Skewness of elliptic flow fluctuations
Giuliano Giacalone🇫🇷 · Li Yan🇫🇷 · Jacquelyn Noronha-Hostler🇺🇸 · Jean-Yves Ollitrault🇫🇷
Using event-by-event hydrodynamic calculations, we find that the fluctuations of the elliptic flow () in the reaction plane have a negative skew. We compare the skewness of 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 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.