Measurement of Event Plane Correlations in Pb-Pb Collisions at sNN=2.76TeV with the ATLAS Detector

A measurement of correlations between event-plane angles _Φn is presented as a function of centrality for Pb-Pb collisions ant sNN=2.76TeV. These correlations are estimated from observed event-plane angles _Χn obtained from charged particle or transverse energy flow measured over a large pseudorapidity range |η| < 4.8, followed by a resolution correction that accounts for the dispersion of _Χn relative to _Φn. Various correlators involving two or three event planes with acceptable resolution are measured. Significant positive correlations are observed for 4(_Φ2 - _Φ4), 6(_Φ2 - _Φ6), 6(_Φ3 - _Φ6), 2_Φ2 + 3_Φ3 - 5_Φ5, 2_Φ2 + 4_Φ4 - 6_Φ6 and -10_Φ2 + 4_Φ4 + 6_Φ6. However, the measured correlations for 2_Φ2 + 6_Φ3 + 4_Φ4 are negative. These results may shed light on the patterns of the fluctuation of the created matter in the initial state as well as the subsequent hydrodynamic evolution.