Measurements of D[superscript 0] and D[superscript *] production in p+p collisions at √s=200  GeV

08 Jan 2013

We report measurements of charmed-hadron (D[superscript 0],D[superscript *]) production cross sections at midrapidity in p+p collisions at a center-of-mass energy of 200 GeV by the STAR experiment. Charmed hadrons were reconstructed via the hadronic decays D[superscript 0]→K[superscript -]π[superscript +], D[superscript *+]→D[superscript 0]π+→K[superscript -]π[superscript +]π[superscript +] and their charge conjugates, covering the p[subscript T] range of 0.6–2.0 and 2.0–6.0  GeV/c for D[superscript 0] and D[superscript *+], respectively. From this analysis, the charm-pair production cross section at midrapidity is dσ/dy|[subscript y=0[superscript cc̅]] =170±45(stat)[subscript -59][superscript +38](sys)  μb. The extracted charm-pair cross section is compared to perturbative QCD calculations. The transverse momentum differential cross section is found to be consistent with the upper bound of a fixed-order next-to-leading logarithm calculation.