Threshold effects as the origin of Zcs(4000), Zcs(4220) and X(4700) observed in B+→J/ψϕK

We investigate the B + → J / ψ ϕ K + decay via various rescattering diagrams. Without introducing genuine exotic resonances, it is shown that the Z cs ( 4000 ) , Z cs ( 4220 ) and X (4700) reported by the LHCb collaboration can be simulated by the J / ψ K ∗ + , ψ ′ K + and ψ ′ ϕ threshold cusps, respectively. These cusps are enhanced by some nearby triangle singularities. The X (4685) with J P = 1 + cannot be well simulated by the threshold effects in our model, which implies that it may be a genuine resonance.