Toward a solution to the $R_{AA}$ and $v_2$ puzzle for heavy quarks

Abstract

The heavy quarks constitutes a unique probe of the quark-gluon plasma properties. Both at RHIC and LHC energies a puzzling relation between the nuclear modification factor $R_{AA}(p_T)$ and the elliptic flow $v_2(p_T)$ has been observed which challenged all the existing models, especially for D mesons. We discuss how the temperature dependence of the heavy quark drag coefficient is responsible for a large part of such a puzzle. In particular, we have considered four different models to evaluate the temperature dependence of drag and diffusion coefficients propagating through a quark gluon plasma (QGP). All the four different models are set to reproduce the same $R_{AA}(p_T)$ observed in experiments at RHIC and LHC energy. We point out that for the same $R_{AA}(p_T)$ one can generate 2-3 times more $v_2$ depending on the temperature dependence of the heavy quark drag coefficient. A non-decreasing drag coefficient as $T\to T_c$ is a major ingredient for a simultaneous description of $R_{AA}(p_T)$ and $v_2(p_T)$.

7 pages, 6 figures, Accepted for publication in Physics Letters B

References in corpus (17)

• The QCD equation of state with dynamical quarks
• Energy Loss and Flow of Heavy Quarks in Au+Au Collisions at sqrt(s_NN) = 200 GeV
• Nonperturbative Heavy-Quark Diffusion in the Quark-Gluon Plasma
• Towards an understanding of the RHIC single electron data
• Coalescence Models For Hadron Formation From Quark Gluon Plasma
• ${\mathbf{D}}_{\mathbf{s}}$-Meson as Quantitative Probe of Diffusion and Hadronization in Nuclear Collisions
• Heavy-flavour spectra in high energy nucleus-nucleus collisions
• Open heavy flavor in Pb+Pb collisions at sqrt(s)=2.76 TeV within a transport model
• Collisional dissociation of heavy mesons in dense QCD matter
• Comparing the drag force on heavy quarks in N=4 super-Yang-Mills theory and QCD
• Angular Dependence of Jet Quenching Indicates Its Strong Enhancement Near the QCD Phase Transition
• Heavy Quark Diffusion with Relativistic Langevin Dynamics in the Quark-Gluon Fluid
• Charm elliptic flow at RHIC
• Scalings of Elliptic Flow for a Fluid at Finite Shear Viscosity
• Dynamical collisional energy loss and transport properties of on- and off-shell heavy quarks in vacuum and in the Quark Gluon Plasma
• Transport coefficients of heavy quarks around $T_c$ at finite quark chemical potential
• Testing AdS/CFT Drag and pQCD Heavy Quark Energy Loss

Cited by in corpus (5)

• A data-driven analysis for the temperature and momentum dependence of the heavy quark diffusion coefficient in relativistic heavy-ion collisions
• SQM2016: Theory Summary
• Heavy flavor $R_{\text{AA}}$ and $v_n$ in event-by-event viscous relativistic hydrodynamics
• Nuclear modification and azimuthal anisotropy of D mesons produced in relativistic heavy ion collision
• Heavy quark dynamics in QCD matter