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arXiv · 1310.1764

Evolution of elliptic and triangular flow as a function of collision energy in a hybrid model

Jussi Auvinen·Hannah Petersen
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Abstract

We study the collision energy dependence of elliptic flow v_2 and triangular flow v_3 in Au+Au collisions within the energy range sqrt(s_{NN}) = 5-200 GeV, utilizing a transport + hydrodynamics hybrid model. The transport part is described by the Ultrarelativistic Quantum Molecular Dynamics (UrQMD) approach, combined with an intermediate (3+1)-dimensional ideal hydrodynamical evolution phase using a chiral model equation of state. We find the decrease of v_2 produced by hydrodynamics at lower collision energies partially compensated by the transport dynamics. This does not apply to v_3, which falls to 0 in midcentral collisions at sqrt(s_{NN}) = 5 GeV. We conclude that the triangular flow provides the clearer signal for the formation of low-viscous fluid in heavy ion collisions.

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Jussi Auvinen, Hannah Petersen. 2014-04-10. Evolution of elliptic and triangular flow as a function of collision energy in a hybrid model. https://doi.org/10.1103/physrevc.88.064908

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