Excited Baryon Production and Decays
نویسنده
چکیده
We consider decays of the lowest-lying positive parity (56-plet) and negative parity (70-plet) excited baryons. For the 70-plet, we include both single-quark and two-quark decay operators, and find, somewhat mysteriously, that the twoquark operators are not phenomenologically important. Studies of decays 70 → ∆+γ may strengthen or vitiate this observation. For the 56-plet decays, now using only the single-quark operator, we can predict many strong decays after fitting parameters on the assumption that the Roper is a 3q state. Comparison of these predictions to experiment can verify the structure of the 56-plet. As a sidelight, we show a large Nc derivation of the old Gürsey-Radicati mass formula.
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