Dynamical study of D^*DK and D^*D D systems at quark level

Inspired by that Belle2 Collaboration recently reported T₂₂, which can be interpreted as a molecular DD^*, we investigated the trihadron system of T₂₂ partner with IJ^P=01^- in the framework of a chiral quark model. It's widely accepted that the main component of X (3872) contains the molecular DD^*, while the main component of Dₒ₀^* (2317) is molecular DK. Based on these three well-known exotic states, T₂₂ (DD^*), X (3872) (DD^*) and Dₒ₀^* (2317) (DK), we dynamically investigate D^*DK and DD^*D systems at quark level to search for possible bound states. The results show that both of them are bound states, in which the binding energy of the molecular state DD^*K is relatively small, only 0. 8 MeV, while the binding energy of DD^*D is up to 1. 9 MeV. According to the calculation results of the Root-square-mean distances, the spatial structure of the two systems shows obvious (DD^*) - (D/K) structure, in which D is close to D^* while DD^* as a whole is relatively distant from the third hadron (D/K), which are similar to the nucleon-electron structure. As a result, we strongly recommend that these bound states DD^*D and DD^*K are searched for experimentally.