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ALICE potential for H eavy F lavour P hysics. Gines MARTINEZ-GARCIA for the ALICE collaboration Subatech, Nantes, France. Physics Motivations. Probing and characterizing the quark gluon plasma (QGP) in Heavy-Ion collisions;
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ALICE potential for Heavy Flavour Physics Gines MARTINEZ-GARCIA for the ALICE collaboration Subatech, Nantes, France
Physics Motivations • Probing and characterizing the quark gluon plasma (QGP) in Heavy-Ion collisions; • Energy loss of Heavy Quarks (HQ) in hot and high density medium formed in AA central collisions: quark coupling and dead-cone effect; • Brownian motion and coalescence of low pT HQ in the QGP; • Dissociation (and regeneration) of quarkonia in hot QGP; • Heavy flavour physics in pp collisions: small x physics, pQCD, HQ fragmentation functions, gluon shadowing, Quarkonia production mechanism; Motivations
Heavy Quarks in HIC at LHC • Small xBj (10-3 –10-5); • DtQ ~ 0.04 –0.15 fm/c; • DtQ<< tQGP << tQ; • Shadowing / Saturation; • HQ energy loss in QGP; • HQ thermalization (low pT); L.O. HQ @LHC
J/Y regeneration J/Y melting PLB571 36 (2003) Charmonia in HIC at LHC RHIC SPS LHC PLB637 75 (2006) • Melting of Y’ and c at SPS and RHIC, and melting of J/Y at LHC? • Magic cancellation between J/Y suppression and J/Y regeneration? 22 (39)% of J/Y (Y’) from open beauty meson decays. HQ @LHC
PRD64,094015 cb(1P) cb(2P) (3S) (2S) (1S) SPS RHIC LHC Bottomonia in HIC at LHC CUSB Detector(Cornell) • First measurement of Bottomonia. • Regeneration is expected to be small at LHC. • (1S) melts only at LHC. • (2S)/(1S) as a function of centrality and pT. Dm(3S-2S) = 332 MeV/c2 45 (30)% of feed-down from higher resonances for (1S) ((2S)) HQ @LHC
ALICE Capabilities • ALICE combines electronic, muonic and hadronic channels; • ALICE covers down to pT ~ 0 for quarkonia and open charm; • ALICE covers central (|h|<0.9) and forward (-4.0<h<-2.5) regions; • High precision vertexing in the central barrel; ALICE
Physics Analysis • Hadronic decays: • D0K-p+, D+-K-+p+-p+-, DsK K*, Dsfp, … • Leptonic decays: • Single lepton analysis: • Open charm, open beauty, electro-weak bosons; • Invariant mass analysis of lepton pairs: • BB, DD, BDsame, J/Y, Y’, family, B J/Y + anything; • Multi-lepton analysis : • BB J/ym m m m ; ALICE
1<pT<2 GeV/c D0 K-+ channel • High precision vertexing, better than 100 mm (ITS); • High precision tracking (ITS+TPC); • K and/or p identification (TOF). F. ANTINORI, A. DAINESE et al. 109 pp 108 pPb 107 PbPb 107 central PbPb D Kp Open Flavours
D+- K-++ channel • Building Kpp triplets from Kp pairs (as in D0 analysis); • Secondary vertex quality: <180mm, pointing angle: >0.995 and dist to primary vertex: >1900 mm; QM06 Poster: E. BRUNA, F. PRINO et al. Scaled to 107central PbPb PbPb central Significance for dNch/dy=6000 ~ 40 for dNch/dy=2000 ~ 90 Open Flavours
Open Beauty from single e • Electron Identification (TRD+TPC); • High precision vertexing (ITS); • Subtraction of the open charm contribution. F. ANTINORI, M. LUNARDON, R. TURRISI et al. 107 central PbPb Open Flavours
