Tensor Polarization inπ−dScattering and Pion Absorption

Angular distributions of the deuteron tensor polarization, $t_{20}$, in $\pi -d$ elastic scattering at pion energies of 180, 220, and 256 MeV and an excitation function at ${{\theta }_{\mathrm{c}.\mathrm{m}.\mathrm{}}}^{\pi }\approx 144°$ have been measured. The results suggest that all published calculations fail to include true pion absorption properly in the treatment of the $\pi \mathrm{NN}$ system. No rapid angular or energy dependence was found near pion energies of either 134 or 256 MeV, where other experiments have suggested the existence of dibaryons.