Transverse-momentum and pseudorapidity distributions of charged hadrons in pp collisions at square root of s = 7 TeV.

Charged-hadron transverse-momentum and pseudorapidity distributions in proton-proton collisions at square root of s = 7  TeV are measured with the inner tracking system of the CMS detector at the LHC. The charged-hadron yield is obtained by counting the number of reconstructed hits, hit pairs, and f...

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Bibliographic Details
Main Authors: Khachatryan, V, Sirunyan, A, Tumasyan, A, Adam, W, Bergauer, T, Dragicevic, M, Erö, J, Fabjan, C, Friedl, M, Frühwirth, R, Ghete, V, Hammer, J, Hänsel, S, Hoch, M, Hörmann, N, Hrubec, J, Jeitler, M, Kasieczka, G, Kiesenhofer, W, Krammer, M, Liko, D, Mikulec, I, Pernicka, M, Rohringer, H, Schöfbeck, R
Format: Journal article
Language:English
Published: 2010
Description
Summary:Charged-hadron transverse-momentum and pseudorapidity distributions in proton-proton collisions at square root of s = 7  TeV are measured with the inner tracking system of the CMS detector at the LHC. The charged-hadron yield is obtained by counting the number of reconstructed hits, hit pairs, and fully reconstructed charged-particle tracks. The combination of the three methods gives a charged-particle multiplicity per unit of pseudorapidity dN(ch)/dη|(|η|<0.5) = 5.78 ± 0.01(stat) ± 0.23(syst) for non-single-diffractive events, higher than predicted by commonly used models. The relative increase in charged-particle multiplicity from square root of s = 0.9 to 7 TeV is [66.1 ± 1.0(stat) ± 4.2(syst)]%. The mean transverse momentum is measured to be 0.545 ± 0.005(stat) ± 0.015(syst)  GeV/c. The results are compared with similar measurements at lower energies.