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arXiv · 1210.6010

Extracting the shear viscosity of the quark-gluon plasma from flow in ultra-central heavy-ion collisions

Matthew Luzum·Jean-Yves Ollitrault
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Abstract

We propose a method for extracting the shear viscosity over entropy density ratio (eta/s) of the quark-gluon plasma from experimental data. We argue that uncertainty due to poor knowledge of the earliest stages of a heavy-ion collision is smallest for ultra-central events. The most precise value of eta/s can thus be obtained from a global fit to p_T-integrated Fourier harmonics of azimuthal correlations. We further outline a method for quantifying the overall uncertainty in the extracted value. Only after a comprehensive and systematic accounting of all sources of uncertainty can a reliable measurement be claimed. In these proceedings we report preliminary results; full and final results will be presented in a separate publication.

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Matthew Luzum, Jean-Yves Ollitrault. 2012-10-22. Extracting the shear viscosity of the quark-gluon plasma from flow in ultra-central heavy-ion collisions. https://doi.org/10.1016/j.nuclphysa.2013.02.028

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