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arXiv · 1411.2765

Shear Viscosity and Phase Diagram from Polyakov$-$Nambu$-$Jona-Lasinio model

Sanjay K. Ghosh·Sibaji Raha·Rajarshi Ray·Kinkar Saha·Sudipa Upadhaya
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Abstract

We discuss a detailed study of the variation of shear viscosity, $η$, with temperature and baryon chemical potential within the framework of Polyakov$-$Nambu$-$Jona-Lasinio model. $η$ is found to depend strongly on the spectral width of the quasi-particles present in the model. The variation of $η$ across the phase diagram has distinctive features for different kinds of transitions. These variations have been used to study the possible location of the Critical End Point (CEP), and cross-checked with similar studies of variation of specific heat. Finally using a parameterization of freeze-out surface in heavy-ion collision experiments, the variation of shear viscosity to entropy ratio has also been discussed as a function of the center of mass energy of collisions.

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Sanjay K. Ghosh, Sibaji Raha, Rajarshi Ray, Kinkar Saha, Sudipa Upadhaya. 2014-11-12. Shear Viscosity and Phase Diagram from Polyakov$-$Nambu$-$Jona-Lasinio model. https://doi.org/10.1103/physrevd.91.054005

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