Data-driven analyses and model-independent fits for present $b\to s \ell \ell$ results
Résumé
We present a critical assessment of the present $B$ anomalies in the exclusive $b \to s \ell\ell$ mode based on the QCD factorisation approach (QCDf). In particular, we analyse the impact of different local form factor calculations and of the largest bin in the low-$q^2$ region. We also present a model-independent analysis of the new results of the CMS experiment on the $B \to K^* μ^+μ^-$ angular observables and compare them with the corresponding LHCb data. In addition, we update the global fit by including all $b \to s$ observables incorporating the new data from CMS. In these analyses, we use 10% or higher guesstimates of the non-factorisable power corrections as additional uncertainties, serving as a placeholder for robust estimates of these contributions. Updating earlier results, we also analyse the combined LHCb and CMS data on the $B \to K^* μ^+μ^-$ angular observables using data-driven approaches to find indications whether these tensions between the QCDf predictions and the present data are due to underestimated subleading hadronic contributions or due to new physics effects.