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arXiv · 1206.6694

Ratio of shear viscosity to entropy density in multifragmentation of Au + Au

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

The ratio of the shear viscosity ($η$) to entropy density ($s$) for the intermediate energy heavy-ion collisions has been calculated by using the Green-Kubo method in the framework of the quantum molecular dynamics model. The theoretical curve of $η/s$ as a function of the incident energy for the head-on Au+Au collisions displays that a minimum region of $η/s$ has been approached at higher incident energies, where the minimum $η/s$ value is about 7 times Kovtun-Son- Starinets (KSS) bound (1/4$π$). We argue that the onset of minimum $η/s$ region at higher incident energies corresponds to the nuclear liquid gas phase transition in nuclear multifragmentation.

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C. L. Zhou, Y. G. Ma, D. Q. Fang, S. X. Li, G. Q. Zhang. 2012-06-28. Ratio of shear viscosity to entropy density in multifragmentation of Au + Au. https://doi.org/10.1209/0295-5075%2F98%2F66003

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