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arXiv · 1101.5661

Non-equilibrium dynamics in heavy ion collisions at low SIS energies

Qingfeng Li·Caiwan Shen·Chenchen Guo·Yongjia Wang·Zhuxia Li·J. Lukasik·W. Trautmann
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Abstract

The Ultrarelativistic Quantum Molecular Dynamics (UrQMD) model, a microscopic transport model, is used to study the directed and elliptic collective flows and the nuclear stopping in Au+Au collisions at incident energies covered by INDRA and lower-energy FOPI experiments. It is seen clearly that these observables are sensitive to both, the potential terms (including iso-scalar and iso-vector parts as well as the momentum dependent term) in the equation of state (EoS) and the collision term (including the Pauli-blocking and the medium-modified nucleon-nucleon elastic cross section (NNECS)). The momentum modifications of both, the mean-field potentials and the density dependent NNECS, are found to be sensitive to the collectivity of heavy-ion collisions. At INDRA energies ($\le 150$~MeV/nucleon), the dynamic transport with a soft EoS with momentum dependence and with the momentum-modified density-dependent NNECS describes the directed flow exhibited by hydrogen isotopes ($Z=1$) emitted at mid-rapidity fairly well.

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Qingfeng Li, Caiwan Shen, Chenchen Guo, Yongjia Wang, Zhuxia Li, J. Lukasik, W. Trautmann. 2011-01-29. Non-equilibrium dynamics in heavy ion collisions at low SIS energies. https://arxiv.org/abs/1101.5661

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