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arXiv · 0711.0961

Perturbative QCD Calculations of Elliptic Flow and Shear Viscosity in Au+Au Collisions at $\sqrt{s_{NN}}=200$ GeV

Zhe Xu·Carsten Greiner·Horst Stoecker
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Abstract

The elliptic flow $v_2$ and the ratio of the shear viscosity over the entropy density, $η/s$, of gluon matter are calculated from the perturbative QCD (pQCD) based parton cascade Boltzmann approach of multiparton scatterings. For Au+Au collisions at $\sqrt{s}=200$A GeV the gluon plasma generates large $v_2$ values measured at the BNL Relativistic Heavy Ion Collider. Standard pQCD yields $η/s\approx 0.08-0.15$ as small as the lower bound found from the anti-de Sitter/conformal field theory conjecture.

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Zhe Xu, Carsten Greiner, Horst Stoecker. 2008-10-22. Perturbative QCD Calculations of Elliptic Flow and Shear Viscosity in Au+Au Collisions at $\sqrt{s_{NN}}=200$ GeV. https://doi.org/10.1103/physrevlett.101.082302

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