John Harris (Yale U.) Winter Workshop, Big Sky MT, 1 – 8 Feb Physics in ALICE at the LHC

ALICE at the LHC John Harris (Yale U.) Winter Workshop, Big Sky MT, 1 – 8 Feb LHC Alice Dedicated “general purpose” Heavy Ion experiment at LHC

The ALICE Experiment John Harris (Yale U.) Winter Workshop, Big Sky MT, 1 – 8 Feb. 2009

ALICE Detectors & Acceptance (charged particles) µ arm central barrel -0.9 <  < 0.9  = 2  tracking, PID (TPC/ITS/ToF) single arm RICH (HMPID) single arm e.m. cal (PHOS) jet calorimeter (EMCal) forward muon arm 2.4 <  < 4 absorber, 3 T-m dipole magnet 10 tracking + 4 trigger chambers multiplicity detectors -5.4 <  < 3 including photon counting in PMD trigger & timing detectors 6 Zero Degree Calorimeters T0: ring of quartz window PMT's V0: ring of scint. Paddles John Harris (Yale U.) Winter Workshop, Big Sky MT, 1 – 8 Feb. 2009

The ALICE Experiment (Installation) John Harris (Yale U.) Winter Workshop, Big Sky MT, 1 – 8 Feb. 2009

ALICE Detectors in 2009 at LHC Complete – fully installed & commissioned –ITS, TPC, TOF, HMPID, MUONS, PMD, V0, T0, FMD, ZDC, ACORDE, TRIGGER, DAQ Partially completed –TRD (20%) completed now –PHOS (20%) completed now –EMCAL (20%) just completed, installation in current shutdown At start-up full hadron and muon capabilities Partial electron and photon capabilities John Harris (Yale U.) Winter Workshop, Big Sky MT, 1 – 8 Feb. 2009

6/27/2015 The TPC Performance John Harris (Yale U.) Winter Workshop, Big Sky MT, 1 – 8 Feb ~6.5% resolution in central Pb+Pb Energy loss (dE/dx) separation power to 50 GeV PID Tracking (cosmic rays)

First LHC Beam in ALICE John Harris (Yale U.) Winter Workshop, Big Sky MT, 1 – 8 Feb ALICE ready for LHC collisions. First LHC proton beams circulated on September 10 th, GeV/c proton + pixel interaction

Early p + p Physics in ALICE John Harris (Yale U.) Winter Workshop, Big Sky MT, 1 – 8 Feb “Day 1” physics with p + p: global event properties (energies - 0.9/10/14 TeV?) requires only several x 10K events vs N ch Multiplicity distributions

ALICE Heavy Ion Physics Overview: Soft Probes – “same as RHIC and Beyond” Expansion dynamics different from RHIC Soft physics measurements similar to RHIC + extended PID Day 1 physics + Hard Probes – Heavy Quarks Displaced vertices (D o  K -  +) from TPC/ITS Electrons in Transition Radiation Detector (TRD) Hard Probes – Quarkonia J/ , ,  ’ (excellent),  ’’(2-3 yrs),  ’ ??? Hard Probes – Jet Quenching Jets,  pi-zeros, leading particles to large p T John Harris (Yale U.) Winter Workshop, Big Sky MT, 1 – 8 Feb. 2009

Soft Physics in ALICE LHC Heavy Ions – expectations based on QCD predictions, p + p extrapolations, & RHIC results a lesson from RHIC  “expect the unexpected”  versatility!!  ALICE!! Soft Physics (p T ≤ 2 GeV/c) with heavy ions at LHC – Is there a smooth extrapolation from SPS  RHIC  LHC? ALICE Particle Multiplicities John Harris (Yale U.) Winter Workshop, Big Sky MT, 1 – 8 Feb dN ch /dy = 2600 dN ch /dy = 1200 ln(√s) extrapolation saturation model Eskola hep-ph/ J. Phys. G 30 (2004) 1540

Soft Physics in ALICE LHC Heavy Ions – expectations based on QCD predictions, p + p extrapolations, & RHIC results a lesson from RHIC  “expect the unexpected”  versatility!!  ALICE!! Soft Physics (p T ≤ 2 GeV/c) with heavy ions at LHC – smooth extrapolation from SPS  RHIC  LHC? expansion will be different (HBT, v2, T chem & T kin, strange/charm particles & resonances) John Harris (Yale U.) Winter Workshop, Big Sky MT, 1 – 8 Feb Hirano et al, nucl-th/ v2 N.Borghini & U.A.Weidemann, J.Phy.G 35 (2008)

