Elliptic and hexadecupole flow from AGS to LHC energies

Using a hydrodynamic model we study the effects of the initial spatial anisotropy in non-central heavy-ion collisions on the momentum distributions of the emitted hadrons. We show that the elliptic flow measured at midrapidity in 158 $A$ GeV/$c$ Pb+Pb collisions can be quantitatively reproduced by hydrodynamic expansion, indicating early thermalization in the collision. We predict the excitation function of the elliptic and hexadecupole flow from AGS to LHC energies and discuss its sensitivity to the quark-hadron phase transition.