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First Alice Physics Week, Erice, Dec 4 9, Heavy Flavor (c,b) Collectivity at RHIC and LHC Kai Schweda, University of Heidelberg A. Dainese, X. Dong, J. Faivre, Y. Lu, H.G. Ritter, L. Ruan, A. Shabetai, P. Sorensen, N. Xu, H. Zhang, Y. Zhang.

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First Alice Physics Week, Erice, Dec 4 9, Outline 1)Introduction 2)Multi-strange baryons and elliptic flow 3)Heavy-quark (b,c) Collectivity 4)Summary

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First Alice Physics Week, Erice, Dec 4 9, Quark Gluon Plasma Source: Michael Turner, National Geographic (1996) Quark Gluon Plasma: (a)Deconfined and (b)thermalized state of quarks and gluons Study partonic EOS in high energy nuclear collisions (?) Probe thermalization using heavy-quarks

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First Alice Physics Week, Erice, Dec 4 9, Pressure, Flow, … Thermodynamic identity – entropy p – pressure U – energy V – volume = k B T, thermal energy per dof In A+A collisions, interactions among constituents and density distribution lead to: pressure gradient collective flow number of degrees of freedom (dof) Equation of State (EOS) cumulative – partonic + hadronic

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First Alice Physics Week, Erice, Dec 4 9, Kinetic Freeze-out at RHIC Disentangle collective flow ( T ) and random walk (T). 1) ,K and p change smoothly from peripheral to central collisions. 2) At the most central collisions, reaches 0.6c. 3) Multi-strange particles , are found at higher T and lower Sensitive to early partonic stage! What about v 2 ? 4) Single sudden freeze-out*: all collectivity from partonic stage! STAR: NPA715, 458c(03); PRL 92, (04); 92, (04). *A. Baran, W. Broniowski and W. Florkowski; nucl-th/

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First Alice Physics Week, Erice, Dec 4 9, Anisotropy Parameter v 2 y x pypy pxpx coordinate-space-anisotropy momentum-space-anisotropy Initial/final conditions, EoS, degrees of freedom

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First Alice Physics Week, Erice, Dec 4 9, Collectivity, Deconfinement at RHIC - v 2, spectra of light hadrons and multi-strange hadrons - scaling with the number of constituent quarks At RHIC, I believe we have: Partonic Collectivity êDeconfinement Thermalization ? PHENIX: PRL91, (03) STAR: PRL92, (04), PRL95, (05). S. Voloshin, NPA715, 379(03) Models: Greco et al, PRC68, (03) X. Dong, et al., Phys. Lett. B597, 328(04).

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First Alice Physics Week, Erice, Dec 4 9, Heavy-Flavor Quarks Plot: B. Mueller, nucl-th/ Symmetry is broken: QCD dynamical mass EW Higgs mass Even in a QGP, charm and beauty quark-mass heavy ! If heavy quarks flow: frequent interactions among all quarks light quarks (u,d,s) likely to be thermalized Plot: B. Mueller, nucl-th/ Mass (MeV/c 2 )

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First Alice Physics Week, Erice, Dec 4 9, Charm-quark Elliptic Flow V. Greco et al., PLB 595(2004)202. Coalescence approach Heavy-quark collective flow observable in D-meson v 2 Large partonic cross sections needed Frequent interactions Challenge to theory ? AMPT transport model B. Zhang et al.,PRC 72(2005) D = (cu)

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First Alice Physics Week, Erice, Dec 4 9, The key point is to determine Heavy-Flavor Collectivity

11 First Alice Physics Week, Erice, Dec 4 9, V. Greco et al. PLB 595(2004)202 B. Zhang et al. nucl-th/ Non-photonic electron v 2 c (b) e + X Large syst. uncertainties due to large background Experimental data do not agree at 2

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First Alice Physics Week, Erice, Dec 4 9, Heavy-flavor Energy Loss Heavy-flavor decay electrons: Probe interaction with medium Induced gluon radiation only Plus elastic collisions Better agreement with data Start understanding heavy flavor interaction with the medium ! Disentangle b,c by direct reconstruction of B at LHC ! Calculations: M. Djordjevic et al.

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First Alice Physics Week, Erice, Dec 4 9, Heavy-Flavor in ALICE TPC: main tracking device ITS: high spatial resolution, D,B decay vertex TRD: good electron PID (high pion rejection), J/ , , B,D e ToF: extend PID to large p T

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First Alice Physics Week, Erice, Dec 4 9, Heavy-Flavor in ALICE : D 0 K - + |y| 1 GeV/c Pb + Pb central, 1 st year D 0 K + Expected stat. + syst. uncertainties small Probe heavy-flavor flow ! D 0 simulations: A. Dainese, nucl-ex/ Other (possible?) channels: c pK (BR ~ 5%) c K 0, K +

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First Alice Physics Week, Erice, Dec 4 9, J/ Enhancement at LHC Statistical hadronization strong centrality dependence of J\ yield at LHC Need total charm yields ! Measure D 0, D ±, c, c Probe deconfinement and thermalization Calculations:P. Braun Munzinger, K. Redlich, and J. Stachel, nucl-th/

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First Alice Physics Week, Erice, Dec 4 9, Multiply Heavy-flavored Hadrons F. Becattini, Phys. Rev. Lett. 95, (2005); P. Braun Munzinger, K. Redlich, and J. Stachel, nucl-th/ Statistical hadronization - de-confined heavy-quarks - equilibrated heavy-quarks Enhancement up to x1000 ! Measure cc, cc, B c, ( ccc ) Need total charm yields Probe deconfinement and thermalization QGP ! Quarks and gluons hadrons Pb+Pb ccc / D : p+p x1000

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First Alice Physics Week, Erice, Dec 4 9, Summary Multi-strange hadrons and flow Partonic collectivity at RHIC Deconfinement at RHIC Measure spectra, elliptic flow and yields of D 0, D , D + s, C, J/ , B ± Probe (u,d,s)-quark thermalization ALICE: TPC + Vertex + TRD +ToF

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