Speaker
Description
The BESIII Collaboration recently observed a new charmonium-like vector state Y(3872) in e^+e^-\rightarrow D\bar{D}^, which should be the first P-wave D\bar{D}^ molecular resonance. The experimental and theoretical identification of the P-wave dimeson state holds paramount importance in enhancing our comprehension of the non-perturbative QCD and few-body physics. Its existence is firmly established in a unified meson-exchange model which simultaneously depicts the features of the \chi_{c1}(3872), Z_c(3900) and T_{cc}(3875). This scenario can be directly examined in the e^+e^-\rightarrow D\bar{D}^/\bar{D}D^ cross section to see whether a resonance exists at the threshold. The credibility of the investigations is also ensured by the fact that the P-wave interaction dominantly arises from the well-known long-range pion exchange. Additionally, the existence of the P-wave resonance only depends on the interaction strength and is less sensitive to the potential shapes. We extensively calculate all systems up to P-wave with various quantum numbers and predict a dense population of the D\bar{D}^/\bar{D}{D}^ and DD^ states, where the S-wave D\bar{D}^/\bar{D}{D}^ state with I^G (J^{PC})=0^- (1^{+-}), P-wave $D\bar{D}^/\bar{D}{D}^ state with I^G(J^{PC})=0^+(0^{-+}), and P-wave DD^ state with I(J^P)=0(0^-) are more likely to be observed in experiments.
