Bulk viscosity effects on elliptic flow

The effects of bulk viscosity on the elliptic flow $v_2$ are studied using realistic equation of state and realistic transport coefficients. We find that thebulk viscosity acts in a non trivial manner on $v_2$. At low $p_T$, the reduction of $v_2$ is even more effective compared to the case of shear viscosity, whereas at high $p_T$, an enhancement of $v_2$ compared to the ideal case is observed. We argue that this is caused by the competition of the critical behavior of the equation of state and the transport coefficients.