260 likes | 378 Views
Heavy Flavor and Deconfinement. Ralf Rapp Cyclotron Institute + Dept. of Physics & Astronomy Texas A&M University College Station, TX USA Sapore Gravis Workshop Nantes (France), 02.-05.06.13. 1.) Introduction: A “Calibrated” QCD Force. V [½ GeV]. [Kaczmarek
E N D
Heavy Flavor and Deconfinement Ralf Rapp Cyclotron Institute + Dept. of Physics & Astronomy Texas A&M University College Station, TX USA Sapore Gravis Workshop Nantes (France), 02.-05.06.13
1.) Introduction: A “Calibrated” QCD Force V [½GeV] [Kaczmarek et al ‘03] r [½ fm] • Vacuum charm-/bottomonium spectroscopy well described • Confinement?! Operational criterion: linear part of potential • most sensitive to J/y + ’ (EBCoul(J/y) ~ 0.05 GeVvs. 0.6 GeVexp.) • nonperturbative treatment • potential approach in medium?
Outline 1.) Introduction 2.) Heavy Quark/onium in QGP 3.) Quarkonium Transport 4.) Comparison to RHIC + LHC Data 5.) Conclusions
2.) Thermodynamic T-Matrix in QGP • Lippmann-Schwinger equation In-Medium Q-QT-Matrix: - • potential Va strictly real • imaginary parts: unitarization (cuts in in-med. QQ propagatorGQQ) • simultaneous treatment of: • - bound + scattering states • - quarkonia (QQ) + heavy-quark diffusion (Qq,g) -
2.2 Brueckner Theory of Heavy Quarks in QGP InputProcessOutputTest quark-no. susceptibility Q → Q 0-modes lattice data spectral fcts./ eucl. correlat. - 2-body potential QQ T-matrix - QQ evolution (rate equation) Qq T-matrix Quark selfenergy exp. data Q spectra + v2 (Langevin)
2.3 Free vs. Internal Energy in Lattice QCD F1(r,T) = U1(r,T) – T S1(r,T) Free Energy Internal Energy [Kaczmarek +Zantow ’05] - - • strong QQ potential,U = ‹Hint› • large mQ*~ mQ+ U1(∞,T)/2 • weak QQ potential • small mQ*~mQ+ F1(∞,T)/2 • F, U, Sthermodynamic quantities • Entropy: many-body effects
D - D J/y - c c J/y 3.) Quarkonium Transport in Heavy-Ion Collisions [PBM+Stachel ’00,Thews et al ’01, Grandchamp+RR ‘01, Gorenstein et al ’02, Ko et al ’02, Andronic et al ‘03, Zhuang et al ’05, Ferreiro et al ‘11, …] • Inelastic Reactions: • detailed balance: → - ← J/y + g c + c + X • Rate • Equation: • Thermal Input: Transport coefficients • - chemical relaxation rate Gy • - equililbrium limit Nyeq(eyB, mc* ,tceq) • Phenomenological Input: • - J/y,cc,y’+c,b initial distributions [pp, pA] • - space-time medium evolution [AA: hydro,...] Observables
3.1Thermal Charmonium Properties (a) EquilibriumYnumber: - • gc from fixed cc number: • interplay of mc* and • constrain spectral shape by • lattice-QCD correlators eyB mc* (b) Inelastic YWidth q q • controlled by as(parameter) Gy
3.2 Effect of Partial c-Quark Thermalization on J/y • Relaxation time ansatz: Nyeq (t) ~ Nytherm(t) · [1-exp(-t/tceq)] Microscopic Calculation Impact on Regeneration [Zhao ‘11] [Song,Han, Ko ‘12] • significant sensitivity of regeneration on charm-quark diffusion
3.2.2 D-Meson Thermalization at LHC A • to be determined…
4.1 Inclusive J/y at SPS + RHIC Strong Binding (U) Weak Binding (F) [Zhao+RR ‘10] • as~0.3, charm relax. tceq = 4(2) fm/c for U(F) vs. ~5(10) from T-matrix • different composition in two scenarios
4.1.2 J/y pT Spectra + Elliptic Flow at RHIC (U potential) • shallow minimum at low pT • high pT: • formation time, b feeddown, Cronin • small v2limits regeneration, • but does not exclude it
