Presentation is loading. Please wait.

Presentation is loading. Please wait.

Ginés MARTINEZ, SUBATECHRencontres de Moriond March 17-24 20011 The heavy ion collider LHC A L I C E Ginés MARTINEZ # for the ALICE Collaboration.

Similar presentations


Presentation on theme: "Ginés MARTINEZ, SUBATECHRencontres de Moriond March 17-24 20011 The heavy ion collider LHC A L I C E Ginés MARTINEZ # for the ALICE Collaboration."— Presentation transcript:

1 Ginés MARTINEZ, SUBATECHRencontres de Moriond March The heavy ion collider LHC A L I C E Ginés MARTINEZ # for the ALICE Collaboration # Photon SUBATECH(IN2P3/CNRS – ENM - UN) Nantes, France

2 Ginés MARTINEZ, SUBATECHRencontres de Moriond March Outlook 1.Why a Heavy Ion LHC? 2.Goals 3.Building ALICE

3 Ginés MARTINEZ, SUBATECHRencontres de Moriond March The study of the Quark Gluon Plasma QCD-thermodynamics Properties of the QGP and of the phase transition: –Chiral transition –Deconfinement Lattice QCD calculations n f =2 T c = 173±8±SysErr MeV n f =3 T c = 153±8±SysErr MeV c = 700 ± 300 MeV Krasch QM2001

4 Ginés MARTINEZ, SUBATECHRencontres de Moriond March Towards QCD thermodynamics The TOOLS: Heavy Ion Collisions: SPS => RHIC => LHC The relation with QCD at finite temperature –The pp & pA baseline –Equilibration –Probes of QGP formation? –QGP Initial conditions? Collision dynamics

5 Ginés MARTINEZ, SUBATECHRencontres de Moriond March collision dynamics p+p and p+A baseline ! Sensitivity to late stages in HI collisions! The QGP phase Final state probes Penetrating probes

6 Ginés MARTINEZ, SUBATECHRencontres de Moriond March Why HI LHC ? Central collisions SPSRHICLHC s 1/2 (GeV) dN ch /dy x10 3 (GeV/fm 3 ) V f (fm 3 )10 3 7x10 3 2x10 4 QGP (fm/c) < (fm/c) ~1~0.5<0.2 J. Schukraft LHC : Hotter – bigger - longer

7 Ginés MARTINEZ, SUBATECHRencontres de Moriond March The gluon-gluon physics… Gluon distribution in nuclei grows for small values of x = 2p T /s 1/2 and high gluon densities are reached. For high densities ( T >> QCD ) in large nuclei & small x, the gluon distribution can be computed in the weak coupling method. The classical color field. A large number of gluons are freed in the early stage of the collision => Equilibration PRD10(74)1649, PRC49(94)2233, PRD49(94)3352, PRD53(96)458, PRC56(97)2219

8 Ginés MARTINEZ, SUBATECHRencontres de Moriond March Better connection with QCD theory (via the asymptotically free field theory) A E – Initial gluon multiplicity (R.Venugopalan QM01, PRL86(01)1717) – Initial equilibration conditions (D. Son QM01,hep-ph/ ) – Longer lifetime of the plasma – Ideal plasma c ~ 5 : higher T – Zero baryon density (already p/p ~ RHIC) – New probes : Jets, Open charm & beauty, bottonium Advantages of Pb+Pb LHC

9 Ginés MARTINEZ, SUBATECHRencontres de Moriond March Final state probes Forward energy dN/dy hadron pT distribution Particle ratios Strange particles Multiplicity Energy Density HBT and dynamical evolution Freeze-out temperature Fluctuations Collective motion s 1700 Ks 700 s 570 p, n, p, n s …. -1< <1 5.5A TeV

10 Ginés MARTINEZ, SUBATECHRencontres de Moriond March Penetrating probes Real and virtual photons Quarkonia: J/ & Y Open Charm & Beauty Light vector mesons Jets Initial stage Thermal radiation: T ini Colour screening of heavy quarks Jet-matter interaction Chiral transition

11 Ginés MARTINEZ, SUBATECHRencontres de Moriond March Jet Matter interaction BA 1-3 GeV/fm # # Interference with vacuum and LPM, Jet enhancement E jet dependence of E p T > 10 – 20 GeV 1.High p T particle distributions 2.Identification of jets … 3.Tagging with photons: High p T particles Jets Looking for Jet matter interaction: Urs. Wiedemann QM2001 et NPB588(00)203 Large production of LHC energies 1 jet/GeV/s in the ALICE acceptance at E T =50 GeV

