Pentaquark interpretation of Lambda _{c} states in the quark model

Abstract

Motivated by the recent observation of the Lambda _c(2910)^+ state in the Sigma _{c}(2455)^{0,++}pi ^{pm } spectrum by the Belle Collaboration, we investigate the explanation of Lambda _{c} states within the pentaquark framework using the quark delocalization color screening model (QDCSM). To check for bound states and resonance states, we utilize the real-scaling method. Additionally, we calculate the root mean square of cluster spacing to study the structure of the states and further estimate whether a state is a resonance state or not. Our numerical results show that Lambda _{c}(2910) cannot be interpreted as a molecular state, and Sigma _{c}(2800) cannot be explained as the ND molecular state with J^P=1/2^-. However, we find that Lambda _{c}(2595) can be interpreted as a molecular state with J^P=frac{1}{2}^-, where the main component is Sigma _{c}pi . Similarly, we interpret Lambda _{c}(2625) as a molecular state with J^P=frac{3}{2}^-, where the main component is Sigma _{c}^{*}pi . We also suggest that Lambda _{c}(2940) is likely to be interpreted as a molecular state with J^P=3/2^-, where the main component is ND^{*}. In addition, we predict two new states: a J^P=3/2^-Sigma _{c}rho resonance state with a mass of 3140–3142 MeV, and a J^P=frac{5}{2}^-Sigma _{c}^*rho state with a mass about 3187–3188 MeV.