Systematic analysis of the transition form factors of B to D-wave charmonia and corresponding semileptonic decays

In this article, the vector, axial vector and tensor form factors of Bc to D-wave charmonia ψJ (J=1,2,3) and ηc2 are analyzed within the framework of three-point QCD sum rules. With the predicted vector and axial vector form factors, we study the decay widths and branching ratios of semileptonic decays Bc→ψJlνl¯ and Bc→ηc2lνl¯. Our results indicate that the semileptonic decay branching ratios of Bc to D-wave charmonia decreases as the total angular momentum of the final state D-wave charmonia increases. For decay processes Bc→ψ1lν¯l, Bc→ψ2[ηc2]lν¯l and Bc→ψ3lν¯l, the branching ratios can reach the order of magnitude 10−3, 10−4 and 10−5, respectively, which can provide a valuable reference for future experimental measurements for Bc meson by LHCb collaboration. Furthermore, these results also can provide useful information to study the properties of Bc meson and D-wave charmonia.