Medium effects on the thermal conductivity of a hot pion gas

Abstract

We investigate the effect of the medium on the thermal conductivity of a pion gas out of chemical equilibrium by solving the relativistic transport equation in the Chapman-Enskog and relaxation time approximations. Using an effective model for the $\ensuremath{\pi}\ensuremath{\pi}$ cross section involving $\ensuremath{\rho}$ and $\ensuremath{\sigma}$ meson exchange, medium effects are incorporated through thermal one-loop self-energies. The temperature dependence of the thermal conductivity is observed to be significantly affected.