC’s (adjusted at lower energy) does really well
                 - tuning one or two results is easy, getting everything right will require more effort
                  (and may, with some luck, actually teach us something on soft QCD rather than only turning knobs)

 Hot Matter-26/08/2010, ALICE physics, 2010, Karel Safarik, CERN
 06/08/2010, ALICE @ ICHEP Paris P. Kuijer, NIKHEF                         Overview of LHC physics                             23
                                                                                                                                23
                  Bose–Einstein correlations (HBT)
           QM enhancement of identical Bosons at small momentum difference
              enhancement of e.g. like-sign pions at low momentum difference qinv=|p1-p2|,
                               as function of multiplicity and pair momentum kT = |pT1+pT2|/2
              measure Space-Time evolution of the ‘dense matter’ system in heavy ions coll.
                  interpretation in ‘small systems’ (pp, e+e-) is less obvious..
              ‘enhancement’ rel. to phase-space and
                  any non-BE correlations (‘baseline’)            BE enhancement vs qINV
                  non-BE correlations important at high √(s) (‘minijets’)

                                             BE enhancement vs qINV
                                                                                           pp
                                                                      high multiplicity    Pb+Auunlike sign p+p-
                                                                      high momentum               high Nch, kT
                                                                                   radius ~ 1/width
                                          (Phojet)



                                         baseline


low multiplicity
low momentum kT
Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF                                                            24
                                                          HBT @ 900 GeV

                                                                      Source Radius vs pair momentum




                              Radius vs k                                   Using different Baselines
               Source Radius vs MultiplicityT



 Results:
- Radius increases with Nch, comparable to ISR, RHIC, TeV
- rather constant vs <kT> !
     sign. systematic uncertainty from ‘baseline’ shape
     dependence usually interpreted as sign of ‘flow’ in heavy ions
- neglecting non-BE correlations (‘flat baseline’)
  can cause kT dependence (at high √ s)!
Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF                                                 25
                                                     Baryon transport in pp
                                                                                  u            d
             u                d
                                           u              d                                J

                     u                                                                     u
                                                     u

                         Traditional                                            String Junction

     Baryon transport via the di-quark                          Baryon transport via di-quark, quark-J or
    Fragmentation function of di-quark                          Junction alone
 exponentially suppressed at large rapitity
                   gap                                          Different fragmentation functions
                                                                G.C. Rossi and G. Veneziano, Nucl
                                                                Phys. B123(1997)507
                                                                    exponentially suppressed, intercept
                                                                                                 (a -1)y
                                                                    model dependent P(y) ~ e      J




                                                                . Kopeliovich, Sov. J. Nucl. Phys. 45,
                                                                1078(1987)              P(y)  const
                                                                               
                                                                    Probability constant with rapidity

                   Large rapidity gap (9.6) at LHC  Difference in tails can be measured
                                                                       
                                                                                      26
Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF
                           Baryon – antibaryon asymmetry in pp


                                                                    Energy [TeV]                   0.9 TeV       7 TeV
                                                                       ALICE                 0.957 ± 0.006    0.991 ± 0.006
                                                                                             ± 0.014 (syst)   ± 0.014 (syst)
                                                                       ATLAS-CSC (306)              0.96           1.0
                                                           PYTHIA       Perugia-0 (320)             0.95           1.0
                                                                      Perugia-SOFT (322)            0.88          0.94
                                                                               ε=0                  0.98           1.0
                                                            QGSM       ε = 0.076, αJ = 0.5          0.96          0.99
                                                                       ε = 0.024, αJ = 0.9          0.89          0.95
                                                          HIJING-B                                  0.83          0.97



                                                               Ratio  most instrumental effects cancel

                                                          Hijing-B, Perugia-SOFT, QGSM(ε = 0.024, αJ = 0.9)
                                                                      incompattible with the data



                                                                                              27
Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF
                                                              Pbar/p ratio



                                                                                                                Little room for
                                                                                                                   additional
                                                                                          aJ  0.5 ( fixed)
                                                                p          1                                   stopping
                                                                          ( - )y
                                                                                         aP  1.2 ( fixed)
                                                                p  1+ C  e J P         C  10.0  1.0 
                                                                                                           



