English

Skewness of elliptic flow fluctuations

Nuclear Theory 2017-01-31 v3 High Energy Physics - Phenomenology Nuclear Experiment

Abstract

Using event-by-event hydrodynamic calculations, we find that the fluctuations of the elliptic flow (v2v_2) in the reaction plane have a negative skew. We compare the skewness of v2v_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 v2{4}>v2{6}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.

Keywords

Cite

@article{arxiv.1608.01823,
  title  = {Skewness of elliptic flow fluctuations},
  author = {Giuliano Giacalone and Li Yan and Jacquelyn Noronha-Hostler and Jean-Yves Ollitrault},
  journal= {arXiv preprint arXiv:1608.01823},
  year   = {2017}
}

Comments

7 pages, 6 figures. v2: We now use data from Fig.9b of arXiv:1408.4342 instead of using data from Fig.9a. v3: Published version. Overall revision of the text. Added discussion after Figure 6. Statistics of events is increased in central collisions