# Study of $\bar{B}_{u,d,s}^* \to D_{u,d,s}^* V\,(V=D_{d,s}^{*-}\,,K^{*-}\,,{\rho}^-)$ weak decays

## TL;DR

This paper investigates the weak decays of excited B mesons into D* mesons and vector mesons using the factorization approach, calculating form factors and helicity amplitudes to predict decay rates relevant for future experiments.

## Contribution

It provides the first detailed analysis of $ar{B}^*$ to D*V decays, including form factors, helicity amplitudes, and branching fractions within the covariant light-front quark model.

## Key findings

- Hierarchy in helicity amplitudes identified
- Branching fractions for certain decays estimated to be above 10^{-8}
- Decays are promising for observation at LHC and Belle-II

## Abstract

Motivated by the rapid development of heavy flavor physics experiment, we study the tree-dominated nonleptonic $\bar{B}_{u,d,s}^* \to D_{u,d,s}^*V$~($V=D^{*-},D_s^{*-},K^{*-},{\rho}^-$) decays within the factorization approach. The relevant transition form factors are calculated by employing the covariant light-front quark model. The helicity amplitudes are calculated and analyzed in detail, and a very clear hierarchy structure $ |H_{-0}| \approx 2|H_{00}| > |H_{0-}|\approx|H_{--}|>|H_{0+}|\approx|H_{++}|$ is presented. The branching fractions are computed and discussed. Numerically, the CKM-favored $\bar{B}^*_q\to D^*_q \rho^{-}$ and $D^*_q D_s^{*-}$ decays have relatively large branching fractions, $\gtrsim {\cal O}(10^{-8})$, and are hopeful to be observed by LHC and Belle-II experiments in the future.