Initial indications for the production of a strongly coupled plasma in Pb+Pb collisions at $\sqrt{s_{NN}} = 2.76$ TeV

TL;DR

This study presents initial measurements of elliptic flow in Pb+Pb collisions at 2.76 TeV, showing strong similarities to results at lower energies and suggesting comparable quark-gluon plasma properties.

Contribution

First measurements of charged particle elliptic flow in Pb+Pb collisions at LHC, comparing results to RHIC data to explore QGP properties at higher energies.

Findings

Excellent agreement in flow coefficients between LHC and RHIC data.

Similar averaged specific viscosity of QGP at LHC and RHIC energies.

Elliptic flow trends indicate strongly coupled QGP at LHC.

Abstract

Results from first measurements of charged particle differential elliptic flow, obtained in Pb+Pb collisions at $\sqrt{s_{NN}} = 2.76$ TeV with the ALICE detector at CERN's Large Hadron Collider (LHC), are compared to those obtained for Au+Au collisions at $\sqrt{s_{NN}} = 0.2$ TeV with the PHENIX detector at BNL's Relativistic Heavy Ion Collider (RHIC). The comparisons, made as a function of centrality (cent) or the number of participant pairs ($N_{\text{part}}$) and particle transverse momentum $p_T$, indicate an excellent agreement between the magnitude and trends for the flow coefficients ${v_2(p_T,\text{cent})}$. Analysis indicates that the averaged specific viscosity of the quark gluon plasma (QGP) produced in LHC collisions, is similar to that for the strongly coupled QGP produced in RHIC collisions.