We present a global analysis of the $B\to K^{*}(\to K\pi ){\mu }^{+}{\mu }^{-}$ decay using the recent LHCb measurements of the primary observables $P_{1,2}$ and $P_{4,5,6,8}^{\prime }$. Some of them exhibit large deviations with respect to the Standard Model (SM) predictions. We explain the observed pattern of deviations through a large new physics contribution to the Wilson coefficient of the semileptonic operator ${\mathcal{O}}_9$. This contribution has an opposite sign to the SM one, i.e., reduces the size of this coefficient significantly. A good description of data is achieved by allowing for new physics contributions to the Wilson coefficients ${\mathcal{C}}_7$ and ${\mathcal{C}}_9$ only. We find a $4.5\sigma$ deviation with respect to the SM prediction, combining the large-recoil $B\to K^{*}(\to K\pi ){\mu }^{+}{\mu }^{-}$ observables with other radiative processes. Once low-recoil observables are included the significance gets reduced to $3.9\sigma$. We have tested different sources of systematics, none of them modifying our conclusions significantly. Finally, we propose additional ways of measuring the primary observables through new foldings.

• Received 2 August 2013

DOI:https://doi.org/10.1103/PhysRevD.88.074002