A search is presented for massive long-lived particles decaying into a muon and two quarks. The dataset consists of proton-proton interactions at centre-of-mass energies of 7 and 8 TeV, corresponding to integrated luminosities of 1 and 2, respectively. The analysis is performed assuming a set of production mechanisms with simple topologies, including the production of a Higgs-like particle decaying into two long-lived particles. The mass range from 20 to 80  and lifetimes from 5 to 100 are explored. Results are also interpreted in terms of neutralino production in different R-Parity violating supersymmetric models, with masses in the 23–198 GeV/ range. No excess above the background expectation is observed and upper limits are set on the production cross-section for various points in the parameter space of theoretical models.

A search for the rare decays B_{s}^{0}→τ^{+}τ^{-} and B^{0}→τ^{+}τ^{-} is performed using proton-proton collision data collected with the LHCb detector. The data sample corresponds to an integrated luminosity of 3  fb^{-1} collected in 2011 and 2012. The τ leptons are reconstructed through the decay τ^{-}→π^{-}π^{+}π^{-}ν_{τ}. Assuming no contribution from B^{0}→τ^{+}τ^{-} decays, an upper limit is set on the branching fraction B(B_{s}^{0}→τ^{+}τ^{-})<6.8×10^{-3} at the 95% confidence level. If instead no contribution from B_{s}^{0}→τ^{+}τ^{-} decays is assumed, the limit is B(B^{0}→τ^{+}τ^{-})<2.1×10^{-3} at the 95% confidence level. These results correspond to the first direct limit on B(B_{s}^{0}→τ^{+}τ^{-}) and the world's best limit on B(B^{0}→τ^{+}τ^{-}).

Using proton-proton collision data corresponding to an integrated luminosity of 3.0 fb −1 , recorded by the LHCb detector at center-of-mass energies of 7 and 8 TeV, the B þ c → D 0 K þ decay is observed with a statistical significance of 5.1 standard deviations. By normalizing to B þ →D 0 π þ decays, a measurement of the branching fraction multiplied by the production rates for B þ c relative to B þ mesons in the LHCb acceptance is obtained,−2.5 AE 0.6Þ × 10 −7 , where the first uncertainty is statistical and the second is systematic. This decay is expected to proceed predominantly through weak annihilation and penguin amplitudes, and is the first B To test QCD factorization and explore the new physics potential of B þ c decays, rarer decays such as suppressed tree-level b → u transitions and b → s loop-mediated (penguin) decays can be studied, where the charm quantum number remains unchanged. The simplest decay is the color-allowed

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A Dalitz plot analysis of decays is performed using data samples of pp collisions collected with the detector at centre-of-mass energies of and , corresponding to a total integrated luminosity of . A satisfactory description of the data is obtained when including a contribution representing an exotic resonant state. The significance of this exotic resonance is more than three standard deviations, while its mass and width are and , respectively. The spin-parity assignments and are both consistent with the data. In addition, the first measurement of the branching fraction is performed and gives where the first uncertainty is statistical, the second systematic, and the third is due to limited knowledge of external branching fractions.