Thermal Properties of a Hot Pion Gas beyond the Quasiparticle Approximation
arXiv:nucl-th/9502023 · doi:10.1016/0370-2693(95)00361-N
Abstract
Within the Matsubara formalism we derive expressions for the pion self-energy and the two-pion propagator in a hot pion gas. These quantities are used to selfconsistently calculate the in-medium $ÏÏ$ amplitude beyond the quasiparticle approximation (QPA). The results are shown to differ significantly from QPA-based calculations. We also examine the impact of chiral constraints on the $ÏÏ$ interaction in a chirally improved version of the Jülich $ÏÏ$ model.
12 pages LaTex (3 figures uuencoded)