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arXiv · 1706.03666

Investigating the collision energy dependence of $η$/s in RHIC beam energy scan using Bayesian statistics

Jussi Auvinen·Iurii Karpenko·Jonah E. Bernhard·Steffen A. Bass
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Abstract

We determine the probability distributions of shear viscosity over the entropy density ratio $η/s$ in Au+Au collisions at $\sqrt{s_{NN}}=19.6, 39$, and $62.4$ GeV, using Bayesian inference and Gaussian process emulators for a model-to-data statistical analysis that probes the full input parameter space of a transport+viscous hydrodynamics hybrid model. We find the most likely value of $η/s$ to be larger at smaller $\sqrt{s_{NN}}$, although the uncertainties still allow for a constant value between 0.10 and 0.15 for the investigated collision energy range.

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Jussi Auvinen, Iurii Karpenko, Jonah E. Bernhard, Steffen A. Bass. 2017-06-12. Investigating the collision energy dependence of $η$/s in RHIC beam energy scan using Bayesian statistics. https://doi.org/10.1103/physrevc.97.044905

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