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The polarisation of prompt ψ ( 2 S ) mesons is measured by performing an angular analysis of ψ ( 2 S ) → μ + μ - decays using proton-proton collision data, corresponding to an integrated luminosity of 1.0 fb - 1 , collected by the LHCb detector at a centre-of-mass energy of 7 TeV. The polarisation is measured in bins of transverse momentum p T and rapidity y in the kinematic region 3.5 < p T < 15 GeV / c and 2.0 < y < 4.5 , and is compared to theoretical models. No significant polarisation is observed.

A bstract Time-integrated CP asymmetries in D 0 decays to the final states K − K + and π − π + are measured using proton-proton collisions corresponding to 3fb −1 of integrated luminosity collected at centre-of-mass energies of 7 TeV and 8 TeV. The D 0 mesons are produced in semileptonic b -hadron decays, where the charge of the accompanying muon is used to determine the initial flavour of the charm meson. The difference in CP asymmetries between the two final states is measured to be Δ A CP = A CP K − K + − A CP π − π + = + 0.14 ± 0.16 stat ± 0.08 syst % . A measurement of A CP ( K − K + ) is obtained assuming negligible CP violation in charm mixing and in Cabibbo-favoured D decays. It is found to be A CP K − K + = − 0.06 ± 0.15 stat ± 0.10 syst % , where the correlation coefficient between Δ A CP and A CP ( K − K + ) is ρ = 0 . 28. By combining these results, the CP asymmetry in the D 0 → π − π + channel is A CP ( π − π + ) = (−0 . 20 ± 0 . 19 (stat) ± 0 . 10 (syst))%.

A bstract The kinematic dependences of the relative production rates, f Λ b 0 / f d , of Λ b 0 baryons and B 0 mesons are measured using Λ b 0  →  Λ c + π − and B ¯ 0 → D + π − decays. The measurements use proton-proton collision data, corresponding to an integrated luminosity of 1 fb −1 at a centre-of-mass energy of 7 TeV, recorded in the forward region with the LHCb experiment. The relative production rates are observed to depend on the transverse momentum, p T , and pseudorapidity, η , of the beauty hadron, in the studied kinematic region 1 . 5 < p T < 40 GeV /c and 2 < η < 5. Using a previous LHCb measurement of f Λ b 0 / f d in semileptonic decays, the branching fraction ℬ( Λ b 0  →  Λ c + π − ) = (4.30 ± 0.03 − 0.11 + 0.12  ± 0.26 ± 0.21) × 10 − 3 is obtained, where the first uncertainty is statistical, the second is systematic, the third is from the previous LHCb measurement of f Λ b 0 / f d and the fourth is due to the b B ¯ 0 → D + π − branching fraction. This is the most precise measurement of a Λ b 0 branching fraction to date.

A bstract An angular analysis of the decay B 0 → ϕK * (892) 0 is reported based on a pp collision data sample, corresponding to an integrated luminosity of 1 . 0 fb −1 , collected at a centre-of-mass energy of = 7 TeV with the LHCb detector. The P-wave amplitudes and phases are measured with a greater precision than by previous experiments, and confirm about equal amounts of longitudinal and transverse polarization. The S-wave K + π − and K + K − contributions are taken into account and found to be significant. A comparison of the B 0 → ϕK * (892) 0 and results shows no evidence for direct CP violation in the rate asymmetry, in the triple-product asymmetries or in the polarization amplitudes and phases.