SU(6)Wand Baryon Resonances of Odd Parity

An ${\mathrm{SU}\left(6\right)\mathrm{}}_W$-symmetric dynamical model, used previously to predict quantum numbers and branching ratios of even-parity meson resonances, is extended to odd-parity baryon resonances. It is assumed that meson exchange forces of the tensor type dominate. The relative sizes of the tensor forces in all meson-baryon states are given by the assumed ${\mathrm{SU}\left(6\right)\mathrm{}}_W$ symmetry. The matrix elements of the tensor forces corresponding to the lowest orbital angular momentum in odd-parity states are $S-D$-wave transition elements. Those $S-D$ states in which the largest forces exist are assumed to resonate. $\mathrm{SU}\left(3\right)\mathrm{}$ singlet states of $j=\frac{1}{2} \mathrm{and} \frac{3}{2}$ are predicted; these may be identified with the 1405- and 1520-MeV ${Y_0}^{*}$ particles. The predicted octet resonances correspond to the two distinct $\frac{f}{d}$ ratios 1 and $-\frac{1}{3}$. The predicted results are compared with experimental data on the branching ratios of the 1660- and 1765-MeV ${Y_1}^{*}$ particles, and with the recent measurements of the relative phases of different $\overline{K}N\to \pi \Lambda$ resonant amplitudes by Smart, Kernan, Kalmus, and Ely. Some experiments are suggested that would test the model further.