Pion Absorption on the Diproton

A partial-wave analysis of recent low-energy pion-absorption data on a diproton (${}_{}{}^1{}_{}{}^{}S_0^{}{}_{}{}^{}$) in ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ is supplemented by proton-neutron final-state-interaction phase shifts and mixing parameters, yielding a model-independent determination of the absorption amplitude. Several possible amplitudes describe the existing angular distribution, but these can essentially be distinguished by a polarization measurement.