"Figure 2.5" of "Measurements of Higher-Order Flow Harmonics in Au+Au Collisions at sqrt(s_NN) = 200 GeV"

Flow coefficients $v_n$ for $n$ = 2, 3, 4, characterizing the anisotropic collective flow in Au+Au collisions at $\sqrt{s_{NN}}~=~200$ GeV, are measured relative to event planes $\Psi_{n}$, determined at large rapidity. We report $v_n$ as a function of transverse momentum and collision centrality, and study the correlations among the event planes of different order $n$. The $v_n$ are well described by hydrodynamic models which employ a Glauber Monte Carlo initial state geometry with fluctuations, providing additional constraining power on the interplay between initial conditions and the effects of viscosity as the system evolves. This new constraint can serve to improve the precision of the extracted shear viscosity to entropy density ratio $\eta/s$.