An angular analysis of the B 0 → K *0(→ K + π −)μ + μ − decay is presented. The dataset corresponds to an integrated luminosity of 3.0 fb−1 of pp collision data collected at the LHCb experiment. The complete angular information from the decay is used to determine CP-averaged observables and CP asymmetries, taking account of possible contamination from decays with the K + π − 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 < q 2 < 6.0 GeV2/c 4, the zero-crossing points of several angular observables are computed. A global fit is performed to the complete set of CP-averaged observables obtained from the maximum likelihood fit. This fit indicates differences with predictions based on the Standard Model at the level of 3.4 standard deviations. These differences could be explained by contributions from physics beyond the Standard Model, or by an unexpectedly large hadronic effect that is not accounted for in the Standard Model predictions

The Ξ_{c}^{+}K^{-} mass spectrum is studied with a sample of pp collision data corresponding to an integrated luminosity of 3.3  fb^{-1}, collected by the LHCb experiment. The Ξ_{c}^{+} is reconstructed in the decay mode pK^{-}π^{+}. Five new, narrow excited Ω_{c}^{0} states are observed: the Ω_{c}(3000)^{0}, Ω_{c}(3050)^{0}, Ω_{c}(3066)^{0}, Ω_{c}(3090)^{0}, and Ω_{c}(3119)^{0}. Measurements of their masses and widths are reported.

A search for a long-lived scalar particle χ is performed, looking for the decay B þ → K þ χ with χ → μ þ μ − in pp collision data corresponding to an integrated luminosity of 3 fb −1 , collected by the LHCb experiment at center-of-mass energies of ffiffi ffi s p ¼ 7 and 8 TeV. This new scalar particle, predicted by hidden sector models, is assumed to have a narrow width. The signal would manifest itself as an excess in the dimuon invariant mass distribution over the Standard Model background. No significant excess is observed in the accessible ranges of mass 250 < mðχÞ < 4700 MeV=c 2 and lifetime 0.1 < τðχÞ < 1000 ps. Upper limits on the branching fraction BðB þ → K þ χðμ þ μ − ÞÞ at 95% confidence level are set as a function of mðχÞ and τðχÞ, varying between 2 × 10 −10 and 10 −7. These are the most stringent limits to date. The limits are interpreted in the context of a model with a light inflaton particle.

From samples of pp collision data collected by the LHCb experiment at ffiffi ffi s p ¼ 7, 8 and 13 TeV, corresponding to integrated luminosities of 1.0, 2.0 and 1.5 fb −1 , respectively, a peak in both the Λ In the constituent quark model [1,2], baryonic states form multiplets according to the symmetry of their flavor, spin, and spatial wave functions. The masses, widths, and decay modes of these states give insight into their internal structure [3]. The Ξ − mass or width determination, as they have larger systematic uncertainties due to modeling of the mass resolution.The LHCb detector [25,26] is a single-arm forward spectrometer covering the pseudorapidity range 2 < η < 5, designed for the study of particles containing b or c quarks [25,26]. Events are selected online by a trigger, which consists of a hardware stage, based on information from the calorimeter and muon systems, followed by a software stage, which applies a full event reconstruction [27,28].

No abstract