Dissipative hydrodynamics coupled to chiral fields

Abstract

Using second-order dissipative hydrodynamics coupled self-consistently to the linear sigma model we study the 2 + 1 dimensional evolution of the fireball created in Au + Au relativistic collisions. We analyze the influence of the dynamics of the chiral fields on the charged-hadron elliptic flow nu(2) and on the ratio nu(4)/(nu(2))(2) for a temperature-independent as well as for a temperature-dependent viscosity-to-entropy ratio eta/s calculated from the linearized Boltzmann equation in the relaxation time approximation. We find that nu(2) is not very sensitive to the coupling of chiral sources to the hydrodynamic evolution, but the temperature dependence of eta/s plays a much bigger role on this observable. on the other hand, the ratio nu(4)/(nu(2))(2) turns out to be much more sensitive than nu(2) to both the coupling of the chiral sources and the temperature dependence of eta/s.