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Measurement of ψ(2S) meson production in pp collisions at √ s = 7 TeV Abstract The differential cross-section for the inclusive production of ψ(2S) mesons in pp collisions at √ s = 7 TeV has been measured with the LHCb detector. The data sample corresponds to an integrated luminosity of 36 pb −1. The ψ(2S) mesons are reconstructed in the decay channels(More)
The calibration and performance of the opposite-side flavour tagging algorithms used for the measurements of time-dependent asymmetries at the LHCb experiment are described. The algorithms have been developed using simulated events and optimized and calibrated with B + → J /ψK + , B 0 → J /ψK * 0 and B 0 → D * − μ + ν μ decay modes with 0.37 fb −1 of data(More)
The production of Υ (1S), Υ (2S) and Υ (3S) mesons in proton-proton collisions at the centre-of-mass energy of √ s = 7 TeV is studied with the LHCb detector. The analysis is based on a data sample of 25 pb −1 collected at the Large Hadron Collider. The Υ mesons are reconstructed in the decay mode Υ → μ + μ − and the signal yields are extracted from a fit to(More)
We compute the static self-energy of SU(3) gauge theory in four spacetime dimensions to order α20 in the strong coupling constant α. We employ lattice regularization to enable a numerical simulation within the framework of stochastic perturbation theory. We find perfect agreement with the factorial growth of high order coefficients predicted by the(More)
Measurement of relative branching fractions of B decays to ψ(2S) and J /ψ mesons Abstract The relative rates of B-meson decays into J /ψ and ψ(2S) mesons are measured for the three decay modes in pp collisions recorded with the LHCb detector. The ratios of branching fractions (B) are measured to be B(B + → ψ(2S)K +) B(B + → J /ψK +) = 0.594 ± 0.006(stat) ±(More)
We determine the nonperturbative gluon condensate of four-dimensional SU(3) gauge theory in a model-independent way. This is achieved by carefully subtracting high-order perturbation theory results from nonperturbative lattice QCD determinations of the average plaquette. No indications of dimension-two condensates are found. The value of the gluon(More)
We present a new algorithm for the reduction of one-loop tensor Feynman integrals within the framework of the XLOOPS project, covering both mathematical and programming aspects. The new algorithm supplies a clean way to reduce the one-loop one-, two-and three-point Feynman integrals with arbitrary tensor rank and powers of the propagators to a basis of(More)
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