OPEN HEAVY FLAVORS 1 Heavy Flavor Heavy quarks

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OPEN HEAVY FLAVORS 1

OPEN HEAVY FLAVORS 1

Heavy Flavor Heavy quarks produced in the early stages of the collisions (high Q

Heavy Flavor Heavy quarks produced in the early stages of the collisions (high Q 2) effective probe of the high-density medium created in heavy-ion collisions In-medium energy loss expected to be smaller for heavy quarks than for light quarks and gluons due to color charge and dead cone effect [1] Heavy Flavor detection in pp: - Reference for Heavy Ions -Intrinsic interest: constrain with experimental data p. QCD calculations HF carefully studied also in pp collisions in ALICE [1] 2

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D meson RAA • D 0, D+ and D*+ RAA compatible within uncertainties in

D meson RAA • D 0, D+ and D*+ RAA compatible within uncertainties in the measured range [1, 36] Ge. V/c. • Suppression up to a factor 5 for D 0, D+ and D*+ at p. T~ 10 Ge. V/c. Average D-meson RAA: – p. T < 8 Ge. V/c hint of slightly less suppression than for light hadrons – p. T > 8 Ge. V/c both (all) very similar no indication of color charge depend. 9

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D meson: RAA and elliptic flow Together with RAA , also v 2 is

D meson: RAA and elliptic flow Together with RAA , also v 2 is sensitive to medium transport properties Low- p. T v 2: pressure gradient in medium expansion degree of thermalization High p. T v 2: path - length dependence of energy loss • Non-zero D meson v 2 observed; Comparable to that of light hadrons • Simultaneous description of RAA and v 2 c-quark transport coefficient in medium 11

… adding Ds to charm RAA The relative yield of D+s with respect to

… adding Ds to charm RAA The relative yield of D+s with respect to non-strange D meson expected to be enhanced in Pb-Pb collisions in the intermediate momentumrange if charm quarks hadronize via recombination in the medium [1 ] Strong suppression (~ 4– 5 ) at p. T above 8 Ge. V/c ; uncertainty will improve with future pp and Pb–Pb data taking 12 [1] I. Kuznetsova, J. Rafelski, Eur. Phys. J. C 51: 113 -133, 2007; M. He, R. J. Fries and R. Rapp, ar. Xiv: 1204. 4442 [nucl-th].

v 2 RAA Heavy-flavor electrons 13

v 2 RAA Heavy-flavor electrons 13

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Heavy-flavor muons Similar behaviour of HF muons and electrons 15

Heavy-flavor muons Similar behaviour of HF muons and electrons 15

QUARKONIUM 16

QUARKONIUM 16

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J/ 18

J/ 18

J/ q LHC energies : Enhancement via (re)generation of quarkonia, due to the large

J/ q LHC energies : Enhancement via (re)generation of quarkonia, due to the large heavy-quark multiplicity ? (A. Andronic et al. ; PLB 571(2003) 36) Braun-Munzinger & Stachel, Nature Vol. 448 (2007) 19

J/ : RAA vs Npart Forward rapidity: J/ m+m- Mid rapidity: J/ e+e- q

J/ : RAA vs Npart Forward rapidity: J/ m+m- Mid rapidity: J/ e+e- q Comparison with RHIC (PHENIX) q Stronger centrality dependence at lower energy; systematically larger RAA values for central events in ALICE q Behaviour qualitatively expected in a (re)generation scenario Look at theoretical models 20

J/ : RAA vs Npart Forward rapidity: J/ m+m- Mid rapidity: J/ e+e- q

J/ : RAA vs Npart Forward rapidity: J/ m+m- Mid rapidity: J/ e+e- q Comparison with models q X. Zhao and R. Rapp, Nucl. Phys. A 859(2011) 114 q Y. Liu, Z. Qiu, N. Xu and P. Zhuang, Phys. Lett. B 678(2009) 72 q A. Capella et al. , Eur. Phys. J. C 58(2008) 437 and E. Ferreiro, priv. com. q Models including a large fraction (>50% in central collisions) of J/ produced from (re)combination or models with all J/ produced at hadronization can describe ALICE results for central collisions in both rapidity ranges 21

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J/ : RAA vs Npart in p. T bins vs. theory q J/ production

J/ : RAA vs Npart in p. T bins vs. theory q J/ production via (re)combination should be more important at low transverse momentum Compare RAA vs Npart for J/ in different p. T intervals: low-p. T (0<p. T<2 Ge. V/c) high-p. T (5<p. T<8 Ge. V/c) q Different suppression pattern for low and high-p. T J/ smaller RAA for high p. T J/ q In the models, ~50% of low-p. T J/ are produced via (re)combination, while at high p. T the contribution is negligible fair agreement from Npart~100 onwards 23

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J/ : non-zero elliptic flow at the LHC q Flow studies Complements indications obtained

J/ : non-zero elliptic flow at the LHC q Flow studies Complements indications obtained from RAA studies q STAR: v 2 compatible with zero everywhere q ALICE: hint for non-zero v 2 in both q 20 -60% central events in 2<p. T<4 Ge. V/c q 5 -20% and 20 -40% central events for 1. 5<p. T<10 Ge. V/c q Significance up to 3. 5 for chosen kinematic/centrality selections q Qualitative agreement with transport models including regeneration 28

Highlights on J/ studies in pp collisions -I 29

Highlights on J/ studies in pp collisions -I 29

Highlights on J/ studies in pp collisions -II 30

Highlights on J/ studies in pp collisions -II 30

CONCLUSIONS AND PERSPECTIVES 31

CONCLUSIONS AND PERSPECTIVES 31

Conclusions and plans • ALICE is obtaining a large number of physics results from

Conclusions and plans • ALICE is obtaining a large number of physics results from the first two LHC heavy-ion runs: • bulk, soft probes; • high-p. T probes; • heavy-flavours and quarkonium ; • Entering the precision measurement era of QGP • before LS 2 (2018): p–Pb and Pb–Pb, higher energy. • Long-term upgrade for high-luminosity LHC based on: • ambitious physics programme • clear detector upgrade plan for improved vertexing and tracking • high-rate capability of all subdetectors 32

First p-Pb collisions in ALICE with the “pilot” run on September 12, 2012 Thanks

First p-Pb collisions in ALICE with the “pilot” run on September 12, 2012 Thanks for your attention 33