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arXiv · 1307.4681

Shear viscosity of hadrons with K-matrix cross sections

Anton Wiranata·Volker Koch·Madappa Prakash·Xin Nian Wang
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Abstract

Shear viscosity ηand entropy density s of a hadronic resonance gas are calculated using the Chapman-Enskog and virial expansion methods using the K-matrix parametrization of hadronic cross sections which preserves the unitarity of the T -matrix. In the π-K-N-η- mixture considered, a total of 57 resonances up to 2 GeV were included. Comparisons are also made to results with other hadronic cross sections such as the Breit-Wigner (BW) and, where available, experimental phase shift parametrizations. Hadronic interactions forming resonances are shown to decrease the shear viscosity and increase the entropy density leading to a substantial reduction of η/s as the QCD phase transition temperature is approached.

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Anton Wiranata, Volker Koch, Madappa Prakash, Xin Nian Wang. 2013-07-17. Shear viscosity of hadrons with K-matrix cross sections. https://doi.org/10.1103/physrevc.88.044917

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