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Thermal Properties of a Hot Pion Gas beyond the Quasiparticle Approximation

R. Rapp·J. Wambach
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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 $ππ$ 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 $ππ$ interaction in a chirally improved version of the Jülich $ππ$ model.

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R. Rapp, J. Wambach. 1995-02-09. Thermal Properties of a Hot Pion Gas beyond the Quasiparticle Approximation. https://doi.org/10.1016/0370-2693(95)00361-n

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