A meson-baryon molecular interpretation for some $\Omega_{c}$Ωc excited states

Abstract.We explore the possibility that some of the five narrow $\Omega_{c}$Ωc resonances recently observed at LHCb could correspond to pentaquark states, structured as meson-baryon bound states or molecules. The interaction of the low-lying pseudoscalar mesons with the ground-state baryons in the charm +1 , strangeness -2 and isospin 0 sector is built from t-channel vector meson exchange, using effective Lagrangians. The resulting s-wave coupled-channel unitarized amplitudes show the presence of two structures with similar masses and widths to those of the observed $\Omega_{c}(3050)^{0}$Ωc(3050)0 and $\Omega_{c}(3090)^{0}$Ωc(3090)0. The identification of these resonances with the meson-baryon bound states found in this work would also imply assigning the values $1/2^{-}$1/2- for their spin-parity. An experimental determination of the spin-parity of the $ \Omega_{c}(3090)^{0}$Ωc(3090)0 would contribute to a better understanding of its structure, as the quark-based models predict its spin-parity to be either $ 3/2^{-}$3/2- or $ 5/2^{-}$5/2-. Predictions for the analogue bottom $\Omega_{b}^{-}$Ωb- resonances are also given.