1. 6 th International Conference on Physics and Astrophysics of Quark Gluon Plasma December 6-10, 2010 Goa, India C. Zampolli for the ALICE Collaboration

2. Outline  Motivations  Open-charm at mid-rapidity  D mesons (a,b)  Heavy flavor electrons  Quarkonia at mid rapidity (c,d)  J/ψ  ee  PbPb perspectives  Summary and Conclusions 12/08/2010, ICPAQGPC. Zampolli - ALICE 2 (a) See R. Bala’s talk, parallel, today (b) See S. Dash’s poster, Tue (c) See D. Das’s talk, plenary, Thu (d) See S. Pal’s talk, parallel, today

3. 12/08/2010, ICPAQGPC. Zampolli - ALICE 3 Motivations

4.  Heavy flavors are mainly produced during the initial hard collisions  They are an important tool to probe the early phases of the evolution of the system  Open Heavy Flavors production:  Can be used in order to infer the properties of the medium  energy loss effect  Can be used as a baseline for quarkonia 12/08/2010, ICPAQGPC. Zampolli - ALICE 4

5. Motivations – II  Quarkonia production:  Can be used to understand the properties of the medium created during the collision  Suppression? Recombination? Enhancement?  Dissociation pattern of the various quarkonium related to initial temperature of the medium 12/08/2010, ICPAQGPC. Zampolli - ALICE 5 (S = measured / expected yields) PLB637 75 (2006) ~ 30 [GeV/fm 3 ] Recombination? J/Ψ melting?...or compensation? SPS RHIC LHC

6. Heavy Quarks in pp collisions  Test to pQCD in a new energy regime (~3.5÷7 × √s TEVATRON ) 12/08/2010, ICPAQGPC. Zampolli - ALICE 6  Fundamental baseline for PbPb  Number of cc (bb) pairs expected in 5% central PbPb:  2.76 TeV: 56 (2) (MNR with CTEQ6M + shadowing - mean of EKS98/EPS08) - MNR code: Mangano, Nason, Ridolfi, NPB373 (1992) 295 - EKS98, EPS08: Eskola et al., EPJC9 (1999) 61, JHEP07 (2008) 102  (*) c production at Tevatron on the upper edge of FONLL predictions (*)(*)

7. ALICE Heavy Flavor Program 12/08/2010, ICPAQGPC. Zampolli - ALICE 7  Open charm (a)  D 0  K π, K π π π (a)  D +  K π π  D*  D 0 π  D s  K K π (a,b)  Λ c  p K π (a)  Open charm and open beauty  D, B  e + X  D, B  μ + X  B  J/Ψ  ee  Quarkonia  J/Ψ  ee (μμ (c,d) ) (a) See R. Bala’s talk, parallel session, today (b) See S. Dash’s poster, Tue ITS TPC TRD TOF EMCAL (c) See D. Das’s talk, plenary, Thu (d) See S. Pal’s talk, parallel session, today MUON ITS: vertexing + tracking TPC: tracking + PID (π, K) TOF: PID (π, K, e) MUON: μ reco + id

8. pp collisions, 7 TeV 12/08/2010, ICPAQGPC. Zampolli - ALICE 8 D Mesons

9. D 0  K - π + signal 12/08/2010, ICPAQGPC. Zampolli - ALICE 9  10 8 events  1-12 GeV/c in 7 p T bins  Based on the displaced vertex topology of the decay  Vertexing and tracking  Reducing the background with PID information  K id  Signal at very low p T under study

10. D +  K - π + π + 12/08/2010, ICPAQGPC. Zampolli - ALICE 10  10 8 events  2-12 GeV/c in 6 p T bins  Based on the displaced vertex topology of the decay  Vertexing and tracking  Reducing the background with PID information  K id

11. D* +  D 0 π + 12/08/2010, ICPAQGPC. Zampolli - ALICE 11  10 8 events  2-12 GeV/c in 6 p T bins  Based on the displaced vertex topology of the decay  Vertexing and tracking  Reducing the background with PID information  K id  ITS standalone tracking fundamental for the low p t

12. dσ/dp t Spectra @ |y| < 0.5 12/08/2010, ICPAQGPC. Zampolli - ALICE 12  Raw yields corrected for efficiency and acceptance  B feed-down corrections using FONLL calculations  Evaluation from D meson impact parameter distributions (à la CDF) ongoing COMPATIBLE WITH pQCD (FONLL AND GM-VFNS) PREDICTIONS Normalization using σ MB from VdM scan D0D0 D+D+

13. D *+ dN/dp t and D Mesons Ratios 12/08/2010, ICPAQGPC. Zampolli - ALICE 13 RATIOS IN GOOD AGREEMENT WITH PREVIOUS EXPERIMENTS ee, H1, ZEUS: JHEP07 (2007) 074 CDF: PRL 91 (2003) 241804 Systematics evaluation well ongoing

14. pp collisions, 7 TeV 12/08/2010, ICPAQGPC. Zampolli - ALICE 14 Single Electrons

15.  Goal is to measure the cc and bb production cross sections through semileptonic decays of open charm and open beauty and to study energy loss of heavy quark mesons in the medium created in the collision  Heavy Flavor (HF) Single Electron spectrum extracted from a) “Cocktail” of background electrons sources (à la RHIC)  Photonic, dielectron decays of mesons, direct radiation, J/Ψ, Y b) Cut on impact parameter to select electrons, especially efficient for those from B  Analysis relying on:  High-quality tracks  Electron PID through TPC dE/dx and TOF information  TRD and EMCAL to be added soon 12/08/2010, ICPAQGPC. Zampolli - ALICE 15

