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arXiv · 1604.07230

Non-Gaussian eccentricity fluctuations

Hanna Grönqvist·Jean-Paul Blaizot·Jean-Yves Ollitrault
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Abstract

We study the fluctuations of the anisotropy of the energy density profile created in a high-energy collision at the LHC. We show that the anisotropy in harmonic $n$ has generic non-Gaussian fluctuations. We argue that these non-Gaussianities have a universal character for small systems such as p+Pb collisions, but not for large systems such as Pb+Pb collisions where they depend on the underlying non-Gaussian statistics of the initial density profile. We generalize expressions for the eccentricity cumulants $\varepsilon_2\{4\}$ and $\varepsilon_3\{4\}$ previously obtained within the independent-source model to a general fluctuating initial density profile.

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Hanna Grönqvist, Jean-Paul Blaizot, Jean-Yves Ollitrault. 2016-09-14. Non-Gaussian eccentricity fluctuations. https://doi.org/10.1103/physrevc.94.034905

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