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The structure of hadronic transition amplitudes h→h′+h″ via quark triangle loops is investigated in terms of hadron quark vertex functions [Formula: see text], using for illustration the case of the ρ→ππ transition. A Bethe-Salpeter model based on the Covariant-Instantaneity-Ansatz (CIA) for its kernel which provides an exact interconnection between the 3D and 4D forms the BS wave function, determines the structure [Formula: see text]. The nonlocality feature inherent in the vertex function causes the imaginary part of gρππ calculated from the loop integral to be generally different from its dispersion relation value which would be obtained from analyticity of gρππ in the ρ-mass. Pending a proper understanding of this nonlocality (associated with confining interactions) only the real part of gρππ is found unambiguous while the imaginary part is model-dependent.

The unequal-quark-mass problem of excited A and Z states is treated through a multichannel generalization of a relativistic Bethe-Salpeter treatment of the simpler (equalmass) problem of N and A as well as meson states recently found to give excellent fits to the corresponding spectra. The present fits to the A and B masses are fully in tune with the quality of the NL and AL results, as evidenced by the highly consistent values of the appropriate universal function F ( M ) representing the central (masd2 for each N supermultiplet, calculated with the same reduced spring constant and quark masses as employed earlier for N L , AL, and meson states. These F ( M ) values now include the onegluon-exchange corrections which help in improving the F ( M ) regularities over the pure harmonic-oscillator prediction. The F ( M ) representation also brings out rather succinctly a modest symmetry-breaking trend ( -5 -10 % ) at the collective supermultiplet level with little scatter among individual members.