%0 Journal Article
%T Test of lepton universality with B-0 -> K*(0)l(+)l(-) decays
%A LHCb Collaboration (Aaij, R. et al
%A Garcia Martin, L. M.
%A Henry, L.
%A Martinez-Vidal, F.
%A Oyanguren, A.
%A Remon Alepuz, C.
%A Ruiz Valls, P.
%A Sanchez Mayordomo, C.
%J Journal of High Energy Physics
%D 2017
%V 08
%N 8
%I Springer
%@ 1029-8479
%G English
%F LHCbCollaborationAaij_etal2017
%O WOS:000410888900003
%O exported from refbase (https://references.ific.uv.es/refbase/show.php?record=3302), last updated on Wed, 04 Oct 2017 08:53:33 +0000
%X A test of lepton universality, performed by measuring the ratio of the branching fractions of the B-0 -> K*(0)mu(+) mu(-) and B-0 -> K*e(+)e(-) decays, R-K*0, is presented. The K*(0) meson is reconstructed in the final state K+pi(-), which is required to have an invariant mass within 100 MeV/c(2) of the known K*(892)(0) mass. The analysis is performed using proton-proton collision data, corresponding to an integrated luminosity of about 3 fb(-1), collected by the LHCb experiment at centre-of-mass energies of 7 and 8 TeV. The ratio is measured in two regions of the dilepton invariant mass squared, q(2), to be R-K*0 – {0.66(-0.007)(+0.11)(stat) +/- 0.03(syst) for 0.045 < q(2) < GeV2/c(4), 0.69(-0.07)(+0.11)(stat) +/- 0.05(syst) for 1.1 < q(2) < 6.0 GeV2/c(4). The corresponding 95.4% confidence level intervals are [0.52, 0.89] and [0.53, 0.94]. The results, which represent the most precise measurements of R-K*0 to date, are compatible with the Standard Model expectations at the level of 2.1-2.3 and 2.4-2.5 standard deviations in the two q(2) regions, respectively.
%K B physics
%K Branching fraction
%K Hadron-Hadron scattering (experiments)
%K Rare decay
%R 10.1007/JHEP08(2017)055
%U http://arxiv.org/abs/1705.05802
%U https://doi.org/10.1007/JHEP08(2017)055
%P 055-31pp