Measurement of elliptic flow and higher-order flow harmonics from the event plane and two particle correlation methods in sqrt{s_{NN}) = 2.76 TeV Pb+Pb collisions with ATLAS detector at the LHC

The measurement of the elliptic flow for charged particles in Pb+Pb collisions at sqrt(s_NN)=2.76 TeV with the ATLAS detector will be presented in a wide range of pseudorapidity, transverse momentum and collision centrality. The elliptic flow is measured by correlating azimuthal angles of reconstructed particle tracks with the event plane angle obtained from forward calorimeters. A large pseudorapidity gap between the tracking system and forward calorimeters significantly reduces contributions from short-range non-flow effects. For the first time at this energy, elliptic flow is measured over 5 units of pseudorapidity, from -2.5 to 2.5, and over a broad range in transverse momentum, 0.5-20 GeV. We also present precision measurements for the first six flow harmonics ($v_1$-$v-6$) using both the event plane method as well as two-particle correlations, a broad $p_T$ range, and with fine centrality selections. The results will be discussed in the context of previous measurements and theoretical model predictions.