# name
Study of η − η′ mixing from measurement of B (s)0 → J/ψη(′) decay rates

# metadata.dc.description.abstract[].value
A study of B and B0 s meson decays into J/ψη and J/ψη0 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/ψη0 is observed for the first time. The following ratios of branching fractions are measured: B(B0 → J/ψη0 ) B(B0 s → J/ψη0) = (2.28 ± 0.65 (stat) ± 0.10 (syst) ± 0.13 (fs/fd)) × 10−2 , B(B0 → J/ψη) B(B0 s → J/ψη) = (1.85 ± 0.61 (stat) ± 0.09 (syst) ± 0.11 (fs/fd)) × 10−2 , 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 B0 s or a B0 meson. The branching fraction ratios are used to determine the parameters of η−η 0 meson mixing. In addition, the first evidence for the decay B0 s → ψ(2S)η 0 is reported, and the relative branching fraction is measured, B(B0 s → ψ(2S)η 0 ) B(B0 s → J/ψη0) = (38.7 ± 9.0 (stat) ± 1.3 (syst) ± 0.9(B)) × 10−2 , where the third uncertainty is due to the limited knowledge of the branching fractions of J/ψ and ψ(2S) mesons.

# metadata.dc.relation.ispartof[].value
Journal of High Energy Physics, 2015, vol. 2015, num. 24, p. 1-24

# metadata.dc.rights[].value
cc-by (c) Garrido Beltrán, Lluis et al., 2015

# metadata.dc.source[].value
Articles publicats en revistes (Física Quàntica i Astrofísica)

# metadata.dc.subject.other[].value
Large Hadron Collider (France and Switzerland)

# metadata.dc.title[].value
Study of η − η′ mixing from measurement of B (s)0 → J/ψη(′) decay rates