Hidden charm pentaquark states and ${\Sigma }_c^{(\ast )}{\bar{D}}^{(\ast )}$ interaction in chiral perturbation theory

Abstract

We adopt the chiral perturbation theory to calculate the ${\Sigma }_c^{(\ast )}{\bar{D}}^{(\ast )}$ interaction to the next-to-leading order (NLO) and include the couple-channel effect in the loop diagrams. We reproduce the three $P_c$ states in the molecular picture after including the ${\Lambda }_c{\bar{D}}^{(\ast )}$ intermediate states. We also discuss some novel observations arising from the loop diagrams.

Comments: 5 pages, 5 figures; contribution to the proceedings of the XVIII International Conference on Hadron Spectroscopy and Structure, HADRON-2019. August 16-21, Guilin, China