16. Electron Cocktail  All ingredients – all sources of electrons:  Dalitz decays of neutral mesons (π 0, η, ω, η’, φ  γe + e - )  Photon conversions in the material  Direct radiation (direct photon conversions, virtual photons)  Weak kaon decays  Dielectron decays of vector mesons (ρ, ω, φ  e + e - )  Heavy flavor decays (open charm, open beauty, J/Ψ, Y) 12/08/2010, ICPAQGPC. Zampolli - ALICE 16  So far including:  Neutral pions (from data!)  Heavier mesons (π 0, η, ω, η’, φ, ρ)  Photon Conversion

17. Electron Spectrum and Cocktail  110 M minimum bias events  0.4 < p t < 4 GeV/c 12/08/2010, ICPAQGPC. Zampolli - ALICE 17 Data & cocktail Ratio Data/Cocktail  Systematics uncertainty from π 0 spectrum from data varying from +20% to -40% Excess of electrons wrt the cocktail from charm and beauty (+ J/ψ and direct radiation)

18. pp collisions, 7 TeV J/ψ  e + e - 12/08/2010, ICPAQGPC. Zampolli - ALICE 18 Quarkonia

19. J/ψ  e + e - @ |y| < 0.9  Goal is to measure the J/ψ production cross sections in the dielectron channel  Analysis relying on:  High quality tracks  Electron PID through TPC dE/dx  TOF and TRD to be added  Inclusive J/ψ (no B separation)  Signal extraction via bin counting in 2.90 < M inv < 3.15 GeV/c 2 (like-sign background removal) 12/08/2010, ICPAQGPC. Zampolli - ALICE 19 N J/ψ = 123 ± 16 3 × 10 8 Minimum Bias events

20. J/ψ Cross Section  p t integrated cross section  10 8 well calibrated events 12/08/2010, ICPAQGPC. Zampolli - ALICE 20  dN/dp t  3×10 8 partially calibrated events 14.5% from eff. corr. (selection + tracking + PID) 10% normalization +10%, -25% from polarization (*) CDF: Phys. Rev. D 71 (2005) 032001 PHENIX: Phys. Rev. Lett. 98 (2007) 232002 *

21. J/ψ Cross Section vs y  Measurement of dσ/dy in -4<y<0.9  Using the dimuon channel at forward rapidity 12/08/2010, ICPAQGPC. Zampolli - ALICE 21  ALICE measures inclusive J/ψ down to p T =0 in |y|<0.9 and 2.5<y<4  Also ATLAS and CMS, LHCb go down to p T =0, with 1.5<y<2.25, 1.6<y<2.4 and 2.5<y<4, respectively See also:  D. Das’s talk, plenary, Thu  S. Pal’s talk, parallel session, today

22. 12/08/2010, ICPAQGPC. Zampolli - ALICE 22 PbPb - Perspectives

23. Expected p t reach – from pp to PbPb 12/08/2010, ICPAQGPC. Zampolli - ALICE 23 pp 14TeV PbPb 5.5 TeV MC study ~1 year data taking  pp: 0.5 ÷ 20 GeV/c  PbPb: 1 ÷ 20 GeV/c

24. Some Prospects for PbPb 12/08/2010, ICPAQGPC. Zampolli - ALICE 24  R AA (a) : R h AA ≤R D AA ≤R B AA (a)(a) m b = 4.8 GeV Nucl.Phys.A783:417-425,2007 (b)(b) (b)(b)  D and B mesons can be used as v 2 probes  To study the thermalization of c and b quarks at low and intermediate p t (≤ 10 GeV/c)  to study the in-medium path dependence energy loss at higher momenta (≥ 10 GeV)  Quarkonia studies:  Suppression vs regeneration in the J/ψ production mechanism  Bottomonium resonances ( ϒ, ϒ ’ )  … MC study

25. So far… PbPb @ 2.76 TeV 12/08/2010, ICPAQGPC. Zampolli - ALICE 25 J/Ψ D+D+ D0D0

26. Summary and Conclusions  The rich and diverse ALICE Heavy Flavor program is well under-way  The ALICE performance in terms of vertex reconstruction, tracking and PID are the key tools  The first results from pp collisions @ 7 TeV have been shown  D mesons (see also R. Bala, S. Dash)  Single electrons  J/ψ dielectron channel  Forward rapidity μ analysis results presented at this Conference (D. Das, S. Pal)  pp results are the starting point for the PbPb data analyses  PbPb perspective have been shown 12/08/2010, ICPAQGPC. Zampolli - ALICE 26 “so many out-of-the-way things had happened lately, that Alice had begun to think that very few things indeed were really impossible.” L. Carrol, Alice’s Adventures In Wonderland

27. 12/08/2010, ICPAQGPC. Zampolli - ALICE 27

28. 12/08/2010, ICPAQGPC. Zampolli - ALICE 28 Back-Ups

29. Single Electron Raw Spectrum  Contamination for hadrons evaluated from data  Efficiency and acceptance corrections included  Correction for p t -dependent resolution (Bremsstrahlung) 12/08/2010, ICPAQGPC. Zampolli - ALICE 29 Inclusive spectrum, decays and conversions included Overall Efficiency from MC Corrected spectrum