The Bd↦ K* μ+_{} μ-_{} decay: A study in the Standard Model

The rare semileptonic B_d↦ K^* μ⁺_{} μ^-_{} decay has been extensively studied within the Standard Model and beyond. Recently, data provided by the LHCb experiment suggested the presence of new physics given the discrepancy found between the theoretical and the experimental value of a certain observable ( P'₅) at low q². This requires a careful re-examination of the Standard Model estimates so that a discrimination between the latter and any model of new physics can be made. We present in this work a Bayesian analysis of the decay in the full range of q², in which we perform a full fit from available data. We also make well-motivated arguments about the size of the hadronic uncertainties and ultimately study the compatibility of the currently available experimental data with the Standard Model predictions.