Semileptonic and nonleptonic decays of in the covariant light-front approach*

Abstract The semileptonic and nonleptonic decays of the b -flavor vector mesons and are investigated within the covariant light-front quark model (CLFQM). By calculating the form factors of the transitions under the CLFQM, with P denoting a pseudoscalar meson, i.e ., , we predict and discuss several physical observables, including the branching ratios, polarization fractions , and forward-backward asymmetries . The total widths of the single-photon radiative decay channels for these b-flavor vector mesons are estimated using their partial widths. In these considered decays, one can find that the semileptonic decays and , with being e or , and the nonleptonic channels have the largest branching ratios, which can reach up to the 10 -7 order, and are most likely to be accessible at the future high-luminosity LHCb and Belle-II experiments.