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arXiv · 1001.2736

Does the NJL chiral phase transition affect the elliptic flow of a fluid at fixed $η/s$?

S. Plumari·V. Baran·M. Di Toro·G. Ferini·V. Greco
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Abstract

We have derived and solved numerically the Boltzmann-Vlasov transport equations that includes both two-body collisions and the chiral phase transition by mean of NJL-field dynamics. The scope is to understand if the field dynamics supply new genuine effects on the build-up of the elliptic flow $v_2$, a measure of the asymmetry in the momentum space, and in particular if it can affect the relation between $v_2$ and the shear viscosity to entropy ratio $η/s$. Solving the transport equation with a constant cross section for the condition of $Au+Au$ collisions at $\sqrt{s_{NN}}=200$ AGeV it is shown a sizable suppression of $v_2$ due to the attractive nature of the field dynamics that generates the constituent mass. However the key result is that if $η/s$ of the system is kept fixed by an appropriate local renormalization of the cross section the $v_2$ does not depend on the details of the collisional and/or field dynamics and in particular it is not affected significantly by the chiral phase transition.

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S. Plumari, V. Baran, M. Di Toro, G. Ferini, V. Greco. 2010-01-15. Does the NJL chiral phase transition affect the elliptic flow of a fluid at fixed $η/s$?. https://doi.org/10.1016/j.physletb.2010.04.034

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