Primordial non-Gaussianity in heavy-ion collisions

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.

11 pages, 4 figures; v2: minor revisions

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Cited by in corpus (8)

• Theoretical and Experimental Constraints for the Equation of State of Dense and Hot Matter
• Higher order Symmetric Cumulants
• Skewness of mean transverse momentum fluctuations in heavy-ion collisions
• Predictions for the sPHENIX physics program
• Collectivity in large and small systems formed in ultrarelativistic collisions
• Model comparison for initial density fluctuations in high energy heavy ion collisions
• Rapidity dependence of mean transverse momentum fluctuation and decorrelation in baryon-dense medium
• Effect of transverse momentum conservation and flow on symmetric cumulants $s{c}_{2,3}\left\{4\right\}$ and $s{c}_{2,3,4}\left\{6\right\}$