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arXiv · 1709.02902

Shear viscosity of a pion gas due to $\rho\pi\pi$ and $\sigma\pi\pi$ interactions

Sabyasachi Ghosh·Gastao Krein·Saurav Sarkar
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Abstract

We have calculated the shear viscosity of pion medium, where propagating pion has some finite thermal width due to interaction with the low mass resonances, $\sigma$ and $\rho$. With the help of standard thermal field theoretical technique, the thermal width of the pion has been calculated from the pion self-energy diagram for $\pi\sigma$ and $\pi\rho$ loops, where an effective Lagrangian density has been used for interaction part. We have found a very small value of shear viscosity by entropy density ratio ($\eta/s$), which is very close to the KSS bound.

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Sabyasachi Ghosh, Gastao Krein, Saurav Sarkar. 2017-09-09. Shear viscosity of a pion gas due to $\rho\pi\pi$ and $\sigma\pi\pi$ interactions. https://arxiv.org/abs/1709.02902

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