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

The production cross sections for prompt charmed mesons D0 , D+ , D∗+ and Ds+ were measured at mid-rapidity in proton–proton collisions at a centre-of-mass energy s=7TeV 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+ , Ds+→ϕπ+→K-K+π+ , and their charge conjugates.With respect to previous measurements in the same rapidity region, the coverage in transverse momentum ( pT ) is extended and the uncertainties are reduced by a factor of about two. The accuracy on the estimated total cc¯ production cross section is likewise improved. The measured pT -differential cross sections are compared with the results of three perturbative QCD calculations.