1 research outputs found
Measurement of Angular Coefficients of : Implications for and Tests of Lepton Flavor Universality
We measure the complete set of angular coefficients for exclusive
decays (). Our analysis
uses the full Belle data set with hadronic tag-side
reconstruction. The results allow us to extract the form factors describing the
transition and the Cabibbo-Kobayashi-Maskawa matrix element
. Using recent lattice QCD calculations for the hadronic form
factors, we find using the BGL
parameterization, compatible with determinations from inclusive semileptonic
decays. We search for lepton flavor universality violation as a function of the
hadronic recoil parameter , and investigate the differences of the electron
and muon angular distributions. We find no deviation from Standard Model
expectations