CMS-QCD-10-006

CMS-QCD-10-006 ; CERN-PH-EP-2010-009
Transverse-momentum and pseudorapidity distributions of charged hadrons in pp collisions at $\sqrt{s}$ = 7 TeV
CMS Collaboration
19 May 2010
Phys. Rev. Lett. 105 (2010) 022002
Abstract: Charged-hadron transverse-momentum and pseudorapidity distributions in proton-proton collisions at $\sqrt{s} =$ 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 ${ \mathrm{d} N_{\text{ch}} / \mathrn{d} \eta} \|_{\|\eta\| < 0.5} = 5.78\pm 0.01\stat\pm 0.23\syst$ for non-single-diffractive events, higher than predicted by commonly used models. The relative increase in charged-particle multiplicity from $\sqrt{s} =$ 0.9 to 7 TeV is 66.1% $\pm$ 1.0% (stat) $\pm$ 4.2% (syst). The mean transverse momentum is measured to be 0.545 $\pm$ 0.005 (stat) $\pm$ 0.015 (syst) GeV/ $c$ . The results are compared with similar measurements at lower energies.
Links: e-print arXiv:1005.3299 [hep-ex] (PDF) ; CDS record ; inSPIRE record ; Public twiki page ; HepData record ; CADI line (restricted) ;

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