Abstract
The LHCb collaboration has recently presented their result on R K = ℬ(B + → K + μ + μ −)/ ℬ(B + → K + e + e −) for the dilepton invariant mass bin m 2 ℓℓ = 1 − 6 GeV2 (ℓ = μ, e). The measurement shows an intriguing 2.6σ deviation from the Standard Model (SM) prediction. In view of this, we study model independent New Physics (NP) explanations of R K consistent with other measurements involving b → sℓ + ℓ − transition, relaxing the assumption of lepton universality. We perform a Bayesian statistical fit to the NP Wilson Coefficients and compare the Bayes Factors of the different hypotheses in order to quantify their goodness-of-fit. We show that the data slightly favours NP in the muon sector over NP in the electron sector.
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Ghosh, D., Nardecchia, M. & Renner, S.A. Hint of lepton flavour non-universality in B meson decays. J. High Energ. Phys. 2014, 131 (2014). https://doi.org/10.1007/JHEP12(2014)131
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DOI: https://doi.org/10.1007/JHEP12(2014)131