Central charged-particle multiplicities in pp interactions with |$eta$| < 0.8 and pt > 0.5 and 1 GeV measured with the ATLAS detector at the LHC

This note presents the results of the analysis of charged-particle spectra from proton-proton collisions at $\sqrt{s}$ = 0.9 TeV and 7 TeV in a restricted phase-space with respect to the nominal analysis [1] in order be able to directly compare the measurements with the results from other LHC experiments. The analysis highlights charged-particle distributions in minimum bias events as function of the transverse momentum of the particle pt, pseudorapidity $\eta$, particle multiplicity nch and the average transverse momentum pt as a function of nch. The measured distributions are corrected back to the hadron level, considering in the correction procedure inefficiencies of the trigger, vertex and track reconstruction. Two kinematical ranges are analysed on which ATLAS, CMS and ALICE agreed, defined by requiring at least one charged particle with |$eta$| < 0.8 and a minimum pT of 500 MeV or 1 GeV, respectively. Data taken at both energies ps = 0.9 TeV and ps = 7 TeV are analysed with these requirements and compared to predictions from Monte Carlo generators.