Inelastic thresholds and dibaryon resonances

A method of Basdevant and Berger is applied to the problem of whether there are $\mathrm{pp}$ resonances near the $n{\Delta }^{++}$ threshold. In particular, the ${}_{}{}^1{}_{}{}^{}D_2^{}{}_{}{}^{}$ partial wave of proton-proton elastic scattering is analyzed around this threshold. The method is expected to determine (in principle) whether the $\mathrm{pp}$ partial waves in which structure has been observed are resonant and, in this event, allow a reliable determination of the resonance parameters.