Angular analysis of the B$^0$ $\to$ K$^*$(892)$^0\mu^+\mu^-$ decay in proton-proton collisions at $\sqrt{s}$ = 13 TeV

Abstract

A full set of optimized observables is measured in an angular analysis of the decay B$^0$ $\to$ K$^*$(892)$^0\mu^+\mu^-$ using a sample of proton-proton collisions at $\sqrt{s}$ = 13 TeV, collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 140 fb$^{-1}$. The analysis is performed in six bins of the squared invariant mass of the dimuon system, $q^2$, over the range 1.1 $\lt$ $q^2$ $\lt$ 16 GeV$^2$. The results are among the most precise experimental measurements of the angular observables for this decay and are compared to a variety of predictions based on the standard model. Some of these predictions exhibit tension with the measurements.