The Double Strangeness Pentaquark and Other Exotic Hadrons in the Reaction ξb → j/ψφξ

Abstract

We study the possibility that four Ξ resonances (Ξ(1620), Ξ(1690), Ξ(1820), Ξ(1950)) could correspond to pentaquark states, in the form of a meson-baryon bound systems. We also explore the possible existence of doubly strange pentaquarks with hidden charm (Pcss) and find two candidates structured in a similar form, at energies of 4493 MeV and 4630 MeV. The meson-baryon interaction is built from t-channel meson exchange processes which are evaluated using effective Lagrangians. Moreover we analyse the Ξb → Ξ J/ψ ϕ decay process, which permits exploring the existence of the heavy double strange pentaquark, as well as other exotic hadrons, in the three different two-body invariant mass spectra of the emitted particles. In the J/ψϕ mass spectrum, we analyse the nature of the X(4140) and X(4160) resonances. In the J/ψΞ invariant mass spectrum, we study the signal produced by the doubly strange pentaquark, where we conclude that it has a good chance to be detected in this reaction if its mass is around 4580 − 4680 MeV. Finally, in the ϕΞ spectrum we study the likelihood to detect the Ξ(2500) state.