Analysis of hadronic coupling constants GB*cBc Υ, GB*cBcJ/ψ, GBcBc Υ and GBcBcJ/ψ with QCD sum rules

In this article, we study the momentum dependence of the hadronic coupling constants G(B*cBc) (Upsilon), G(B*cBcJ/psi), G(BcBc) (Upsilon,) and G(BcBcJ/psi) with the off-shell Upsilon and J/psi using the three-point QCD sum rules. Then we fit the hadronic coupling constants into analytical functions and extrapolate them into deep time-like regions to obtain the on-shell values G(B*cBc) (Upsilon)(q(2) = M-Upsilon(2)), G(B*cBcJ/psi)(q(2) = M-J/psi(2)), G(BcBc) (Upsilon)(q(2) = M-Upsilon(2)), and G(BcBcJ/psi)(q(2) = M-J/psi(2)) for the first time. These hadronic coupling constants can be taken as basic input parameters in phenomenological analyses.