A local derivative coupling model is used to study theφ′→ππ and other dipionic decays ofφ andφ″, as an alternative to theε-model. The results obtained are quite satisfactory. We findt hat the existence of theε-resonance is not essential in order to understand the dipionic decays of the psions at the present level of experimental data available.

The four-body dynamical equations for two distinct pairs of identical particles derived earlier are applied to investigate the system$${}_{\Lambda \Lambda }^{10} Be$$. The two-body potentials have been taken to be of the Yamaguchi form, and the Bateman approximation has been used for the other amplitudes. From the set of coupled integral equations, the separation energy, B_ΛΛ, for the two Λ particles in$${}_{\Lambda \Lambda }^{10} Be$$ is obtained as 43·97 MeV.

Weinberg’s spectral function sum rules are examined to study the axial vector mass spectrum at the level of SU(4). New mass relations and general mass constraints are derived to predict the masses of the charmed axial vector mesons and theI=0 pseudoscalar decay constants.