TY - JOUR AU - ATLAS Collaboration (Aad, G. et al AU - Amoros, G. AU - Cabrera Urban, S. AU - Castillo Gimenez, V. AU - Costa, M. J. AU - Escobar, C. AU - Ferrer, A. AU - Fiorini, L. AU - Fuster, J. AU - Garcia, C. AU - Gonzalez de la Hoz, S. AU - Hernandez Jimenez, Y. AU - Higon-Rodriguez, E. AU - Irles Quiles, A. AU - Kaci, M. AU - Lacasta, C. AU - Lacuesta, V. R. AU - Marti-Garcia, S. AU - Miñano, M. AU - Mitsou, V. A. AU - Moles-Valls, R. AU - Moreno Llacer, M. AU - Oliver Garcia, E. AU - Perez Garcia-Estañ, M. T. AU - Ros, E. AU - Salt, J. AU - Solans, C. A. AU - Soldevila, U. AU - Sanchez, J. AU - Torro Pastor, E. AU - Valladolid Gallego, E. AU - Valls Ferrer, J. A. AU - Villaplana Perez, M. AU - Vos, M. AU - Wildauer, A. PY - 2012 DA - 2012// TI - 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 T2 - Phys. Lett. B JO - Physics Letters B SP - 363 EP - 382 VL - 710 IS - 3 PB - Elsevier Science Bv AB - 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. SN - 0370-2693 UR - http://arxiv.org/abs/1108.6027 UR - https://doi.org/10.1016/j.physletb.2012.02.045 DO - 10.1016/j.physletb.2012.02.045 LA - English N1 - WOS:000303081900001 ID - ATLASCollaborationAad_etal2012 ER -