4.2.1 J/y at LHC: Centrality Dependence Mid-Rapidity Forward Rapidity • regeneration becomes dominant • uncertainties: sccbar, shadowing, … • transport approaches consistent [Zhao+RR ‘11]
4.2.2 J/y at LHC: pT-Spectra + v2 • low pT maximum confirms • expected regeneration level • b-feeddown prevalent at high pT • significant increase at mid-y [He et al ’12]
4.3 (1S) and (2S) at LHC Weak Binding Strong Binding (1S) → (2S) → [Grandchamp et al ’06, Emerick et al ‘11] • sensitive to color-screening + early evolution times • clear preference for strong binding (U potential) • similar results by [Strickland ‘12]
5.) Conclusions • Quarkonium discoveries at LHC: • - increase of J/yRAAover RHIC/SPS • - low-pT enhancement • - sizable v2 • - strong suppression of ’ (eB’~ eBJ/y) • Predicted signatures of QGP transport + hadronization • - controlled by quantitative description of RHIC+SPS data, lattice QCD • Implications • - Ti SPS(~240) < Tdiss(J/y,’) < TiRHIC (~350) < TiLHC(~550) ≤ Tdiss() • - confining force screened at RHIC+LHC • - marked recombination of diffusing charm quarks at LHC • Uncertainties • - input HF cross sections, HF thermalization • - initial-state effects (final-state in dAu, pPb?!)
q q 2.) Thermodynamic T-Matrix for Quarkonia in QGP • Lippmann-Schwinger equation In-Medium Q-QT-Matrix: - • potential Va strictly real • imaginary parts: unitarization (cuts in in-med. QQ propagatorGQQ) - • gluo-dissosciation (coupled channel) • [Bhanot+Peskin ‘85] • Landau damping (HQ selfenergy)
3.3.3 J/y at LHC III: High-pt – ATLAS+CMS [Zhao+RR ‘11] • underestimate for peripheral • (spherical fireball reduces surface effects …)
3.3.4 Time Evolution of J/y at LHC Strong Binding (U) Weak Binding (F) • finite “cooking-time” window, determined by inelastic width [Zhao+RR ‘11]
3.4 at RHIC and LHC Weak Binding Strong Binding RHIC → LHC → [Grandchamp et al ’06, Emerick et al ‘11] • sensitive to color-screening + early evolution times
3.2 Charmonia in QGP: T-Matrix Approach • U-potential, • selfconsist. c-quark width • Spectral Functions • - J/y melting at ~1.5Tc • - cc melting at ~Tc • - Gc ~ 100MeV • Correlator Ratios • - rough agreement with • lQCD within uncertainties [Aarts et al ‘07] [Mocsy+ Petreczky ’05+’08, Wong ’06, Cabrera+RR ’06, Beraudo et al ’06, Satz et al ’08, Lee et al ’09, Riek+RR ’10, …]
3.2.2 T-matrix Approach with F-Potential • selfcons. c-quark width • Spectral Functions • - J/y melting at ~1.1Tc • - cc melting at ≤ Tc • - Gc ~ 50MeV • Correlator Ratios • - slightly worse agreement • with lQCD [Aarts et al ‘07] [Riek+RR ’10]
3.3 Charm-Quark Susceptibility in QGP → 2 → G→ 0 m « T [Riek+RR ‘10] • sensitive to in-medium charm-quark mass • finite-width effects can compensate in-medium mass increase
4.2.5.2 Thermalization Rate from T-Matrix gc [1/fm] • thermalization 4 (2) times faster using U (F) as potential than pert. QCD • momentum dependence essential (nonpert. effect ≠ K-factor!) [Riek+RR ‘10]
_ 3.1.3 Momentum Dependence of Inelastic Width • dashed lines: gluo-dissociation • solid lines: quasifree dissociation • similar to full NLO calculation [Park et al ‘07] [Zhao+RR ‘07]
4.3 J/y at Forward Rapidity at RHIC [Zhao+ RR ‘10]