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arXiv · 1904.10350

Primordial non-Gaussianity in heavy-ion collisions

Rajeev S. Bhalerao·Giuliano Giacalone·Jean-Yves Ollitrault
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Abstract

We show that experimental data on cumulants of anisotropic flow in heavy-ion collisions probe the non-Gaussian statistics of the energy density field created right after the collision. We carry out a perturbative expansion of the initial anisotropies of the system in terms of its density fluctuations. We argue that the correlation between the magnitudes of elliptic flow and triangular flow, dubbed $sc(3,2)$, is generically of the same sign and order of magnitude as the kurtosis of triangular flow in a hydrodynamic picture. The experimental observation that these quantities are negative implies that the distribution of energy around a given point has positive skew.

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Rajeev S. Bhalerao, Giuliano Giacalone, Jean-Yves Ollitrault. 2019-08-06. Primordial non-Gaussianity in heavy-ion collisions. https://doi.org/10.1103/physrevc.100.014909

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