Prompt charm production in pp collisions at root s=7 TeV
Charm production at the LHC in pp collisions at root s = 7 TeV is studied with the LHCb detector. The decays D-0 -> K-pi(+), D+ -> K-pi(+)pi(+), D*(+) -> D-0(K-pi(+))pi(+), D-s(+) -> phi(K-K+)pi(+), Lambda(+)(c) -> pK(-)pi(+), and their charge conjugates are analysed in a data set corresponding to an integrated luminosity of 15 nb(-1). Differential cross-sections d sigma/dp(T) are measured for prompt production of the five charmed hadron species in bins of transverse momentum and rapidity in the region 0 < p(T) < 8 GeV/c and 2.0 < y < 4.5. Theoretical predictions are compared to the measured differential cross-sections. The integrated cross-sections of the charm hadrons are computed in the above p(T)-y range, and their ratios are reported. A combination of the five integrated cross-section measurements gives sigma(c (c) over bar)(pT<8 GeV/c, 2.0<y<4.5) = 1419 +/- 12 (stat) +/- 116 (syst) +/- 65 (frag) mu b. where the uncertainties are statistical, systematic, and due to the fragmentation functions. (C) 2013 CERN. Published by Elsevier B.V. All rights reserved.