Equilibrium / Non-Equilibrium in ALICE Non-equilibrium s (  s = 3 - 5) oversaturated Equilibrium  s = 1 Many additional questions: Strangeness enhancement? Correlation volume? Evolution in pp & PbPb? B. Hippolyte et al. EPJ C49 (2007)  at LHC expect : T ch = 161 ± 4 MeV  B = MeV John Harris (Yale U.) Winter Workshop, Big Sky MT, 1 – 8 Feb Andronic et al. nucl-th/ Rafelskiet al. E. J. Phys. C45 (2006) 61

Resonances ( , , K*, …)  Hadrons Reconst invariant mass spectrum, background subtract (like-sign method). Mass resolutions ~ MeV. p T statistical limits: 8 (  ) to 15 GeV/c ( ,K*) K*(892) 0 K  central Pb-Pb  K + K - Mass resolution ~ 1.2 MeV            central Pb-Pb Mass resolution ~ 2-3 MeV Invariant mass (GeV/c 2 ) Short-lived resonances: Invariant mass (GeV/c 2 ) Time difference between chemical and kinetic freeze-out In medium modifications of mass, width, comparison of hadronic and leptonic channels → partial chiral symmetry restoration? John Harris (Yale U.) Winter Workshop, Big Sky MT, 1 – 8 Feb. 2009

Resonances ( , , , J/  )  e + e - Short-lived resonances: John Harris (Yale U.) Winter Workshop, Big Sky MT, 1 – 8 Feb x 10 7 Pb+Pb events In medium modifications of mass, width, comparison of hadronic and leptonic channels → partial chiral symmetry restoration?

2 x 10 7 Pb+Pb events Short-lived resonances: In medium modifications of mass, width, comparison of hadronic and leptonic channels → partial chiral symmetry restoration? 2 x 10 7 Pb+Pb events -  : significance = J/  : significance = John Harris (Yale U.) Winter Workshop, Big Sky MT, 1 – 8 Feb Resonances ( , , , J/  )  e + e -

Hard Probe Rates in ALICE ALICE hard physics capabilities: - Electron/hadron disc. (TRD, EMCal) -  measurements (forward muon arm) - Good   discrimination (EMCal, PHOS) - Fast trigger on jets (EMCal) Hard Probes statistics in ALICE: 10 4 /year in minbias Pb+Pb: inclusive jets: E T ~ 200 GeV dijets: E T ~ 170 GeV   : p T ~ 75 GeV inclusive  : p T ~ 45 GeV inclusive e: p T ~ 30 GeV Thanks – Peter Jacobs John Harris (Yale U.) Winter Workshop, Big Sky MT, 1 – 8 Feb. 2009

Hard Probes in ALICE – Heavy Quarks Heavy Quarks (mass/color dep. of parton E-loss) Displaced vertices (D o  K -  +) from TPC/ITS Electrons in Transition Radiation Detector (TRD) John Harris (Yale U.) Winter Workshop, Big Sky MT, 1 – 8 Feb. 2009

Heavy Quark R AA at RHIC & LHC! Uncertainties at RHIC (bands > ±0.1 ) - perturbative production of c and b jets - ratio of c to b jets is very uncertain. Wicks & Gyulassy, Last Call for LHC Predictions RHIC LHC Heavy quark electrons at RHIC D & B mesons at LHC LHC: - Different slopes of spectra John Harris (Yale U.) Winter Workshop, Big Sky MT, 1 – 8 Feb. 2009

Charm & Beauty E-Loss Ratios in ALICE Displaced vertices (D o  K -  +) from tracking Electrons from Transition Radiation Detectors 1 nominal year: 10 7 central Pb-Pb events, 10 9 pp events errors: statistical (bars) and systematic (bands) Sensitive to color charge Sensitive to mass dep. E-loss calc.: Armesto, Dainese, Salgado, Wiedemann John Harris (Yale U.) Winter Workshop, Big Sky MT, 1 – 8 Feb. 2009

