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arXiv · 1512.01538

Moving forward to constrain the shear viscosity of QCD matter

Gabriel Denicol·Akihiko Monnai·Bjoern Schenke
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Abstract

We demonstrate that measurements of rapidity differential anisotropic flow in heavy ion collisions can constrain the temperature dependence of the shear viscosity to entropy density ratio η/s of QCD matter. Comparing results from hydrodynamic calculations with experimental data from RHIC, we find evidence for a small η/s $\approx$ 0.04 in the QCD cross-over region and a strong temperature dependence in the hadronic phase. A temperature independent η/s is disfavored by the data. We further show that measurements of the event-by-event flow as a function of rapidity can be used to independently constrain the initial state fluctuations in three dimensions and the temperature dependent transport properties of QCD matter.

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Gabriel Denicol, Akihiko Monnai, Bjoern Schenke. 2015-12-04. Moving forward to constrain the shear viscosity of QCD matter. https://doi.org/10.1103/physrevlett.116.212301

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