Measurements of Elliptic Flow with the ATLAS Detector

The measurement of the azimuthal anisotropy of charged particles obtained with the multi-particle correlations method is presented and compared to the results obtained with the event plane method for Pb + Pb collisions at 2.76 TeV from the ATLAS experiment. Results on flow harmonics, determined from the cumulants of particle correlations, over wide transverse momenta (0.5<pT<20GeV), pseudorapidity (|η|<2.5) and centrality ranges are shown. The applied cumulant approach provides a unique handle on non-flow effects and allows for the evaluation of the genuine flow fluctuations. Derived estimates of the non-flow correlations and the magnitude of flow fluctuations are discussed. Centrality and pseudorapidity dependence of the elliptic flow measured with the event-plane method and integrated down to very low pT is also shown and compared to the results obtained by the other LHC experiments