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arXiv · 1303.6408

Medium effects on the viscosities of a pion gas

Sukanya Mitra·Sourav Sarkar
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Abstract

The bulk and shear viscosities of a pion gas is obtained by solving the relativistic transport equation in the Chapman-Enskog approximation. In-medium effects are introduced in the $ππ$ cross-section through one-loop self-energies in the propagator of the exchanged $ρ$ and $σ$ mesons. The effect of early chemical freeze-out in heavy ion collisions is implemented through a temperature dependent pion chemical potential. These are found to affect the temperature dependence of the bulk and shear viscosities significantly.

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Sukanya Mitra, Sourav Sarkar. 2013-05-29. Medium effects on the viscosities of a pion gas. https://doi.org/10.1103/physrevd.87.094026

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