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arXiv · 1006.0257

Quasi-Particle Theory of Shear and Bulk Viscosities of Hadronic Matter

P. Chakraborty·J. I. Kapusta
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Abstract

A theoretical framework for the calculation of shear and bulk viscosities of hadronic matter at finite temperature is presented. The framework is based on the quasi-particle picture. It allows for an arbitrary number of hadron species with point-like interactions, and allows for both elastic and inelastic collisions. Detailed balance is ensured. The particles have temperature dependent masses arising from mean field or potential effects, which maintains self-consistency between the equation of state and the transport coefficients. As an example, we calculate the shear and bulk viscosity in the linear $\sigma$ model. The ratio of shear viscosity to entropy density shows a minimum in the vicinity of a rapid crossover transition, while the ratio of bulk viscosity to entropy density shows a maximum.

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P. Chakraborty, J. I. Kapusta. 2010-06-01. Quasi-Particle Theory of Shear and Bulk Viscosities of Hadronic Matter. https://doi.org/10.1103/physrevc.83.014906

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