Elliptic and higher order flow measured in a large phase space in $\sqrt{s_{NN}}$ = 2.76 TeV Lead-Lead Collisions

We present the measurements of flow harmonics $v_2$-$v_6$ using the Event Plane (EP) method and Two Particle Correlations (2PC) in broad $p_T$, $eta$ and centrality ranges using the ATLAS detector at LHC. ATLAS recorded, $9mu b^{-1}$ Pb+Pb data in the 2010 heavy ion run. This large dataset and large detector acceptance :$2pi$ in azimuth and $pm 2.5$ units in $eta$ for charged hadrons, allows for a detailed study of the flow harmonics. We show that the novel structures seen in two particle correlations such as the near and away side extit{ridge} as well as the so called `` extit{mach-cone}" are entirely accounted for by the collective flow. Some interesting scaling relations between the $v_n$ are also discussed.