Narrow Results

Motivated by the heavy-flavor experiments at running Large Hadron Collider (LHC) and upgrading SuperKEKB, which provide abundant $\mathrm{{\rm Y}}$ data samples, the tree-dominated $\mathrm{{\rm Y}}(nS)\to B_c\rho$ and $B_c{K}^{\ast }$ (n =1, 2, 3) weak decays are studied within the framework of quantum chromodynamics (QCD) factorization. The QCD corrections to the longitudinal and transverse amplitudes are evaluated at next-to-leading order, and the branching fractions and polarization fractions are predicted. Numerically, the $\mathrm{{\rm Y}}(nS)\to B_c\rho$ decays have relatively large branching fractions at the order of ${𝒪}(10^{-10})$ and are in the scope of the LHC and SuperKEKB/Belle-II experiments.