Speaker
Michele Mantovano
(University and INFN Trieste)
Description
The Belle and Belle$~$II experiments have collected a 1.1$~$ab$^{-1}$ sample of $e^+ e^-\to B\bar{B}$ collisions at the $\Upsilon(4S)$ resonance. These data, with low particle multiplicity, constrained initial state kinematics and excellent lepton identification, are an ideal environment to study lepton-flavour universality in semileptonic decays of the $B$ meson. We present results on the ratios of semitauonic decay rates to semileptonic decays with light leptons, in both exclusive and inclusive $B$ decays. We also present measurements of angular observables that test universality between electrons and muons.
Primary authors
Michele Mantovano
(University and INFN Trieste)
Sven Vahsen
(University of Hawaii (US))