Study of the ${\Upsilon}(1S)$ ${\to}$ $B_{c}D_{s}^{\ast}$ decay with pQCD approach

TL;DR

This paper investigates the rare decay of the bottomonium state ${5}(1S)$ into $B_c$ and $D_s^*$ mesons using perturbative QCD, highlighting the dominant helicity amplitudes and potential experimental observability.

Contribution

First study of the ${5}(1S)$ ${ o}$ $B_c D_s^*$ decay using pQCD, analyzing polarization and wave function sensitivities.

Findings

Branching ratio up to 10^{-9}

Longitudinal and parallel helicity amplitudes dominate

Decay sensitive to meson wave functions

Abstract

The ${\Upsilon}(1S)$ ${\to}$ $B_{c}D_{s}^{\ast}$ weak decay is studied with the perturbative QCD approach firstly. It is found that (1) main contributions to branching ratio come from the longitudinal and parallel helicity amplitudes, (2) branching ratio, longitudinal and parallel polarization fractions are sensitive to the wave functions of the ${\Upsilon}(1S)$ meson, (3) branching ratio for the ${\Upsilon}(1S)$ ${\to}$ $B_{c}D_{s}^{\ast}$ decay can reach up to $10^{-9}$, which might be promisingly measured by the future experiments.