Heavy Quarks in Heavy-Ion Collisions

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1 Heavy Quarks in Heavy-Ion Collisions Hendrik van Hees with T. Lang, J. Steinheimer, M. Bleicher Goethe University Frankfurt and FIAS July 18, 213 Hendrik van Hees (GU Frankfurt/FIAS) Heavy Quarks in HICs July 18, / 15

2 Outline 1 Heavy-quark interactions in the sqgp Heavy quarks in heavy-ion collisions Heavy-quark diffusion: The Langevin Equation 2 Non-perturbative HQ interactions Resonance model for HQ-q Scattering T-matrix approach with lqcd potentials 3 Comparison with data Nonphotonic electrons at RHIC D mesons at LHC Predictions for D mesons at FAIR Dileptons from correlated D D decays 4 Summary and Outlook Hendrik van Hees (GU Frankfurt/FIAS) Heavy Quarks in HICs July 18, / 15

3 Motivation Fast equilibration of hot and dense matter in heavy-ion collisions: collective flow (nearly ideal hydrodynamics) sqgp Heavy quarks as calibrated probe of QGP properties produced in early hard collisions: well-defined initial conditions not fully equilibrated due to large masses heavy-quark diffusion probes for QGP-transport properties Langevin simulation within UrQMD-hydro hybrid model drag and diffusion coefficients T-matrix approach with static lattice-qcd heavy-quark potentials resonance formation close to T c mechanism for non-perturbative strong interactions Hendrik van Hees (GU Frankfurt/FIAS) Heavy Quarks in HICs July 18, / 15

4 Heavy Quarks in Heavy-Ion collisions c q g hard production of HQs described by PDF s + pqcd (PYTHIA) c,b quark sqgp HQ rescattering in QGP: Langevin simulation drag and diffusion coefficients from microscopic model for HQ interactions in the sqgp q c Hadronization to D,B mesons via quark coalescence + fragmentation K ν e e ± semileptonic decay non-photonic electron observables R e+ e AA (p T), v e+ e 2 (p T ) Hendrik van Hees (GU Frankfurt/FIAS) Heavy Quarks in HICs July 18, / 15

5 Relativistic Langevin process Langevin process: friction force + Gaussian random force in the (local) rest frame of the heat bath d x = p dt, E p d p = A p dt + 2dt[ B P + B 1 P ] w w: normal-distributed random variable A: friction (drag) coefficient B,1 : diffusion coefficients Einstein dissipation-fluctuation relation B 1 = E p TA. flow via Lorentz boosts between heat-bath frame and lab frame A and B from microscopic models for qq, gq scattering background medium: UrQMD hydro UrQMD Hendrik van Hees (GU Frankfurt/FIAS) Heavy Quarks in HICs July 18, / 15

6 Non-perturbative interactions: Resonance Scattering General idea: Survival of D- and B-meson like resonances above T c model based on chiral symmetry (light quarks) HQ-effective theory elastic heavy-light-(anti-)quark scattering q c q c c D, D, D s s q c u D, D, D s q D- and B-meson like resonances in sqgp q D, D, D s D, D, D s parameters m D = 2 GeV, Γ D = GeV m B = 5 GeV, Γ B = GeV k c k Hendrik van Hees (GU Frankfurt/FIAS) Heavy Quarks in HICs July 18, / 15

7 T-matrix Brueckner many-body approach for elastic Qq, Q q scattering q, q c T = V + V T Σ = Σ glu + T V: static q q potential from lattice QCD (F and U) reduction scheme: 4D Bethe-Salpeter 3D Lipmann-Schwinger S- and P waves Relation to invariant matrix elements ( ) M(s) 2 d a T a,l= (s) T a,l=1 (s) 2 cos θ cm q Hendrik van Hees (GU Frankfurt/FIAS) Heavy Quarks in HICs July 18, / 15

8 T-matrix results -Im T (GeV -2 ) T=1.2 T c T=1.5 T c T=2 T c c quarks T-Matrix with V=U Kac color-singlet channel E cm (GeV) resonance formation at lower temperatures T T c melting of resonances at higher T model-independent assessment of elastic Qq, Q q scattering! Hendrik van Hees (GU Frankfurt/FIAS) Heavy Quarks in HICs July 18, / 15

9 Nonphotonic electrons at RHIC form D and B mesons via quark-antiquark coalescence use PYTHIA for semi-leptonic decays comparison to single-electron data from PHENIX (2 AGeV Au-Au collisions) electrons Au+Au - 2 GeV Centrality 2%-4% HF electrons PHENIX Resonance 13MeV Resonance 15MeV Resonance 18MeV T-Matrix 18MeV Coalescence.2.15 electrons Au+Au - 2 GeV Centrality 2%-4% HF electrons PHENIX Resonance 13MeV Resonance 15MeV Resonance 18MeV T-Matrix 18MeV Coalescence R AA 1 v [T. Lang, HvH, J. Steinheimer, M. Bleicher, arxiv: [hep-ph]] Hendrik van Hees (GU Frankfurt/FIAS) Heavy Quarks in HICs July 18, / 15