                                                          




                                                                                                         28
Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF
                    Identified particles (preliminary)
                                                                                                    Kaon pT distributions
                            Identified Particle pT                                                  stable & decays
                                    p K p


                                                     6 ways to measure Kaons …
                                                                             K→mn
                                                   p                         K0S → pp




                                                                  K   p

                          ITS dE/dx
                              TPC dE/dx
                                TOF




Hot Matter-26/08/2010, ALICE physics, 2010, Karel Safarik, CERN
06/08/2010, ALICE @ ICHEP Paris P. Kuijer, NIKHEF                         Overview of LHC physics                           29
                               Charged: p, K, p at 900 GeV




Hot Matter-26/08/2010, ALICE physics, 2010, Karel Safarik, CERN
06/08/2010, ALICE @ ICHEP Paris P. Kuijer, NIKHEF                 Overview of LHC physics   30
                        Decays: K0S, L, X, f at 900 GeV *


                       K0S → pp                                                      L→pp



                                                            Preliminary results:
                                                           - MC well below Data
                                                           - more so at high pT
                                                           - more so for L & X
                                                           - f ~ ok (at least some MC)



                 X+X→Lp                                                              f→KK




  2009 Data (~300 k events)
*Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF                                    31
                                                  L/K0S ratio 900 GeV
                                                          L/K0S Ratio in Au+Au at RHIC
                                                                                         |h| < 1
                                                              |y| < 0.75




                                                                                large Baryon/Meson ratio:
                                                                                parton coalescence from QGP ?




               - very good agreement between STAR (200 GeV) and ALICE (900 GeV)
               - very different from CDF (630/1800) and UA1 (630) for pT > 1.5 GeV
               - UA1(630) and CDF(630) don’t agree either …
               to be further investigated (different triggers, acceptance, feed-down correction ?)
Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF                                                         32
                             …and much more to come...
               S* → L p                                      K* → K p




                                                     W→LK   X→Lp




                                                                        < 2% of statistics
                                                                        at 7 TeV


Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF                                      33
                                     p0 and h from g conversion
                                                                   • e± identification in TPC (TRD soon)
                                                                   • study of g conversion points/material
                                                                     budget
                                                                  Raw π0 dN/dpTPHOS, calibration in
                                                                   • EMCAL and
                                                                     progress




Hot Matter-26/08/2010, ALICE physics, 2010, Karel Safarik, CERN
06/08/2010, ALICE @ ICHEP Paris P. Kuijer, NIKHEF                     Overview of LHC physics                34
                                                          Charm at 7 TeV
           D0→ K p                                                                     D0→ K p p p


                                                          Impact Parameter Resolution vs pT




        D+→ K p p                                                                      D*→ D0 p
                                                           80 mm @ 1 GeV




Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF                                              35
                                            Charm at very low pT



                                                                                     2 GeV


                                                                                   D0 cross section vs pT in |y| < 1
                                                                                   FONLL pQCD calculation




                                           - most of the cross section at low pT
                                           - shape at low pT very uncertain
                                           - 109 MB events => measure below 1 GeV
                                                (PID important at low pT !)


Hot Matter-26/08/2010, ALICE physics, 2010, Karel Safarik, CERN
06/08/2010, ALICE @ ICHEP Paris P. Kuijer, NIKHEF                       Overview of LHC physics                        36
                                                                  J/y @ 7 TeV
                   J/y → e+e- |y| < 1                                                        J/y → m+m-, y = 2.5–4.1




  - tough to measure J/y with our current low luminosity
   (also 1st year Pb–Pb luminosity will be very low -> priority on MB in pp)
  - ‘proof of performance’
      higher luminosity later this year and next year

Hot Matter-26/08/2010, ALICE physics, 2010, Karel Safarik, CERN
06/08/2010, ALICE @ ICHEP Paris P. Kuijer, NIKHEF                      Overview of LHC physics                         37
                                                           J/y → m+m-
            The acceptance and efficiency corrected distributions are
            compared to generated MC distribution




