Light Four-quark States and New Observations by BES
نویسندگان
چکیده
Four-quark states are discussed within the constituent quark model. Incompleteness of existed studies of four-quark state with QCD sum rule is analyzed. The masses of diquark cluster were determined by QCD sum rules, and light four-quark states masses were obtained in terms of the diquark. The four-quark state possibility of the newly observed near-threshold pp̄ enhancement, X(1835), X(1812) and X(1576) by BES is discussed.
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