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arXiv · 1603.09087

An explanation of the elliptic flow difference between proton and anti-proton from the UrQMD model with hadron potentials

Qingfeng Li·Yongjia Wang·Xiaobao Wang·Caiwan Shen
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Abstract

The time evolution of both proton and anti-proton $v_2$ flows from Au+Au collisions at $\sqrt{s_{NN}}$=7.7 GeV are examined by using both pure cascade and mean-field potential versions of the UrQMD model. Due to a stronger repulsion at the early stage introduced by the repulsive potentials and hence much less annihilation probabilities, anti-protons are frozen out earlier with smaller $v_2$ values. Therefore, the experimental data of anti-proton $v_2$ as well as the flow difference between proton and anti-proton can be reasonably described with the potential version of UrQMD.

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Qingfeng Li, Yongjia Wang, Xiaobao Wang, Caiwan Shen. 2016-03-30. An explanation of the elliptic flow difference between proton and anti-proton from the UrQMD model with hadron potentials. https://doi.org/10.1007/s11433-015-5774-4

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