high mass mm low mass mm Open Beauty from m and mm QM06 Poster: N. BASTID, Ph. CROCHET, R. GUERNANE et al. Single Muons BDsame BB 5% central PbPb Open Flavours
Energy Loss Physics Charm Production: Quark versus gluon Energy Loss Lower quark coupling Beauty production: Mass dependence of Energy Loss Dead cone effect ALICE PPR Vol.2. J. Phys. G: Nucl. Part. Phys. 32 1295 Open Flavours
Quarkonia in ALICE J/Y J/Y Di-electron channel |h|<0.9 -4.0<h<-2.5 Di-muon channel -4.0<h<2.5 Until pT = 0 |h|<0.9 Quarkonia
13x104 J/y pT=0-10 GeV/c 900 (1S) Quarkonia in the electron channel • Electron Identification (TRD+TPC); • Tracking : ITS+TPC+TRD; • 2x108 central PbPb events (no e-trigger). QM06 Poster: W. SOMMER, C. BLUME et al. 10% central PbPb dNch/dy = 3000 Quarkonia
Quarkonia in the muon channel PbPb cent, 0 fm<b<3 fm F. GUERIN, S. GRIGORYAN et al. Yields for baseline • (1S) & (2S) : 0-8 GeV/c • J/Y high statistics: 0-20 GeV/c • Y’ poor significance • (3S) ok, but 2-3 run needed. Quarkonia
J/y (polarization) in pp R.. ARNALDI, D. STOCCO, E. SCOMPARIN, E. VERCELLIN et al. a>0 Transverse a=0 a<0 Longitudinal Possible with >50000 J/y ; Error below 10%; Bgk contribution small; Systematics in the J/y acceptance due to polarization ignorance bellow 10%. p+p at 14 TeV Nominal run 3x106 J/y (mm) pT 0-20 GeV/c Quarkonia
Suppression Scenarii • Suppression-1 • Tc =270 MeV • TD/Tc=1.7 for J/Y • TD/Tc= 4.0 for . • Suppression-2 • Tc=190 MeV • TD/Tc=1.21 for J/Y • TD/Tc= 2.9 for . Ph. CROCHET, F, GUERIN, R. GUERNANE, S. GRIGORYAN et al. PRC72 034906(2005) Hep-ph/0507084(2005) Good sensitivity J/Y, (1S) & (2S) Quarkonia
b W Nm+/Nm- ~ 0.4 Electroweak Boson Detection Z. CONESA, L. APHECETCHE, Ch. FINCK and G. MARTINEZ PbPb MB 14400 muons from W • Well known from SM (better than 10%); • In principle no-interaction with QGP; • Non explored region: • (M, x) = (80-90 GeV/c2, 10-3 - 10-4); • Luminosity and detector efficiency cross-check; • Reference of quark (b) energy loss; Di-muons from Z0 240 Z0 mm in MB PbPb 2400 Z0mm in MB ArAr ElectroWeak
Conclusions • Heavy Flavour production will be measured by ALICE in A+A collisions at LHC energies; • Exclusive open charm (D0, D+) combined to single-lepton and di-lepton continuum measurements of beauty; • Huge statistics on charmonia: v2, polarization; • Regeneration: Centrality and pT dependance • Bottomonia measurement: (2S)/(1S); • Electro-weak boson can be measured in AA: reference for beauty energy loss; • Ds, Lc, J/y from B, multi-muon events, etc. have not been addressed in this talk but should be accessible with ALICE. Conclusions
Acknowledgements Special thanks to R. Arnaldi, F. Antinori, L. Aphecetche, N. Bastid, Ch. Blume, E. Bruna, Z. Conesa del Valle, Ph. Crochet, A. Dainese, Ch. Finck, S. Grigoryan, F. Guerin, M. Lunardon, F. Prino, K. Safarik, E. Scomparin, R. Turrisi, J. Schukraft, W. Sommer, D. Stocco and E. Vercellin for fruitful discussions and the preparation of this talk. Caminante, son tus huellas el camino, y nada mas; caminante no hay camino, se hace el camino al andar Antonio Machado (H. S. QM2002, Nantes) ALICE will begin to walk next year!