Non-Gaussian elliptic-flow fluctuations in PbPb collisions at root S-NN=5.02 TeV


Sirunyan A. M. , Tumasyan A., Adam W., Ambrogi F., Asilar E., Bergauer T., ...More

PHYSICS LETTERS B, vol.789, pp.643-665, 2019 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 789
  • Publication Date: 2019
  • Doi Number: 10.1016/j.physletb.2018.11.063
  • Title of Journal : PHYSICS LETTERS B
  • Page Numbers: pp.643-665
  • Keywords: Event-by-event elliptic flow, Non-Gaussian flow fluctuations, Unfolding, QUARK-GLUON PLASMA, PARTICLE-PRODUCTION, NUCLEAR COLLISIONS, PERSPECTIVE, ANISOTROPY, VISCOSITY

Abstract

Event-by-event fluctuations in the elliptic-flow coefficient v(2) are studied in PbPb collisions at root S-NN = 5.02 TeV using the CMS detector at the CERN LHC. Elliptic-flow probability distributions p(v(2)) for charged particles with transverse momentum 0.3 < p(T) < 3.0 GeV/c and pseudorapidity vertical bar eta vertical bar < 1.0 are determined for different collision centrality classes. The moments of the p(v(2)) distributions are used to calculate the v(2) coefficients based on cumulant orders 2, 4, 6, and 8. A rank ordering of the higher-order cumulant results and nonzero standardized skewness values obtained for the p(v(2)) distributions indicate non-Gaussian initial-state fluctuations. Bessel-Gaussian and elliptic power fits to the flow distributions are studied to characterize the initial-state spatial anisotropy. (C) 2018 The Author(s). Published by Elsevier B.V.