Evidence for dibaryon resonances from the measurement of the tensor polarization t20 in π+−d scattering

The tensor polarization t20 of π+−d elastic scattering has been measured at 117 MeV, 134 MeV, 142 MeV and 151 MeV as a function of scattering angle. While at 134 MeV a strong and oscillatory behaviour prevails over the angular range measured (100−180° c.m.), a considerable flattening of this structure is observed at 117 MeV and 151 MeV. This energy dependence and other observations are believed to manifest evidence for the presence of nonconventional dynamics in this energy region.