Elliptic flow at energies available at the CERN Large Hadron Collider: Comparing heavy-ion data to viscous hydrodynamic predictions

Abstract

I compare the first viscous hydrodynamic prediction for integrated elliptic flow in Pb-Pb collisions at the LHC with the first data released by the ALICE collaboration. These new data are found to be consistent with hydrodynamic extrapolations of RHIC data with no change in medium parameters (e.g., average viscosity). I also discuss how, in general, a precise comparison of data to theoretical calculations requires an understanding of some subtleties of the measurement -- most notably the cut on transverse momentum of the particles used and the differing sensitivities to flow fluctuations and non-flow effects of the various measurement methods.

3 pages, 3 figures; v2: added plots of charged hadron multiplicity and identified particle differential elliptic flow, and a few minor changes

References in corpus (7)

• Effect of flow fluctuations and nonflow on elliptic flow methods
• Eccentricity fluctuations and elliptic flow at RHIC
• Elliptic flow in U+U collisions at sqrt{s_{NN}} = 200 GeV and in Pb+Pb collisions at sqrt{s_{NN}} = 2.76 TeV: Prediction from a hybrid approach
• Hydrodynamic radial and elliptic flow in heavy-ion collisions from AGS to LHC energies
• Soft heavy-ion physics from hydrodynamics with statistical hadronization - predictions for the Large Hadron Collider
• Elliptic flow in nuclear collisions at the Large Hadron Collider
• Multiplicity, mean $p_T$, $p_T$-spectra and elliptic flow of identified particles in Pb+Pb collisions at LHC

Cited by in corpus (2)

• The stickiness of sound: An absolute lower limit on viscosity and the breakdown of second order relativistic hydrodynamics
• Elliptic flow in Pb+Pb collisions at sqrt{s_{NN}} = 2.76 TeV: hybrid model assessment of the first data