Measurement of D-meson production in pp collisions with ALICE at the LHC

The p$_\mathrm{T}$ -differential cross sectionCross section of D mesons in the rapidity range $|y|< 0.5$ was measured in pp collisions at $\sqrt{s} = 2.76$ , 7 and 8 TeV. D mesons were reconstructed in their hadronic decay channels by means of the invariant mass analysis. The D-meson production cross sectionsCross section are compared among different energies and to pQCD calculations. The prompt D mesons are also studied as a function of the multiplicity of charged particles produced in inelastic pp collisions at a centre-of-mass energy of $\sqrt{s} = 7$ TeV. The measurements are compared with model calculations.