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Has the QCD Critical Point been Signaled by Observations at RHIC ?

Roy A. Lacey·N. N. Ajitanand·J. M. Alexander·P. Chung·W. G. Holzmann·M. Issah·A. Taranenko·P. Danielewicz·Horst Stocker
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Abstract

The shear viscosity to entropy ratio ($η/s$) is estimated for the hot and dense QCD matter created in Au+Au collisions at RHIC ($\sqrt{s_{NN}}=200$ GeV). A very low value is found $η/s \sim 0.1$, which is close to the conjectured lower bound ($1/4π$). It is argued that such a low value is indicative of thermodynamic trajectories for the decaying matter which lie close to the QCD critical end point.

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Roy A. Lacey, N. N. Ajitanand, J. M. Alexander, P. Chung, W. G. Holzmann, M. Issah, A. Taranenko, P. Danielewicz, Horst Stocker. 2007-02-14. Has the QCD Critical Point been Signaled by Observations at RHIC ?. https://doi.org/10.1103/physrevlett.98.092301

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