Shear viscosity (η) is a basic transport coefficient of the medium.In this work,we calculate shear viscosity to entropy density ratio (η/S) of an equilibrated system in intermediate energy heavy ion collisions withi...Shear viscosity (η) is a basic transport coefficient of the medium.In this work,we calculate shear viscosity to entropy density ratio (η/S) of an equilibrated system in intermediate energy heavy ion collisions within the framework of the Boltzmann-Uehling-Uhlenbeck model (BUU) model.After the equilibration of Au + Au system at central collision in a fixed volume is reached,temperature,pressure and energy density are extracted by the phase space information and then η/S is calculated using the Green-Kubo formulas.The results show that η/S drops with the incident energy and its value is not so drastically different from the RHIC results.展开更多
We studied the effect of isospin dependent momentum interaction(IDMI) on the isospin fractionation ratio and its dynamical mechanism by using the quantum molecular dynamics model in intermediate energy heavy ion colli...We studied the effect of isospin dependent momentum interaction(IDMI) on the isospin fractionation ratio and its dynamical mechanism by using the quantum molecular dynamics model in intermediate energy heavy ion collisions. Fig.1 shows the (N/Z)nucl/(N/Z)frag at freeze-out time as a function of the neutron-proton ratio of colliding system with MDI and IDMI for the reactions 94Kr+94Kr,94Zr+94Zr, 94Mo+94Mo and 94Ru+94Ru at a beam energy of 50 MeV/u and an impact parameter of 2.0 fm. There are the same mass 188 for展开更多
基金supported by the National Natural Science Foundation of China (No.11035009,10979074,10775168 and 10975174)Major State Basic Research Development Program in China (No.2007CB815004)+1 种基金Foundation for Developing Science and Technology in Shanghai (No. 09JC1416800)Knowledge Innovation Project of Chinese Academy ofSciences under (No. KJCX2-EW-N01)
文摘Shear viscosity (η) is a basic transport coefficient of the medium.In this work,we calculate shear viscosity to entropy density ratio (η/S) of an equilibrated system in intermediate energy heavy ion collisions within the framework of the Boltzmann-Uehling-Uhlenbeck model (BUU) model.After the equilibration of Au + Au system at central collision in a fixed volume is reached,temperature,pressure and energy density are extracted by the phase space information and then η/S is calculated using the Green-Kubo formulas.The results show that η/S drops with the incident energy and its value is not so drastically different from the RHIC results.
文摘We studied the effect of isospin dependent momentum interaction(IDMI) on the isospin fractionation ratio and its dynamical mechanism by using the quantum molecular dynamics model in intermediate energy heavy ion collisions. Fig.1 shows the (N/Z)nucl/(N/Z)frag at freeze-out time as a function of the neutron-proton ratio of colliding system with MDI and IDMI for the reactions 94Kr+94Kr,94Zr+94Zr, 94Mo+94Mo and 94Ru+94Ru at a beam energy of 50 MeV/u and an impact parameter of 2.0 fm. There are the same mass 188 for