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arXiv · 1611.08023

Equation of state dependence of directed flow in a microscopic transport model

Yasushi Nara·Harri Niemi·Jan Steinheimer·Horst Stoecker
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Abstract

We study the sensitivities of the directed flow in Au+Au collisions on the equation of state (EoS), employing the transport theoretical model JAM. The EoS is modified by introducing a new collision term in order to control the pressure of a system by appropriately selecting an azimuthal angle in two-body collisions according to a given EoS. It is shown that this approach is an efficient method to modify the EoS in a transport model. The beam energy dependence of the directed flow of protons is examined with two different EoS, a first-order phase transition and crossover. It is found that our approach yields quite similar results as hydrodynamical predictions on the beam energy dependence of the directed flow; Transport theory predicts a minimum in the excitation function of the slope of proton directed flow and does indeed yield negative directed flow, if the EoS with a first-order phase transition is employed. Our result strongly suggests that the highest sensitivity for the critical point can be seen in the beam energy range of $4.7\leq\srtNN\leq11.5$ GeV.

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Yasushi Nara, Harri Niemi, Jan Steinheimer, Horst Stoecker. 2016-11-23. Equation of state dependence of directed flow in a microscopic transport model. https://doi.org/10.1016/j.physletb.2017.02.020

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