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arXiv · 1608.01823

Skewness of elliptic flow fluctuations

Giuliano Giacalone·Li Yan·Jacquelyn Noronha-Hostler·Jean-Yves Ollitrault
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Abstract

Using event-by-event hydrodynamic calculations, we find that the fluctuations of the elliptic flow ($v_2$) in the reaction plane have a negative skew. We compare the skewness of $v_2$ fluctuations to that of initial eccentricity fluctuations. We show that skewness is the main effect lifting the degeneracy between higher-order cumulants, with negative skew corresponding to the hierarchy $v_2\{4\}>v_2\{6\}$ observed in Pb+Pb collisions at the LHC. We describe how the skewness can be measured experimentally and show that hydrodynamics naturally reproduces its magnitude and centrality dependence.

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Giuliano Giacalone, Li Yan, Jacquelyn Noronha-Hostler, Jean-Yves Ollitrault. 2017-01-30. Skewness of elliptic flow fluctuations. https://doi.org/10.1103/physrevc.95.014913

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