TY - JOUR AU - ATLAS Collaboration (Aad, G. et al AU - Cabrera Urban, S. AU - Castillo Gimenez, V. AU - Costa, M. J. AU - Fassi, F. AU - Ferrer, A. AU - Fiorini, L. AU - Fuster, J. AU - Garcia, C. AU - Garcia Navarro, J. E. AU - Gonzalez de la Hoz, S. AU - Hernandez Jimenez, Y. AU - Higon-Rodriguez, E. AU - Irles Quiles, A. AU - Kaci, M. AU - Lacasta, C. AU - Lacuesta, V. R. AU - March, L. AU - Marti-Garcia, S. AU - Miñano, M. AU - Mitsou, V. A. AU - Moles-Valls, R. AU - Moreno Llacer, M. AU - Oliver Garcia, E. AU - Pedraza Lopez, S. AU - Perez Garcia-Estañ, M. T. AU - Romero Adam, E. AU - Ros, E. AU - Salt, J. AU - Sanchez Martinez, V. AU - Soldevila, U. AU - Sanchez, J. AU - Torro Pastor, E. AU - Valero, A. AU - Valladolid Gallego, E. AU - Valls Ferrer, J. A. AU - Villaplana Perez, M. AU - Vos, M. PY - 2013 DA - 2013// TI - Measurement of the distributions of event-by-event flow harmonics in lead-lead collisions at root s(NN)=2.76 TeV with the ATLAS detector at the LHC T2 - J. High Energy Phys. JO - Journal of High Energy Physics SP - 183 EP - 57pp VL - 11 IS - 11 PB - Springer KW - Heavy-ion collision KW - harmonic flow KW - event-by-event fluctuation KW - unfolding KW - Hadron-Hadron Scattering AB - The distributions of event-by-event harmonic flow coefficients v (n) for n = 2- 4 are measured in = 2.76 TeV Pb + Pb collisions using the ATLAS detector at the LHC. The measurements are performed using charged particles with transverse momentum p (T) > 0.5 GeV and in the pseudorapidity range |eta| < 2.5 in a dataset of approximately 7 μb(-1) recorded in 2010. The shapes of the v (n) distributions suggest that the associated flow vectors are described by a two-dimensional Gaussian function in central collisions for v (2) and over most of the measured centrality range for v (3) and v (4). Significant deviations from this function are observed for v (2) in mid-central and peripheral collisions, and a small deviation is observed for v (3) in mid-central collisions. In order to be sensitive to these deviations, it is shown that the commonly used multi-particle cumulants, involving four particles or more, need to be measured with a precision better than a few percent. The v (n) distributions are also measured independently for charged particles with 0.5 < p (T) < 1 GeV and p (T) > 1 GeV. When these distributions are rescaled to the same mean values, the adjusted shapes are found to be nearly the same for these two p (T) ranges. The v (n) distributions are compared with the eccentricity distributions from two models for the initial collision geometry: a Glauber model and a model that includes corrections to the initial geometry due to gluon saturation effects. Both models fail to describe the experimental data consistently over most of the measured centrality range. SN - 1029-8479 UR - http://arxiv.org/abs/arXiv:1305.2942 UR - https://doi.org/10.1007/JHEP11(2013)183 DO - 10.1007/JHEP11(2013)183 LA - English N1 - WOS:000328332400001 ID - ATLASCollaborationAad_etal2013 ER -