Measurement of D-meson production at mid-rapidity in pp collisions at √(s) = 7 TeV

The production cross sections for prompt charmed mesons D⁰, D⁺, D^*+ and D_s⁺ were measured at mid-rapidity in proton-proton collisions at a centre-of-mass energy √(s) = 7 TeV with the ALICE detector at the Large Hadron Collider (LHC). D mesons were reconstructed from their decays D⁰ → K^-π⁺, D⁺ → K^-π⁺π⁺, D^*+ → D⁰π⁺, D_s⁺ → φπ⁺ → K^-K⁺π⁺, and their charge conjugates. With respect to previous measurements in the same rapidity region, the coverage in transverse momentum (p_T) is extended and the uncertainties are reduced by a factor of about two. The accuracy on the estimated total c anti c production cross section is likewise improved. The measured p_T-differential cross sections are compared with the results of three perturbative QCD calculations. (orig.)