Transport coefficients of chiral fluid dynamics using low-energy effective models

Abstract

We investigate the first-order transport coefficients of a fluid made of quasiparticles with a temperature-dependent mass extracted from chiral models. We describe this system using an effective kinetic theory, given by the relativistic Boltzmann equation coupled to a temperature-dependent background field determined from the thermal masses. We then simplify the collision term using the relaxation time approximation and implement a Chapman-Enskog expansion to calculate all first-order transport coefficients. In particular, we compute the bulk and shear viscosities using thermal masses extracted from the linear sigma model coupled with constituent quarks and the NJL model.

Figures (19)

• Figure 1: Thermal effective quark mass as a function of the temperature for the LSMq and NJL models.
• Figure 2: Background field $B$ as a function of the temperature for the LSMq.
• Figure 3: Background field $B$ as a function of temperature for the NJL model.
• Figure 4: Pressure, energy density and entropy as functions of the temperature for LSMq.
• Figure 5: Pressure, energy density and entropy as functions of the temperature for the NJL model.