Understanding B→J/ψϕ in the Standard Model

The rare decay B¯d0→J/ψϕ can proceed via four distinct mechanisms: (i) production of the ϕ via tri-gluon fusion, (ii) photoproduction of the J/ψ or ϕ, (iii) final-state rescattering of Ds(∗)Ds(∗) produced in the B¯d decay to J/ψϕ, and (iv) production of the ϕ via ω-ϕ mixing. In this work, we examined the contributions of photoproduction and final-state rescattering to B¯d0→J/ψϕ and found that the corresponding branching ratios were of the orders 10−11 and 10−9, respectively. Hence, this decay is dominated by the ω-ϕ mixing effect.