Abstract
A study of B and Bs 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 B0 → J/ψ η′ is observed for the first time. The following ratios of branching fractions are measured:
where the third uncertainty is related to the present knowledge of fs/fd, the ratio between the probabilities for a b quark to form a Bs or a B0 meson. The branching fraction ratios are used to determine the parameters of η − η′ meson mixing. In addition, the first evidence for the decay Bs → ψ(2S)η′ is reported, and the relative branching fraction is measured,
where the third uncertainty is due to the limited knowledge of the branching fractions of J/ψ and ψ(2S) mesons.
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The LHCb collaboration., Aaij, R., Adeva, B. et al. Study of η − η′ mixing from measurement of B 0(s) → J/ψη(′) decay rates. J. High Energ. Phys. 2015, 24 (2015). https://doi.org/10.1007/JHEP01(2015)024
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DOI: https://doi.org/10.1007/JHEP01(2015)024