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arXiv · 0706.1522

Viscosity Information from Relativistic Nuclear Collisions: How Perfect is the Fluid Observed at RHIC?

Paul Romatschke·Ulrike Romatschke
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Abstract

Relativistic viscous hydrodynamic fits to RHIC data on the centrality dependence of multiplicity, transverse and elliptic flow for sqrt{s}=200 GeV Au+Au collisions are presented. For Glauber-type initial conditions, while data on integrated v_2 is consistent with a ratio of viscosity over entropy density up to eta/s=0.16, data on minimum bias v_2 seems to favor a much smaller viscosity over entropy ratio, below the bound from the AdS/CFT conjecture. Some caveats on this result are discussed.

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Paul Romatschke, Ulrike Romatschke. 2007-10-26. Viscosity Information from Relativistic Nuclear Collisions: How Perfect is the Fluid Observed at RHIC?. https://doi.org/10.1103/physrevlett.99.172301

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