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Pion Properties in a Hot $ΠN Δ$ Gas

R. Rapp·J. Wambach
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Abstract

Based on a recent meson-exchange model for the vacuum $ππ$ interaction we compute selfconsistently the in-medium $ππ$ scattering amplitude and pion selfenergy in a hot $πNΔ$ gas. The contributions to the pion selfenergy are calculated from the $ππ$ T-matrix as well as from p-wave interaction with nucleons and thermally abundant $Δ$'s. Results are presented for two scenarios believed to be realized in the relativistic heavy ion collisions performed at the GSI-SIS and the CERN-SpS. Possible implications for the observed soft pion enhancement at both SIS and SpS are indicated.

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R. Rapp, J. Wambach. 1993-11-20. Pion Properties in a Hot $ΠN Δ$ Gas. https://doi.org/10.1016/0375-9474(94)90233-x

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