Initial eccentricity fluctuations and their relation to higher-order flow harmonics

Abstract

Monte Carlo simulations are used to compute the centrality dependence of the participant eccentricities ($\epsilon_{n}$) in Au+Au collisions, for the two primary models currently employed for eccentricity estimates -- the Glauber and the factorized Kharzeev-Levin-Nardi (fKLN) models. They suggest specific testable predictions for the magnitude and centrality dependence of the flow coefficients $v_n$, respectively measured relative to the event planes $\Psi_n$. They also indicate that the ratios of several of these coefficients may provide an additional constraint for distinguishing between the models. Such a constraint could be important for a more precise determination of the specific viscosity of the matter produced in heavy ion collisions.