Abstract
A recently proposed model (MM) of higher baryon couplings for and mesons is reformulated by reviewing the fuller possibilities of the "recoil term" in the primitive quark-meson interaction. While this introduces no basic change in the -meson coupling structures, it yields an entirely new ()-wave coupling of mesons to baryons, which is capable of generating helicity-flip amplitudes. The advantage of this new coupling structure over the earlier one is demonstrated through the excellent reproduction of (i) the angular distribution in decay and (ii) the appreciable magnitudes as well as energy variations of the asymmetry parameter in pion photoproduction. In addition to a comparison of the two coupling structures (old and new), the present paper is also designed to study the role of still another parametric structure for the form factor - one which exhibits better convergence properties at higher energies than those discussed in MM. The additional processes studied in this connection are (i) and photoproduction at intermediate energies (> 2 GeV), (ii) polarization of the recoil proton in and photoproduction, and (iii) photoproduction at high energies (∼ 6 GeV), in accordance with our earlier scheme of -channel resonances. In connection with photoproduction the roles of some pertinent resonances such as , , and are discussed, especially in relation to supermultiplet assignments.
- Received 12 April 1971
DOI:https://doi.org/10.1103/PhysRevD.4.1409
©1971 American Physical Society