A note on Higgs decays into Z boson and J/Ψ(ϒ)

Rare decays h→ZV with V denoting the narrow cc^¯ or bb^¯ resonances, such as J/Ψ or ϒ states, have been analyzed. Within the standard model, these channels may proceed through the tree-level transition h→ZZ^⁎ with the virtual Z^⁎→V, and also loop-induced process h→Zγ^⁎, followed by γ^⁎→V. Our analysis shows that, for the bottomonium final states, the decay rate of h→Zϒ from the loop-induced process is small and the former transition gives the dominant contribution; while, for the charmonium final states, Γ(h→ZJ/Ψ) and Γ(h→ZΨ(2S)) induced by h→Zγ^⁎→ZV could be comparable to the contribution given by the tree-level h→ZZ^⁎→ZV transition