Anisotropic-hydrodynamics approach to a quark-gluon fluid mixture

The anisotropic-hydrodynamics framework is used to describe a mixture of quark and gluon fluids. The effects of quantum statistics, finite quark mass, and finite baryon number density are taken into account. The results of anisotropic hydrodynamics are compared with exact solutions of the coupled kinetic equations for quarks and gluons in the relaxation time approximation. An overall very good agreement between the hydrodynamic and kinetic-theory results is found.

Figure 1

Proper-time dependence of the effective temperature $T$, panel (a), and the effective baryon chemical potential $\mu$ divided by $T$, panel (b), both rescaled by the initial values. The exact kinetic-theory result (KT, orange solid line) is compared with the aHydro (double-dot-dashed line), Navier-Stokes (NS, blue dashed line), and perfect-fluid (BJ, green dot-dashed line) results, respectively. The label “qs” denotes using the quantum statistics for both quarks and gluons.

Figure 2

Proper-time dependence of the transverse pressure over energy density ratio $[{\mathcal{P}}_T/\mathcal{E}$, panels (a) and (b)] and the longitudinal pressure over transverse pressure ratio $[{\mathcal{P}}_L/{\mathcal{P}}_T$, panels (c) and (d)] for the initial oblate-oblate configuration. Notation is the same as in Fig. 1.

Figure 3

Same as Fig. 2 but for the prolate-prolate initial configuration.