Studies of higher-order flow harmonics in PbPb collisions at 2.76 TeV with CMS

High-order Fourier harmonics ($v_n$, $n > 2$) in the azimuthal distributions of charged particles produced in PbPb collisions at a nucleon-nucleon centre-of-mass energy $\sqrt{s_{_{NN}}}$ = 2.76 TeV are presented. The $v_n$ coefficients are studied using the event-plane method and a Fourier decomposition analysis of the two particle correlations in various collision centrality, $p_{T}$ and $\eta$ ranges. A unique measurement of $v_n$ in the ultra-central collisions (UCC) is performed using the long-range component of the two particle correlations. These data provide strong constraints on the theoretical models of the initial condition in heavy ion collisions and the transport properties of the produced medium.