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arXiv · 0910.1400

Energy Dependence of Directed Flow in Au+Au Collisions from a Multi-phase Transport Model

J. Y. Chen·J. X. Zuo·X. Z. Cai·F. Liu·Y. G. Ma·A. H. Tang
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Abstract

The directed flow of charged hadron and identified particles has been studied in the framework of a multi-phase transport (AMPT) model, for $^{197}$Au+$^{197}$Au collisions at $\sqrt{s_{NN}}=$200, 130, 62.4, 39, 17.2 and 9.2 GeV. The rapidity, centrality and energy dependence of directed flow for charged particles over a wide rapidity range are presented. AMPT model gives the correct $v_1(y)$ slope, as well as its trend as a function of energy, while it underestimates the magnitude. Within the AMPT model, the proton $v_1$ slope is found to change its sign when the energy increases to 130 GeV - a feature that is consistent with ``anti-flow''. Hadronic re-scattering is found having little effect on $v_1$ at top RHIC energies. These studies can help us to understand the collective dynamics at early times in relativistic heavy-ion collisions, and they can also be served as references for the RHIC Beam Energy Scan program.

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J. Y. Chen, J. X. Zuo, X. Z. Cai, F. Liu, Y. G. Ma, A. H. Tang. 2009-12-09. Energy Dependence of Directed Flow in Au+Au Collisions from a Multi-phase Transport Model. https://doi.org/10.1103/physrevc.81.014904

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