Hadronic uncertainties in the $B\to K^*\mu^+\mu^-$ decay

TL;DR

This paper reviews the hadronic uncertainties affecting the angular observables in the decay K^*^+^+^- and discusses methods to extract non-factorizable contributions from experimental data, highlighting the potential to clarify current anomalies.

Contribution

The paper introduces a new parametrization to extract non-factorizable hadronic contributions from data, aiding in understanding the K^*^+^- anomaly.

Findings

Hadronic uncertainties could explain current measurements.

Future data may determine key hadronic parameters.

No definitive conclusion on the anomaly with current data.

Abstract

Motivated by the persisting 'anomaly' in the measurement of $P_5^\prime$, we review hadronic uncertainties entering the angular observables of the decay $\bar B\to {\bar K}^*\mu^+\mu^-$. We argue that hadronic uncertainties could account for the present measurements. We discuss how to extract information on the non-factorizable hadronic contribution from experimental data exploiting its $q^2$ dependence and propose a parametrization optimized for this purpose. While no clear conclusion can be drawn with present experimental uncertainties, we show that future measurements should be able to pin down many hadronic parameters that we define in our parametrization.