Threshold effects as the origin of $$Z_{cs}(4000)$$ Z cs ( 4000 ) , $$Z_{cs}(4220)$$ Z cs ( 4220 ) and X(4700) observed in $$B^+\rightarrow J/\psi \phi K^+$$ B + → J / ψ ϕ K +

Abstract

Abstract We investigate the $$B^+\rightarrow J/\psi \phi K^+$$ 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 ( 4000 ) , $$Z_{cs}(4220)$$ Z cs ( 4220 ) and X(4700) reported by the LHCb collaboration can be simulated by the $$J/\psi K^{*+}$$ J / ψ K ∗ + , $$\psi ^\prime K^+$$ ψ ′ K + and $$\psi ^\prime \phi $$ ψ ′ ϕ threshold cusps, respectively. These cusps are enhanced by some nearby triangle singularities. The X(4685) with $$J^P=1^+$$ J P = 1 + cannot be well simulated by the threshold effects in our model, which implies that it may be a genuine resonance.