Separable potential analysis of coupledNN−NΔscattering

A simple coupled channel separable potential model is used to fit the $J^p=2^{+} \mathrm{and} 3^{-}$ $\mathrm{NN}$ amplitudes. Analytic structure of the resulting amplitudes is studied with emphasis on the location of poles which may represent dibaryon resonances. The study shows that there exists a wide range of potential models which describe the observed rapid energy dependence in the amplitudes in terms of threshold effects with an absence of resonance poles.