  “CDF pp 7TeV” parameterization
        pT extrapolated from CDF results
        y obtained from CEM calculations
        No polarization ( = 0)
         Javier Castillo                                  ICHEP2010 – Paris, France – 22/10/2010   38
Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF                                             38
                                                                  J/y → m+m-




                                                                                                 <pT2> vs √ s




                                                                                                 <pT> vs √ s


Hot Matter-26/08/2010, ALICE physics, 2010, Karel Safarik, CERN
06/08/2010, ALICE @ ICHEP Paris P. Kuijer, NIKHEF                      Overview of LHC physics                  39
                                             Event shape analysis
    Transverse sphericity S┴:
    eigenvalues of the momentum tensor Sxy


    small S┴:                                      large S┴:


                                                          S┴ vs Multiplicity 900 GeV   S┴ vs Multiplicity 7 TeV




Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF                                                           40
                             pQCD: High-pT particle correlations



                                                                       pTt
                                                                                                       Associated
                                ‘near’ side



                                                         ‘away’ side                                      Δf

                                         UE




               Trigger Particle                                                                             Trigger




                                                                  Trigger Particle: highest pT particle in event (pTt)
                                                                  Associate Particle: all the others (pTa)
Hot Matter-26/08/2010, ALICE physics, 2010, Karel Safarik, CERN
06/08/2010, ALICE @ ICHEP Paris P. Kuijer, NIKHEF                            Overview of LHC physics                  41
                                       „High‟-pT particle correlations
                                                                  pTt                             pTt




     - correlations present down to very low pT
     - study ‘mini-jet region (difficult with fully reconstructed jet ?)
Hot Matter-26/08/2010, ALICE physics, 2010, Karel Safarik, CERN
06/08/2010, ALICE @ ICHEP Paris P. Kuijer, NIKHEF                       Overview of LHC physics         42
                                                Charged „mini-jets‟




                   Width of ‘near’ side correlation => jT                       Width of ‘away’ side => <pT>pair
                   average transverse momentum                                  ~ mean jet acoplanarity ( ~ kT)
                   of fragments relative to jet axis


                   independent of √ s (well known)                              increases with √ s

Hot Matter-26/08/2010, ALICE physics, 2010, Karel Safarik, CERN
06/08/2010, ALICE @ ICHEP Paris P. Kuijer, NIKHEF                 Overview of LHC physics                          43
                                                                  UE vs. MC




Hot Matter-26/08/2010, ALICE physics, 2010, Karel Safarik, CERN
06/08/2010, ALICE @ ICHEP Paris P. Kuijer, NIKHEF                     Overview of LHC physics   44
                           Planned quick PbPb analysis
           multiplicity
           v2
           pT (RAA, RCP)
           HBT
           high pT correlations




                                                                               Wait until
                                                                              November for
                                                                                 PbPb


                                                          High multiplicity
                                                             pp event
Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF                                      45
                                                          Conclusions


         2010 running very successful
                  all detector, online, and offline systems ready
                  Alignment and calibration under control
                  about 500 million events collected

         Physics analysis well underway
            Heavy ions are our core business, starting in November
            Meanwhile study QCD with pp collisions
                Anti-baryon/baryon, HBT R vs kt, Lambda/K, ...




Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF                 46
Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF   47
                                 Backup

Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF   48
                            The LHC (and everything else) accelerates ..




                                                                .. and tense anticipation..

                                                           Monday, 23rd November, ~15:30
                  ..after concentrated preparations.. 49    in the ALICE Control Room
Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF
                          some anxious minutes waiting for collisions..

                                                               ~ 16:35




                                                          50
Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF
                                             Relief and jubilation..
                                                               Collisions in ALICE !!




                                                                 ~ 16:42
             .. and some celebration..
Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF                                 51
                        „First Physics‟ in the making




                                                                                                                           ~ 18:00




                                                    After years of looking at simulated data, there was no holding back:
                                                                       First physics results examined,
Hot Matter-26/08/2010, ALICE physics, P. Kuijer, NIKHEF
                                                             ca 1 hour after data taking finished (284 events !)..
                                                                                                                                     52

				
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