Understanding the low-lying Ω_c structures from a coupled-channel perspective

We perform a systematic analysis of the low-lying $\Omega_c$ structures in a coupled-channel approach. The couplings between meson-baryon channels, $\Xi_c \bar K$, $\Xi_c^{\prime} \bar K$, $\Xi_c^{*} \bar K$, $\Omega_c\eta$ and $\Omega_c^{*}\eta$, and three-quark bare states $\Omega_c(1P_\lambda)$ are considered. We predict a bound state $\Omega_c(2954)$ below the $\Xi_c \bar K$ threshold with $(J^P,j)=(1/2^-,0)$, which can be studied in the final states of $\Omega_c^{(*)} \pi$ and $\Omega_c^{(*)} \gamma$. Also, the resonances $\Omega_c(3000)$ and $\Omega_c(3050)$ can be classified as the lower $(J^P,j)=(1/2^-,1)$ and $(J^P,j)=(3/2^-,1)$ states, respectively. Our present assignments based on this coupled-channel perspective are significantly different from those of traditional three-quark picture and of molecular scenario. The future BelleII and LHCb experiments can search for the bound state $\Omega_c(2954)$ and measure the spin-parities of particles $\Omega_c(3000)$ and $\Omega_c(3050)$ to test our predictions.