The $B(B_s)\to D_{(s)}({\bar{D}}_{(s)})T$ and $D_{(s)}^{\ast }({\bar{D}}_{(s)}^{\ast })T$ decays in perturbative QCD approach

Abstract

In perturbative QCD approach, we investigate the $B(B_s)\to D_{(s)}({\bar{D}}_{(s)})T$ and $D_{(s)}^{\ast }({\bar{D}}_{(s)}^{\ast })T$ decays, which include the Cabibbo-Kobayashi-Maskawa (CKM) favored decays and the Cabibbo-Kobayashi-Maskawa-suppressed decays, where T denotes a light tensor meson. From our calculation, we find that the nonfactorizable emission diagrams and the annihilation type diagrams are important, especially for those color suppressed channels. For those decays with a tensor meson emitted, the factorizable emission diagrams vanish owing to the fact that a tensor meson can not be produced through the local (V-A) or tensor current. The numerical results show that the predictions for the branching ratios of considered charmed B decays are in the range of $10^{-4}$ to $10^{-6}$ for those CKM-favored decays (governed by $|V_{cb}|$) and in the range of $10^{-5}$ to $10^{-8}$ for those CKM-suppressed decays (governed by $|V_{ub}|$). We also predict large transverse polarization contributions in many of the $B(B_s)\to D_{(s)}^{\ast }({\bar{D}}_{(s)}^{\ast })T$ decay channels.

Comments: 30 pages, 3 figures, typos correctet in Figs. 1 and 2