Measurement of the Reaction π+n↑ → π+π-p at 5.98 and 11.85 GeV/c using a Transversely Polarized Deuteron Target

In an experiment carried out at the CERN-PS the reaction π+n ↑ → π+π-p has been studied using the CERN polarized deuteron target. Assuming that only S- and P-waves contribute to the angular distribution for dipion masses ≲ 1 GeV, the experiment yields 14 linearly independent observables which allow model independent amplitude analysis. The experiment contributes new information on the energy dependence and also on the mass-dependence of dipion production at |t| ≳ 0.3 where natural exchange is found to dominate.