Observation of X(3872) production in pp collisions at √s=7 TeV

Using 34.7 pb(-1) of data collected with the LHCb detector, the inclusive production of the X(3872) meson in pp collisions at root s = 7 TeV is observed for the first time. Candidates are selected in the X(3872) -> J/psi pi(+)pi(-) decay mode, and used to measure sigma(pp -> X(3872) + anything)beta(X(3872) -> J/psi pi(+)pi(-)) = 5.4 +/- 1.3 (stat)+/- 0.8 (syst) nb, where sigma (pp -> X(3872) + anything) is the inclusive production cross section of X(3872) mesons with rapidity in the range 2.5-4.5 and transverse momentum in the range 5-20 GeV/c. In addition the masses of both the X(3872) and psi(2S) mesons, reconstructed in the J/psi pi(+)pi(-) final state, are measured to be m(X(3872)) = 3871.95 +/- 0.48 (stat)+/- 0.12 (syst) MeV/c(2) and m(psi(2S)) = 3686.12 +/- 0.06 (stat)+/- 0.10 (syst) MeV/c(2).