Charm production at the LHC in pp collisions at sqrt(s)=7 TeV is studied with the LHCb detector. The decays D0 -> K- pi+, D+ -> K- pi+ pi+, D*+ -> D0(K- pi+) pi+, D_s+ -> phi(K- K+) pi+, Lambda_c+ -> p K- pi+, and their charge conjugates are analysed in a data set corresponding to an integrated luminosity of 15 nb^{-1}. Differential cross-sections dsigma/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\bar{c})_{p_T < 8 GeV/c, 2.0 < y < 4.5} = 1419 +/- 12 (stat) +/- 116 (syst) +/- 65 (frag) microbarn, where the uncertainties are statistical, systematic, and due to the fragmentation functions.
The differential cross-section for the inclusive production of $\psi(2S)$ mesons in $pp$ collisions at $\sqrt{s}$ =7 TeV has been measured with the LHCb detector. The data sample corresponds to an integrated luminosity of 36 pb$^{-1}$ collected during 2010. The $\psi(2S)$ mesons are reconstructed in the decay channels $\psi(2S) \rightarrow \mu^{+} \mu^{-}$ and $\psi(2S)$ $\rightarrow$ $J$/$\psi \pi^{+}\pi^{-}$, with the $J$/$\psi$ meson decaying into two muons. Results are presented both for promptly produced $\psi(2S)$ mesons and for those originating from $b$-hadron decays. In the kinematic range $p_{\rm T}(\psi(2S))$ $\leq$ 16 GeV/$c$ and 2 < $y$($\psi(2S))$ $\leq$ 4.5 we measure \begin{eqnarray*} \sigma_{\rm prompt}(\psi(2S)) &=& 1.44 \pm 0.01~(\text{stat})\pm 0.12~(\text{syst})^{+0.20}_{-0.40}~(\text{pol})~{\rm \mu b}, \\ \sigma_{b}(\psi(2S)) &=& 0.25 \pm 0.01~(\text{stat}) \pm 0.02~(\text{syst})~{\rm \mu b}, \end{eqnarray*} where the last uncertainty on the prompt cross-section is due to the unknown $\psi(2S)$ polarization. Recent QCD calculations are found to be in good agreement with our measurements. Combining the present result with the LHCb $J$/$\psi$ measurements we determine the inclusive branching fraction \begin{equation*} \mathcal{B}(b \rightarrow \psi(2S) X) = (2.73 \pm 0.06~(\text{stat}) \pm 0.16~(\text{syst}) \pm 0.24~(\text{BF})) \times 10^{-3}, \end{equation*} where the last uncertainty is due to the $\mathcal{B}(b \rightarrow J/\psi X)$, $\mathcal{B}(J/\psi \rightarrow \mu^+ \mu^-)$ and $\mathcal{B}(\psi(2S) \rightarrow e^+ e^-)$ branching fraction uncertainties. All above results are corrected by an erratum included as an appendix.
The cross-section for inclusive phi meson production in pp collisions at a centre-of-mass energy of sqrt(s) = 7 TeV has been measured with the LHCb detector at the Large Hadron Collider. The differential cross-section is measured as a function of the phi transverse momentum p_T and rapidity y in the region 0.6 < p_T < 5.0 GeV/c and 2.44 < y < 4.06. The cross-section for inclusive phi production in this kinematic range is sigma(pp -> phi X) = 1758 pm 19(stat) ^{+43}_{-14}(syst) pm 182(scale) microbarn, where the first systematic uncertainty depends on the p_T and y region and the second is related to the overall scale. Predictions based on the Pythia 6.4 generator underestimate the cross-section.
The production of B+- mesons in proton-proton collisions at sqrt(s)=7 TeV is studied using 35 pb-1 of data collected by the LHCb detector. The B+- mesons are reconstructed exclusively in the B+- -> J/psi K+- mode, with J/psi -> mu+ mu-. The differential production cross-section is measured as a function of the B+- transverse momentum in the fiducial region 0 < pT < 40 GeV/c and with rapidity 2.0 < y < 4.5. The total cross-section, summing up B+ and B-, is measured to be sigma(pp -> B+- X, 0 < pT < 40 GeV/c, 2.0 < y < 4.5) = 41.4 +- 1.5 (stat.) +- 3.1 (syst.) mub.
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