%0 Journal Article
%T Study of eta-eta ' mixing from measurement of B-(s)(0) -> J/psi eta((')) decay rates
%A LHCb Collaboration (Aaij, R. et al
%A Martinez-Vidal, F.
%A Oyanguren, A.
%A Ruiz Valls, P.
%A Sanchez Mayordomo, C.
%J Journal of High Energy Physics
%D 2015
%V 01
%N 1
%I Springer
%@ 1029-8479
%G English
%F LHCbCollaborationAaij_etal2015
%O WOS:000347685500001
%O exported from refbase (https://references.ific.uv.es/refbase/show.php?record=2077), last updated on Thu, 05 Feb 2015 15:02:42 +0000
%X A study of B and B-s(0) meson decays into J/psi eta and J/psi eta' 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/psi eta' is observed for the first time. The following ratios of branching fractions are measured: B(B-0 -> J psi eta')/B(B-s(0) -> J psi eta') = (2.28 +/- 0.65 (stat) +/- 0.010 (syst) +/- 0.13 (f(s)/f(d)) x 10(-2) , B(B-0 -> J psi eta')/B(B-s(0) -> J psi eta') = (1.85 +/- 0.65 (stat) +/- 0.09 (syst) +/- 0.11 (f(s)/f(d)) x 10(-2) 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(0) or a B-0 meson. The branching fraction ratios are used to determine the parameters of eta-eta' meson mixing. In addition, the first evidence for the decay B-s(0) -> psi(2S)' is reported, and the relative branching fraction is measured, B(B-s(0) -> psi(2S)eta')/B(B-s(0) -> J psi eta') = (38.7 +/- 9.0 (stat) +/- 1.3 (syst) +/- 0.9(B)) x 10(-2), where the third uncertainty is due to the limited knowledge of the branching fractions of J/psi and psi(2S) mesons.
%K Spectroscopy
%K Hadron-Hadron Scattering
%K QCD
%K Branching fraction
%K B physics
%R 10.1007/JHEP01(2015)024
%U http://arxiv.org/abs/1411.0943
%U https://doi.org/10.1007/JHEP01(2015)024
%P 024-24pp