$J/\psi$ production and elliptic flow in relativistic heavy-ion collisions

Abstract

Using a two-component model for charmonium production, which includes contributions from both the initial hard nucleon-nucleon scattering and from the regeneration in the quark-gluon plasma, we study the nuclear modification factor $R_{AA}$ and elliptic flow $v_2$ of $J/\psi$ in relativistic heavy ion collisions. For the expansion dynamics of produced hot dense matter, we introduce a schematic fireball model with its transverse acceleration determined from the pressure gradient inside the fireball and azimuthally anisotropic expansion parameterized to reproduce measured $v_2$ of light hadrons. We assume that light hadrons freeze out at the temperature of 120 MeV while charmonia at 160 MeV, similar to the kinetic and chemical freeze-out temperatures in the statistical model, respectively. For the properties of charmonia in the quark-gluon plasma, we use the screening mass between their charm and anticharm quarks and their dissociation cross sections given by the perturbative QCD (pQCD) in the leading order and up to the next-to-leading order, respectively. For the relaxation time of charm and anticharm quarks in the quark-gluon plasma, we also use the one calculated in the leading order of pQCD. Modeling the effect of higher-order corrections in pQCD by introducing multiplicative factors to the dissociation cross section of charmonia and the elastic scattering cross sections of charm and anticharm quarks, we find that this effect is small for the $R_{AA}$ of $J/\psi$ as they suppress the number of initially produced $J/\psi$ but enhance the number of regenerated ones. The higher-order corrections increase, however, the $v_2$ of $J/\psi$. Our results suggest that the $v_2$ of $J/\psi$ can play an important role in discriminating between $J/\psi$ production from the initial hard collisions and from the regeneration in the quark-gluon plasma.

15 pages, 14 figures

References in corpus (13)

• Energy Loss and Flow of Heavy Quarks in Au+Au Collisions at sqrt(s_NN) = 200 GeV
• J/psi Production vs Centrality, Transverse Momentum, and Rapidity in Au+Au Collisions at sqrt(s_NN) = 200 GeV
• Statistical hadronization of heavy quarks in ultra-relativistic nucleus-nucleus collisions
• J/psi Production vs Transverse Momentum and Rapidity in p+p Collisions at sqrt(s) = 200 GeV
• J/psi Production in Quark-Gluon Plasma
• Transverse Momentum Spectra of J/ψin Heavy-Ion Collisions
• Elliptic flow for phi mesons and (anti)deuterons in Au+Au collisions at sqrt(s_NN) = 200 GeV
• Mass Shift and Width Broadening of J/psi in hot gluonic plasma from QCD Sum Rules
• The widths of quarkonia in quark gluon plasma
• The thermal width of heavy quarkonia moving in quark gluon plasma
• $R_{AA}$ of $J/\psi$ near mid-rapidity in heavy ion collisions at $\sqrt{s_{NN}}=200$ GeV
• J/$\psi$ suppression in In-In collisions at 158 GeV/nucleon
• Negative Elliptic Flow of $J/\psi$'s: A Qualitative Signature for Charm Collectivity at RHIC

Cited by in corpus (5)

• Dilepton production in proton-proton and Pb+Pb collisions at sqrt(s_NN)=2.76 TeV
• Dilepton production in a schematic causal viscous hydrodynamics
• Quarkonium formation time in relativistic heavy-ion collisions
• Quarkonium formation time in quark-gluon plasma
• Charmonium in Hot Medium