Measurement of Angular Coefficients of B ¯ →d∗ℓ ν ¯ ℓ: Implications for |Vcb | and Tests of Lepton Flavor Universality
Journal
Physical Review Letters
Journal Volume
133
Journal Issue
13
Start Page
131801
ISSN
0031-9007
1079-7114
Date Issued
2024-09-24
Author(s)
Abstract
We measure the complete set of angular coefficients Ji for exclusive B¯→D∗ℓν¯ℓ decays (ℓ=e, μ). Our analysis uses the full 711 fb-1 Belle dataset with hadronic tag-side reconstruction. The results allow us to extract the form factors describing the B¯→D∗ transition and the Cabibbo-Kobayashi-Maskawa matrix element |Vcb|. Using recent lattice QCD calculations for the hadronic form factors, we find |Vcb|=(40.7±0.7)×10-3 using the Boyd-Grinstein-Lebed parametrization, compatible with determinations from inclusive semileptonic decays. We search for lepton flavor universality violation as a function of the hadronic recoil parameter w and investigate the differences of the electron and muon angular distributions. We find no deviation from standard model expectations.
Publisher
American Physical Society (APS)
Type
journal article