10 D mesons at LHC form D via quark-antiquark coalescence comparison to D-meson data from ALICE (2.76 ATeV Pb-Pb collisions) R AA ALICE pompt D-mesons -2% UrQMD D-Mesons -2% Pb+Pb, s 1/2 = 2.76 TeV [T. Lang, HvH, J. Steinheimer, M. Bleicher, arxiv: [hep-ph]] v electrons Au+Au - 2 GeV Centrality 2%-4% HF electrons PHENIX Resonance 13MeV Resonance 15MeV Resonance 18MeV T-Matrix 18MeV Coalescence Hendrik van Hees (GU Frankfurt/FIAS) Heavy Quarks in HICs July 18, / 15

11 D mesons at FAIR R AA form D via quark-antiquark coalescence large sensitivity to initial HQ distributions (use estimates from HSD and PYTHIA) D-Mesons PbPb - 25 AGeV y <.35 HSD initial -1% 1-2% 2-4% 4-6% 6-92% no fugacity [T. Lang, HvH, J. Steinheimer, M. Bleicher, arxiv: [hep-ph]] R AA D-Mesons PbPb - 25 AGeV y <.35 PHYTIA initial -1% 1-2% 2-4% 4-6% 6-92% no fugacity Hendrik van Hees (GU Frankfurt/FIAS) Heavy Quarks in HICs July 18, / 15

12 D mesons at FAIR form D via quark-antiquark coalescence large sensitivity to initial HQ distributions (use estimates from HSD and PYTHIA) v D-Mesons PbPb - 25 AGeV y <.35 HSD initial -1% 1-2% 2-4% 4-6% 6-92% no fugacity v D-Mesons PbPb - 25 AGeV y <.35 PYTHIA initial -1% 1-2% 2-4% 4-6% 6-92% no fugacity [T. Lang, HvH, J. Steinheimer, M. Bleicher, arxiv: [hep-ph]] Hendrik van Hees (GU Frankfurt/FIAS) Heavy Quarks in HICs July 18, / 15

13 D mesons at FAIR form D via quark-antiquark coalescence large sensitivity to initial HQ distributions (use estimates from HSD and PYTHIA) large µ B in resonance model: c more dragged than c Pb+Pb - 25 AGeV Centrality 2%-4% y <.35 HSD initial no fugacity anti-d-mesons D-mesons w/fugacity.2.15 Pb+Pb - 25 AGeV Centrality 2%-4% y <.35 HSD initial no fugacity anti-d-mesons D-mesons w/fugacity R AA 4 3 v [T. Lang, HvH, J. Steinheimer, M. Bleicher, arxiv: [hep-ph]] Hendrik van Hees (GU Frankfurt/FIAS) Heavy Quarks in HICs July 18, / 15

14 Dileptons from correlated D D decays for m φ M l + l m J/ψ: dilepton emission from thermal QGP and from correlated D D decays medium modifications of D and D destroy correlations dn/dm[1/(gev/c 2 )] e-5 1e-6 1e-7 [T. Lang, HvH, J. Steinheimer, M. Bleicher, arxiv: [hep-ph]] min.bias Au+Au 2 GeV PYTHIA pp random correlation PHENIX UrQMD physical thermalization UrQMD extreme thermalization UrQMD no interaction M ee [GeV/c 2 ] Hendrik van Hees (GU Frankfurt/FIAS) Heavy Quarks in HICs July 18, / 15

15 Summary and Outlook Heavy quarks in the sqgp non-perturbative interactions mechanism for strong coupling: resonance formation at T T c lattice-qcd potentials parameter free also provides natural mechanism for quark coalescence Comparison to data and predictions for FAIR R AA and v 2 of non-photonic electrons at RHIC R AA and v 2 for D mesons at LHC R AA and v 2 for D mesons at FAIR (pp baseline mandatory!) impact of medium modifications on correlated D D decays to dileptons Outlook implementation of hadronic cross sections for D/B-meson diffusion include inelastic heavy-quark processes (gluo-radiative processes) implement resonance-recombination model for hadronization charmonium/bottomonium suppression/regeneration Hendrik van Hees (GU Frankfurt/FIAS) Heavy Quarks in HICs July 18, / 15

Heavy flavor with

Heavy flavor with CBM@FAIR Hendrik van Hees Goethe University Frankfurt and FIAS April 21, 2015 Hendrik van Hees (GU Frankfurt/FIAS) Heavy flavor with CBM@FAIR April 21, 2015 1 / 22 Outline 1 Motivation: