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arXiv · 1204.2388

Effect of spectral modification of $ρ$ on shear viscosity of a pion gas

Sukanya Mitra·Sabyasachi Ghosh·Sourav Sarkar
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Abstract

We evaluate the shear viscosity of a pion gas in the relativistic kinetic theory approach. The in-medium propagator of the $ρ$ meson at finite temperature is used to evaluate the $π-π$ scattering amplitude in the medium. The real and imaginary parts of the self-energy calculated from one-loop diagrams are seen to have noticeable effects on the scattering cross-section. The consequences on temperature dependence of the shear viscosity evaluated in the Chapman-Enskog and relaxation time approximations are studied.

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Sukanya Mitra, Sabyasachi Ghosh, Sourav Sarkar. 2012-06-28. Effect of spectral modification of $ρ$ on shear viscosity of a pion gas. https://doi.org/10.1103/physrevc.85.064917

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