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Associated production of bottomonia and open charm hadrons inppcollisions at√s̅=7and8 TeV is observed using data corresponding to an integrated luminosity of 3 fb⁻¹accumulated with the LHCb detector. The observation of five combinations,Υ(1S)D⁰ ,Υ(2S)D⁰ ,Υ(1S)D⁺ ,Υ(2S)D⁺andΥ(1S)D⁺_(s) , is reported. Production cross-sections are measured forΥ(1S)D⁰andΥ(1S)D⁺pairs in the forward region. The measured cross-sections and the differential distributions indicate the dominance of double parton scattering as the main production mechanism. This allows a precise measurement of the effective cross-section for double parton scattering.

The first model-independent measurement of the charm mixing parameters in the decayD⁰ → K_(S) π⁺ π⁻is reported, using a sample ofppcollision data recorded by the LHCb experiment, corresponding to an integrated luminosity of 1.0 fb ⁻¹at a centre-of-mass energy of 7 TeV. The measured values are eqnarray* x &=& (+0.86 0.53 0.17) 10⁻2, y &=& (+0.03 0.46 0.13) 10⁻2, eqnarray* where the first uncertainties are statistical and include small contributions due to the external input for the strong phase measured by the CLEO collaboration, and the second uncertainties are systematic. The results are consistent with the current world averages.

Production cross-sections of prompt charm mesons are measured with the first data from$pp$collisions at the LHC at a centre-of-mass energy of$13\\,\\mathrm{TeV}$ . The data sample corresponds to an integrated luminosity of$4.98 \\pm 0.19\\,\\mathrm{pb}^{-1}$collected by the LHCb experiment. The production cross-sections of$D^{0}$ ,$D^{+}$ ,$D_{s}^{+}$ , and$D^{*+}$mesons are measured in bins of charm meson transverse momentum,$p_{\\mathrm{T}}$ , and rapidity,$y$ , and cover the range$0 < p_{\\mathrm{T}} < 15\\,\\mathrm{GeV}/c$and$2.0 < y < 4.5$ . The ratios of the integrated cross-sections between charm mesons agree with previously measured fragmentation fractions. The inclusive$c\\overline{c}$cross-section within the range of$0 < p_{\\mathrm{T}} < 8\\,\\mathrm{GeV}/c$is found to be \\[ (pp ccX) = 2940 3 180 160\\, \\] where the uncertainties are due to statistical, systematic and fragmentation fraction uncertainties, respectively.

TheB_(s)⁰ → J/ψ φ φdecay is observed inppcollision data corresponding to an integrated luminosity of 3 fb ⁻¹recorded by the LHCb detector at centre-of-mass energies of 7 TeV and 8 TeV. This is the first observation of this decay channel, with a statistical significance of 15 standard deviations. The mass of theB_(s)⁰meson is measured to be5367.08 ± 0.38 ± 0.15MeV/c ² . The branching fraction ratio𝓑(B_(s)⁰ → J/ψ φ φ)/𝓑(B_(s)⁰ → J/ψ φ)is measured to be0.0115 ± 0.0012 ^(+0.0005)_(-0.0009) . In both cases, the first uncertainty is statistical and the second is systematic. No evidence for non-resonantB_(s)⁰ → J/ψ φ K⁺ K⁻orB_(s)⁰ → J/ψ K⁺ K⁻ K⁺ K⁻decays is found.

An angular analysis of the$B^{0}\\rightarrow K^{*0}(\\rightarrow K^{+}\\pi^{-})\\mu^{+}\\mu^{-}$decay is presented. The dataset corresponds to an integrated luminosity of$3.0\\,{\\mbox{fb}^{-1}}$of$pp$collision data collected at the LHCb experiment. The complete angular information from the decay is used to determine$C\\!P$ -averaged observables and$C\\!P$asymmetries, taking account of possible contamination from decays with the$K^{+}\\pi^{-}$system in an S-wave configuration. The angular observables and their correlations are reported in bins of$q^2$ , the invariant mass squared of the dimuon system. The observables are determined both from an unbinned maximum likelihood fit and by using the principal moments of the angular distribution. In addition, by fitting for$q^2$ -dependent decay amplitudes in the region$1.1

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