Charm and Beauty E-Loss : R AA D 0  K  1 year at nominal luminosity (10 7 central Pb-Pb events, 10 9 pp events)) B  e + X D +  K  m C = 1.2 GeV m C = 0 m b = 4.8 GeV B  e E-loss calc: Armesto, Dainese, Salgado, Wiedemann John Harris (Yale U.) Winter Workshop, Big Sky MT, 1 – 8 Feb. 2009

Hard Probes in ALICE – Quarkonia Heavy Quarks (mass/color dep. of parton E-loss) Displaced vertices (D o  K -  +) from TPC/ITS Electrons in Transition Radiation Detector (TRD) Quarkonia (Initial T, Debye screening, recombination,..) J/ , ,  ’ (excellent),  ’’(2-3 yrs),  ’ (very difficult) John Harris (Yale U.) Winter Workshop, Big Sky MT, 1 – 8 Feb. 2009

John Harris (Yale) Tamura Symposium, U. T. – Austin, 20 – 22 Nov Quarkonia John Harris (Yale U.) US LHC User’s Meeting, 24 October 2008 T/T C 1/  r  [fm -1 ]  (1S) J/  (1S)  c (1P)  ’(2S)  b ’(2P)  ’’(3S) Karsch hep-lat/ v2 Measure melting order of cc:  ’,  c, J/  bb:  ’’,  ’,  Heavy Quarks (mass/color dep. of parton E-loss) Displaced vertices (D o  K -  +) from TPC/ITS Electrons in Transition Radiation Detector (TRD) Quarkonia (Initial T, Debye screening, recombination,..) J/ , ,  ’ (excellent),  ’’(2-3 yrs),  ’ (very difficult)

6/27/2015 Particle Charmonia  +  - Charmonia e + e - Bottomonia  +  - Bottomonia e + e - mass plots (- bkg) accept. -4 <  < -2.5|  | < <  < -2.5|  | < 0.9 MM 65 MeV35 MeV90 MeV S /  (S+B) J/  150,  ’ 7J/  245  30,  ’ 12,  ’’ 8  21,  ’ 8 channel ,  ’ ,  ’,  ’’ ,  ’, no  ’’ ptpt J/  0-20 GeV J/  0-10 GeV  0-8 GeV-- Quarkonia Performance dN ch /dy = 4000 in central Pb-Pb for 1 month

Hard Probes in ALICE – Jet Quenching Heavy Quarks (mass/color dep. of parton E-loss) Displaced vertices (D o  K -  +) from TPC/ITS Electrons in Transition Radiation Detector (TRD) Quarkonia (Initial T, Debye screening, recombination,..) J/ , ,  ’ (excellent),  ’’(2-3 yrs),  ’ (very difficult) Jet Quenching (in next talk by Rene Bellwied) (E-loss, parton density, fragmentation, medium response) Jets,  pi-zeros, leading particles to large p T Modification of fragmentation Medium response to E deposition - dissipation on near- and away-side John Harris (Yale U.) Winter Workshop, Big Sky MT, 1 – 8 Feb. 2009

Summary & Questions to Address ALICE – is a versatile, general purpose heavy ion detector at LHC will contribute significantly to understanding of (soft & hard) HI physics ALICE to address general (Soft Physics) Questions: How does the system evolve and thermalize from its initial state? What are the properties of the quark-gluon plasma at LHC energies? Is QCD Phase Diagram featureless above Tc? Coupling strength vs T….? Are there new phenomena? ALICE to address Physics Questions with Hard Probes: What is the behavior of c-cbar and b-bar states in-medium? (T i, screening/suppression, enhancement?) Can we understand parton energy loss at a fundamental level? Medium modifications? e.g. jet energies in ALICE up to ~ 225 GeV possible (stats) B-jets up to 80 – 90 GeV (stats in one PbPb month) Flavor dependence? (D, B, quark- and gluon-jets?) Can we understand the hadronization (fragmentation) process? Theory? Range of validity of theories (hydro, non-pQCD, pQCD, strings…)? Can there be new developments in theory, and understanding across fields? (lattice, hydro, string, pQCD E-loss,…)

End John Harris (Yale U.) Winter Workshop, Big Sky MT, 1 – 8 Feb. 2009