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Measurement of charm production at central rapidity in proton-proton collisions at sqrt(s) = 2.76 TeV

The pt-differential production cross sections of the prompt (B feed-down subtracted) charmed mesons D0, D+, and D+ in the rapidity range |y| < 0.5, and for transverse momentum 1 < pt < 12 GeV/c, were measured in proton-proton collisions at sqrt(s) = 2.76 TeV with the ALICE detector at the Large Hadron Collider. The analysis exploited the hadronic decays D0 -> K−π+, D+ -> K−π+π+, D+ -> D0π+, and their charge conjugates, and was performed on a Lint = 1.1 nb−1 event sample collected in 2011 with a minimum-bias trigger. The total charm production cross section at sqrt(s) = 2.76 TeV and at 7 TeV was evaluated by extrapolating to the full phase space the pt- differential production cross sections at sqrt(s) = 2.76 TeV and our previous measurements at sqrt(s) = 7 TeV. The results were compared to existing measurements and to perturbative-QCD calculations. The fraction of cbar-d D mesons produced in a vector state was also determined.

Hadron-Hadron scattering

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