Flow and Correlations in Pb–Pb Collisions at sNN=2.76 TeV with the ATLAS Detector at the LHC

Abstract

Abstract Recent measurements from the ATLAS experiment of the azimuthal anisotropy of charged hadron production in the relativistic Pb–Pb collisions at the Large Hadron Collider (LHC) are presented. The results on the integrated and differential flow harmonics were obtained using a variety of approaches, e.g. the event plane, two-particle correlations, two- and four-particle cumulant methods, over a wide range of centrality (0–80)%, pseudorapidity ( | η | 2.5 ) and transverse momentum of 0.03–20 GeV and 45–210 GeV for charged particles and jets respectively. These detailed measurements at low- and high- p T provide new insights into the hydrodynamic picture of the Quark–Gluon Plasma and probe the path-length dependence of partonic energy loss in the dense medium. Fluctuations in the geometry of the initial interaction region are studied by the measurement of event-by-event v 2 – v 4 harmonics, as well as by flow harmonics from the cumulant method. Additional information on initial geometry fluctuations is provided by measurement of the dipolar flow ( v 1 ) , as well as by the correlations of two and three reaction plane angles of different orders harmonics.