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Selfconsistent Description of a Thermal Piongas

R. Rapp·J. Wambach
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Abstract

We examine a hot pion gas by including medium modifications of the two-body scattering amplitude as well as mean-field effects selfconsistently. In contrast to earlier calculations, the in-medium T-matrix is rather close to the free one while the mean-field potential agrees well with lowest-order estimates. We also discuss the validity of the quasiparticle approximation. It is found that it is reliable for temperatures up to $\sim 150$ MeV. Above this temperature off-shell effects in the pion selfenergy become important, especially if the pions are strongly out of chemical equilibrium.

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R. Rapp, J. Wambach. 1993-06-16. Selfconsistent Description of a Thermal Piongas. https://doi.org/10.1016/0370-2693(93)91604-l

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