12 Ginés MARTINEZ, SUBATECHRencontres de Moriond March Building ALICE Event Characterisation dN ch /dy pT distribution Particle ratios Strange baryons Fluctuations Light vector mesons Quarkonium Open charm & beauty Photon & Dilepton Jet quenching …

13 Ginés MARTINEZ, SUBATECHRencontres de Moriond March dN ch /d =1 ~ 8000 Time Projection Chamber: Main tracking detector of ALICE central barrel Inner radius: Track separation R in = 0.8 m Outer radius: dE/dx & p resolution # R out = 2.5 m Large acceptance < Hz rate capability MWPC read-out 32 m 2, 40% Oc pads x 500 time bins 60 Mbyte/evt => DC, RoI, L3 … # Magnetic field of the L3 magnet 0.4T 5 GeV/c 1.PID below ~600 MeV/c 2.Low p tracks Tracking efficiency ~90% 2 tracks eff. 80% p>15 MeV/c TPC 5 m Ne+CO 2 (10%)

14 Ginés MARTINEZ, SUBATECHRencontres de Moriond March The ALICE PID pT distributions Particles ratios: T freeze-out Fluctuations Strangeness production Light vector mesons Open charm Jet physics 0.5 < p < 5 GeV/c e,, K, p Time of Flight High Momentum Particle Identification Transition Radiation Detector ToF prototype ALICE solution Large acceptance MRPC = 150 ps,K,p 0.5

15 Ginés MARTINEZ, SUBATECHRencontres de Moriond March High momentum particles HMPID High Momentum PID: Hard processes 1 GeV/c < p < 5 GeV/c Rich-imaging technique Small acceptance 7x

16 Ginés MARTINEZ, SUBATECHRencontres de Moriond March Electron Identificator of ALICE Electron detector pion rejection Large acceptance Transition Radiation Detector 6x J/ in Zero baryon density Open charm normalization J/ source from Open Beauty D annihilation? production Light vector resonances: e channel ~ 10 3 E X ~ 3-30 KeV Pb+Pb central collisions TRD

17 Ginés MARTINEZ, SUBATECHRencontres de Moriond March Primary and secondary Vertex Position Secondary vertex from hyperon decays Open charm & beauty physics Tracking of low pT particles Improving momentum resolution Strangelets Large acceptance tracks ~100 m in r 6 Silicon layers: 1.2 Silicon Pixel layers 2.2 Silicon Drift layers 3.2 Silicon Strip layers ITS K- p ITSITS D =>K evt

18 Ginés MARTINEZ, SUBATECHRencontres de Moriond March Photon detection Thermal radiation High p t physics Tagged jets 1200 p T >40 GeV/c EM calorimeter PbWO4: spectrometer: 0 Small acceptance < p T < 5 GeV/c 5< p T <100 GeV/c 5x PHOS Module PHOS Thermal/Decay p T (GeV/c) 4 5% hep-ph/

19 Ginés MARTINEZ, SUBATECHRencontres de Moriond March Di muon channel DiMuon Quarkonium physics: J/ and Y families ~ 100 MeV 2.4 < < 4.0 e coin.: Intermediate rapidity DD, BB production

20 Ginés MARTINEZ, SUBATECHRencontres de Moriond March ALICE = The result of QGP physics requirements at LHC + PMD FMD CASTOR ZDC Trigger DAQ Offline

21 Ginés MARTINEZ, SUBATECHRencontres de Moriond March Running conditions 5.5A TeV 10 6 s per year 8000 Hz (L=10 27 cm -2 s -1 ) Data rate full ALICE 50 Hz (TPC challenge) pp & pA running Lighter higher luminosity. Beginning 2007

22 Ginés MARTINEZ, SUBATECHRencontres de Moriond March conclusions HI in LHC: a rigorous step towards the QGP physics –Perturbative + weak coupling methods –Direct partonic probes: Jets. The LHC HI dedicated experiment: ALICE –Penetrating and final state probes 884 members & 28 countries & 77 institutes CERN March-April 2007

23 Ginés MARTINEZ, SUBATECHRencontres de Moriond March A new research domain Quark Matter 2002 in Nantes


Download ppt "Ginés MARTINEZ, SUBATECHRencontres de Moriond March 17-24 20011 The heavy ion collider LHC A L I C E Ginés MARTINEZ # for the ALICE Collaboration."

Similar presentations


Ads by Google