Abstract
There are some slight tensions with the SM predictions within the latest LHCb measurements. Besides the known anomaly in one angular observable of the rare decay B → K * μ + μ −, another small discrepancy recently occurred. The ratio R K = BR(B + → K + μ + μ −)/BR(B + → K + e + e −) in the low-q 2 region has been measured by LHCb showing a 2.6σ deviation from the SM prediction. In contrast to the anomaly in the rare decay B → K * μ + μ − which is affected by power corrections, the ratio R K is theoretically rather clean. We analyse all the b → sℓℓ data with global fits and in particular explore the possibility of breaking of lepton universality. Possible cross-checks with an analysis of the inclusive B → X s ℓ + ℓ − decay are also explored.
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Hurth, T., Mahmoudi, F. & Neshatpour, S. Global fits to b → sℓℓ data and signs for lepton non-universality. J. High Energ. Phys. 2014, 53 (2014). https://doi.org/10.1007/JHEP12(2014)053
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DOI: https://doi.org/10.1007/JHEP12(2014)053