RESULTS ON ELLIPTIC FLOW AND HIGHER-ORDER FLOW HARMONICS IN Pb + Pb COLLISIONS FROM THE ATLAS DETECTOR AT THE LHC

摘要

The measurement of elliptic flow and higher-order flow harmonics of charged particles in s_(NN)~(1/2) = 2.76 TeV Pb + Pb collisions with the ATLAS detector is presented. Fourier harmonics v_2-v_6 were extracted with the event plane and two-particle correlation methods in a broad range of transverse momentum (0.5 GeV < p_T < 20 GeV), pseudorapidity (|η| < 2.5) and collision centrality (0-80%). Results obtained with the two methods were found to be consistent. Elliptic flow shows rapid rise with p_T up to about 3 GeV followed by a decrease within range 3-8 GeV and then becomes weakly dependent at the highest p_T. Similar trend is observed for higher-order harmonics. As a function of pseudorapidity a very weak dependence of all flow harmonics is measured.