%0 Journal Article %T Measurement of the centrality dependence of the charged particle pseudorapidity distribution in lead-lead collisions at root s(NN)=2.76 TeV with the ATLAS detector %A ATLAS Collaboration (Aad, G. et al %A Amoros, G. %A Cabrera Urban, S. %A Castillo Gimenez, V. %A Costa, M. J. %A Escobar, C. %A Ferrer, A. %A Fiorini, L. %A Fuster, J. %A Garcia, C. %A Gonzalez de la Hoz, S. %A Hernandez Jimenez, Y. %A Higon-Rodriguez, E. %A Irles Quiles, A. %A Kaci, M. %A Lacasta, C. %A Lacuesta, V. R. %A Marti-Garcia, S. %A Miñano, M. %A Mitsou, V. A. %A Moles-Valls, R. %A Moreno Llacer, M. %A Oliver Garcia, E. %A Perez Garcia-Estañ, M. T. %A Ros, E. %A Salt, J. %A Solans, C. A. %A Soldevila, U. %A Sanchez, J. %A Torro Pastor, E. %A Valladolid Gallego, E. %A Valls Ferrer, J. A. %A Villaplana Perez, M. %A Vos, M. %A Wildauer, A. %J Physics Letters B %D 2012 %V 710 %N 3 %I Elsevier Science Bv %@ 0370-2693 %G English %F ATLASCollaborationAad_etal2012 %O WOS:000303081900001 %O exported from refbase (https://references.ific.uv.es/refbase/show.php?record=1009), last updated on Thu, 01 Nov 2012 19:58:01 +0000 %X The ATLAS experiment at the LHC has measured the centrality dependence of charged particle pseudorapidity distributions over vertical bar eta vertical bar < 2 in lead-lead collisions at a nucleon-nucleon centre-of-mass energy of root s(NN) = 2.76 TeV. In order to include particles with transverse momentum as low as 30 MeV, the data were recorded with the central solenoid magnet off. Charged particles were reconstructed with two algorithms (2-point "tracklets" and full tracks) using information from the pixel detector only. The lead-lead collision centrality was characterized by the total transverse energy in the forward calorimeter in the range 3.2 < vertical bar eta vertical bar< 4.9. Measurements are presented of the per-event charged particle pseudorapidity distribution, dN(ch)/d eta, and the average charged particle multiplicity in the pseudorapidity interval vertical bar eta vertical bar < 0.5 in several intervals of collision centrality. The results are compared to previous mid-rapidity measurements at the LHC and RHIC. The variation of the mid-rapidity charged particle yield per colliding nucleon pair with the number of participants is consistent with lower root s(NN) results. The shape of the dN(ch)/d eta distribution is found to be independent of centrality within the systematic uncertainties of the measurement. %R 10.1016/j.physletb.2012.02.045 %U http://arxiv.org/abs/1108.6027 %U https://doi.org/10.1016/j.physletb.2012.02.045 %P 363-382