The QCD sum rule approach is used to analyze the nature of the recently observed new resonance X (4350), which is assumed to be a diquark-antidiquark state [cs][cs] with jPC = 1-+. The interpolating current represe...The QCD sum rule approach is used to analyze the nature of the recently observed new resonance X (4350), which is assumed to be a diquark-antidiquark state [cs][cs] with jPC = 1-+. The interpolating current representing this state is proposed. In the calculation, contributions of operators up to dimension six are included in the operator product expansion (OPE), as well as terms which are linear in the strange quark mass ms. We find ml-+ = (4.82 ~ 0.19) GeV, which is not compatible with the X(4350) structure as a 1-+ tetraquark state. Finally, we also discuss the difference of a four-quark state's mass whether the state's interpolating current has a definite charge conjugation.展开更多
In this paper, I review recent progress in the study of the XYZ particles at Belle. I only focus on studies with charmonium and one or more light mesons in the final states. This covers the X(3872), X(3915), Y(4...In this paper, I review recent progress in the study of the XYZ particles at Belle. I only focus on studies with charmonium and one or more light mesons in the final states. This covers the X(3872), X(3915), Y(4140), X(4350), and the charged Z states.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos.11347174,11275268,11105222,and 11025242
文摘The QCD sum rule approach is used to analyze the nature of the recently observed new resonance X (4350), which is assumed to be a diquark-antidiquark state [cs][cs] with jPC = 1-+. The interpolating current representing this state is proposed. In the calculation, contributions of operators up to dimension six are included in the operator product expansion (OPE), as well as terms which are linear in the strange quark mass ms. We find ml-+ = (4.82 ~ 0.19) GeV, which is not compatible with the X(4350) structure as a 1-+ tetraquark state. Finally, we also discuss the difference of a four-quark state's mass whether the state's interpolating current has a definite charge conjugation.
基金Supported by National Natural Science Foundation of China (10825524,10935008)Department of Energy (DE-FG02-04ER41291) (U Hawaii)
文摘In this paper, I review recent progress in the study of the XYZ particles at Belle. I only focus on studies with charmonium and one or more light mesons in the final states. This covers the X(3872), X(3915), Y(4140), X(4350), and the charged Z states.