v 1 1 8 A ug 1 99 5 Quark Model Explanation of the N ∗ → Nη Branching Ratios
نویسنده
چکیده
The constituent quark model can explain the strong selectivity of the Nη decay branching ratios of the nucleon resonances if the fine structure interaction between the constituent quarks is described in terms of Goldstone boson exchange. This chiral quark model predicts that the S wavefunctions in lowest order, should have large Nη branching ratios, while Nη decay of the other resonances that have different flavor-spin symmetry should be strongly suppressed in agreement with the experimental branching ratios.
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