Differential branching fraction and angular analysis of the decay $B^{0} \to K^{*0} \mu^{+}\mu^{-}$

TL;DR

This paper reports on the measurement of the differential branching fraction and angular observables of the decay $B^{0} o K^{*0} \mu^{+}\mu^{-}$ using LHCb data, including the first measurement of the zero-crossing point of the forward-backward asymmetry, which aligns with Standard Model predictions.

Contribution

It provides the first measurement of the zero-crossing point of the forward-backward asymmetry in this decay channel, using LHCb data at 7 TeV.

Findings

Zero-crossing point measured at $q_{0}^{2} = 4.9 \,\pm\ 0.9 \,\mathrm{GeV}^{2}/c^{4}$

Results are consistent with Standard Model predictions

Angular observables measured in bins of dimuon invariant mass squared

Abstract

The angular distribution and differential branching fraction of the decay $B^{0} \to K^{*0} \mu^{+}\mu^{-}$ are studied using a data sample, collected by the LHCb experiment in $pp$ collisions at $\sqrt{s}=7\,{\rm TeV}$, corresponding to an integrated luminosity of $1.0\,{\rm fb}^{-1}$. Several angular observables are measured in bins of the dimuon invariant mass squared, $q^{2}$. A first measurement of the zero-crossing point of the forward-backward asymmetry of the dimuon system is also presented. The zero-crossing point is measured to be $q_{0}^{2} = 4.9 \pm 0.9 \,{\rm GeV}^{2}/c^{4}$, where the uncertainty is the sum of statistical and systematic uncertainties. The results are consistent with the Standard Model predictions.