Charged particle multiplicity in Pb+Pb collisions at sqrt{s}=2.76 TeV by ATLAS expriment

We present the study of charged particle pseudorapidity density distribution over a broad range of pseudorapidity and centrality in Pb+Pb collisions at $sqrt{s_{NN}} = 2.76$~TeV with ATLAS detector at LHC. The global shapes of multiplicity density distributions over four units of pseudorapidity from -2 to 2 are presented. The dependence of mid-rapidity density scaled by per participating nucleon pair ($dN_{ch}/deta(|eta|<0.5)/(0.5N_{part})$) on centrality and the number of participants ($N_{part}$) is presented and used with results of previous measurements to evaluate the collision energy dependence ($sqrt{s_{NN}}$).