Selection rules and quark correlations in the N resonance spectrum
نویسندگان
چکیده
A “Λ selection rule” for N∗ resonances in the presence of QCD mixing effects is identified. Due to the QCD mixing, excitations of 20-plets are possible in SU(6). We show that this selection rule is useful for classifying PDG states at N = 2, and for clarifying whether strongly correlated diquarks survive for
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