The centrality dependence of v2/epsilon: the ideal hydro limit and eta/s

Abstract

The large elliptic flow observed at RHIC is considered to be evidence for almost perfect liquid behavior of the strongly coupled quark-gluon plasma produced in the collisions. In these proceedings we present a two parameter fit for the centrality dependence of the elliptic flow scaled by the spatial eccentricity. We show by comparing to viscous hydrodynamical calculations that these two parameters are in good approximation proportional to the shear viscosity over entropy ratio and the ideal hydro limit of the ratio v2/epsilon.

4 pages, 8 figures - To appear in the conference proceedings for Quark Matter 2009, March 30 - April 4, Knoxville, Tennessee - final version without line numbers

References in corpus (5)

• Viscosity in Strongly Interacting Quantum Field Theories from Black Hole Physics
• Multiplicity scaling in ideal and viscous hydrodynamics
• The centrality dependence of elliptic flow, the hydrodynamic limit, and the viscosity of hot QCD
• The eccentricity in heavy-ion collisions from Color Glass Condensate initial conditions
• Collective phenomena in non-central nuclear collisions

Cited by in corpus (16)

• Elliptic flow of charged particles in Pb-Pb collisions at 2.76 TeV
• Elliptic Flow: A Brief Review
• Initial eccentricity fluctuations and their relation to higher-order flow harmonics
• v4 from ideal and viscous hydrodynamic simulations of nuclear collisions at the BNL Relativistic Heavy Ion Collider (RHIC) and the CERN Large Hadron Collider (LHC)
• Constraining the viscous freeze-out distribution function with data obtained at the BNL Relativistic Heavy Ion Collider (RHIC)
• Quark-Gluon Plasma at RHIC and the LHC: Perfect Fluid too Perfect?
• Viscosity from elliptic flow: the path to precision
• Experimental Determination of $\eta$/$s$ for Finite Nuclear Matter
• Phenomenology of the little bang
• Quantitative and Conceptual Considerations for Extracting the Knudsen Number in Heavy Ion Collisions
• Initial indications for the production of a strongly coupled plasma in Pb+Pb collisions at $\sqrt{s_{NN}}=2.76$ TeV
• Glauber-based evaluations of the odd moments of the initial eccentricity relative to the even order participant planes
• Knudsen number, ideal hydrodynamic limit for elliptic flow and QGP viscosity in $\sqrt{s}$=62 and 200 GeV Cu+Cu/Au+Au collisions
• Feeding of the elliptic flow by hard partons
• Puzzles, Progress, Prospects: pre-Summary for the Quark Matter 2009 Conference
• Causal dissipative hydrodynamics for heavy ion collisions