Temperature dependence of the QGP viscosity over entropy ratio from hydrodynamical analysis of ALICE data in = 2.76 TeV Pb + Pb collisions

Abstract

Within Israel–Stewart's theory of dissipative hydrodynamics, we have analyzed ALICE data for the centrality dependence of charged particle multiplicity, elliptic flow and pT spectra in = 2.76 TeV Pb + Pb collisions and obtained the temperature dependence of the QGP viscosity over the entropy ratio . If temperature dependence of is parameterized as , experimental data favor α in the range 0–0.2. α ⩾ 0.4 is not favored by the data. Experimental data in = 200 GeV Au + Au collisions however, prefer α = 0.4.