Probing hidden-charm decay properties of $P_c$ states in a molecular scenario

Abstract

The $P_c(4312)$, $P_c(4440)$, and $P_c(4457)$ observed by the LHCb Collaboration are very likely to be $S$-wave ${\Sigma }_c{\bar{D}}^{(\ast )}$ molecular candidates due to their near-threshold character. In this work, we study the hidden-charm decay modes of these $P_c$ states, $P_c\to J/\psi p({\eta }_{c}p)$, using a quark interchange model. The decay mechanism for the $P_c\to J/\psi p({\eta }_{c}p)$ processes arises from the quark-quark interactions, where all parameters are determined by the mass spectra of mesons. We present our results in two scenarios. In scenario I, we perform the dynamical calculations and treat the $P_c$ states as pure ${\Sigma }_c{\bar{D}}^{(\ast )}$ molecules. In scenario II, after considering the coupled channel effect between different flavor configurations ${\Sigma }_c^{(\ast )}{\bar{D}}^{(\ast )}$, we calculate these partial decay widths again. The decay patterns in these two scenarios can help us to explore the molecular assignment and the inner flavor configurations for the $P_c$ states. In particular, the decay widths of $\Gamma (P_c(4312)\to {\eta }_{c}p)$ are comparable to the $J/\psi p$ decay widths in both of these two scenarios. Future experiments like LHCb may confirm the existence of the $P_c(4312)$ in the ${\eta }_{c}p$ channel.

Comments: 13 pages, 7 figures, version published in PRD