Tetraquark interpretation of the charged bottomonium-like statesZb±(10610)andZb±(

The hidden-charm pentaquark and tetraquark states

“…Later in Ref. [446], Ali, Hambrock, and Wang reproduced the observed masses of the Z b (10610) and Z b (10650) in terms of the decay widths for the h b (2P)π ± . They obtained a ratio for the relative decay amplitudes in the decays Z b (10610)/Z b (10650) → h b (mP)π ± , which agrees with the experimental data [172].…”

Interpretation of the newly observed Ωc0 resonances

“…where the parameters are adopted as (κ bs )3 = 25±2MeV, A b (Ω b ) = 5±2MeV, and B(Ω b ) = 408±4MeV [19,20,22]. Since the observed spin-orbitally splitting in the Ξ − b (X) states is limited, we only give the approximate error and will discuss the uncertainties of the coupling constants in future works.…”

“…The strength of the attractive force between two quarks is reflected by a coupling constant as given below. A fit of the experimental data have indicated that the coupling constant for the two strange quarks is much larger than that for the cs system, for instance, κ ss = 72MeV and κ cs (24 − 25)MeV [18][19][20]. Following this scheme, we will treat the charmed doubly strange baryons as heavy-quark-light-diquark bound states in order to explain the newly observed five narrow Ω 0 c (X) states.…”

Heavy quark spin structure in Z_b resonances

“…Their dynamical model, however, is an open question. Proposed interpretations include presence of the compact tetraquark [9], non-resonant rescattering [10], multiple rescatterings that result in the amplitude pole known as coupled channel resonance [11] and deutron-like molecule bound by meson exchanges [12]. All these mechanisms (except for the tetraquark) are intimately related and correspond rather to quantitative than to qualitative differences.…”