Energy dependence of relativistic predictions for pp→dπ in the Δ-resonance region

Abstract

The energy dependence of pp to d pi is calculated for the Delta -resonance range (400<or approximately=Tp<or approximately=800 MeV) extending a preceding relativistic study at Tp=578 MeV. The leading graph is the exchange of a pion and a nucleon. Input are elastic pi N amplitudes (off shell) and relativistic pi NN and dpn vertex functions. Single-neutron exchange is added and distortion factors for the pp and pi d channels are applied. Only moderate sensitivity to variations of the input is found. Comparing with the existing body of data, good agreement is found for the total and differential cross sections. The relative spin observables are reproduced to within 10% of the possible range of variation. The remaining discrepancies can be traced to insufficient strength of pp spin-triplet channels.