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

The production cross sections for prompt charmed mesons D-0, D+, D*(+) and D-s(+) were measured at mid-rapidity in proton-proton collisions at a centre-of-mass energy root s = 7 TeV with the ALICE detector at the Large Hadron Collider (LHC). D mesons were reconstructed from their decays D-0 -> K-pi(+), D+ -> K- pi(+)pi(+), D*(+) -> D-0 pi(+), D-s(+) -> phi pi(+) -> K-K+pi(+), 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 (c) over bar production cross section is likewise improved. The measured p(T)-differential cross sections are compared with the results of three perturbative QCD calculations.