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arXiv · 1107.2842

Shear viscosity to entropy density ratio in the Boltzmann-Uehling-Uhlenbeck model

S. X. Li·D. Q. Fang·Y. G. Ma·C. L. Zhou
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Abstract

The ratio of shear viscosity ($η$) to entropy density ($s$) for an equilibrated system is investigated in intermediate energy heavy ion collisions below 100$A$ MeV within the framework of the Boltzmann-Uehling-Uhlenbeck (BUU) model . After the collision system almost reaches a local equilibration, the temperature, pressure and energy density are obtained from the phase space information and {$η/s$} is calculated using the Green-Kubo formulas. The results show that {$η$}/$s$ decreases with incident energy and tend towards a smaller value around 0.5, which is not so drastically different from the BNL Relativistic Heavy Ion Collider results in the present model.

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S. X. Li, D. Q. Fang, Y. G. Ma, C. L. Zhou. 2011-08-11. Shear viscosity to entropy density ratio in the Boltzmann-Uehling-Uhlenbeck model. https://doi.org/10.1103/physrevc.84.024607

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