Abstract: A study of B and B s meson decays into J/ψ η and J/ψ η ′ final states is performed using a data set of proton-proton collisions at centre-of-mass energies of 7 and 8 TeV, collected by the LCHb experiment and corresponding to 3.0 fb −1 of integrated luminosity. The decay B 0 → J/ψ η ′ is observed for the first time. The following ratios of branching fractions are measured: (Formula Presented) where the third uncertainty is related to the present knowledge of f s/f d, the ratio between the probabilities for a b quark to form a B s or a B 0 meson. The branching fraction ratios are used to determine the parameters of η − η ′ meson mixing. In addition, the first evidence for the decay B s → ψ(2S)η ′ is reported, and the relative branching fraction is measured, (Formula Presented) where the third uncertainty is due to the limited knowledge of the branching fractions of J/ψ and ψ(2S) mesons.
All Science Journal Classification (ASJC) codes
- Nuclear and High Energy Physics