Ratio of shear viscosity to entropy density in multifragmentation of Au + Au
1 Shanghai Institute of Applied Physics, Chinese Academy of Sciences - Shanghai 201800, China
2 Graduate School of the Chinese Academy of Sciences - Beijing 100080, China
Received: 22 March 2012
Accepted: 25 May 2012
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 (1/4π). 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.
PACS: 66.20.-d – Viscosity of liquids; diffusive momentum transport / 25.70.-z – Low and intermediate energy heavy-ion reactions
© EPLA, 2012