Projectile ∆ and target - Roper excitation in the p ( d , d ′ ) X reaction

In this paper we compare a model that contains the mechanisms of ∆ excitation in the projectile and Roper excitation in the target with experimental data from two (d, d ′) experiments on a proton target. The agreement of the theory with the experiment is fair for the data taken at T d = 2.3 GeV. The ∆ excitation in the projectile is predicted close to the observed energy with the correct width. The theory, however, un-derpredicts by about 40% the cross sections measured at T d = 1.6 GeV at angles where the cross section has fallen by about two orders of magnitude. The analysis done here allows to extract an approximate strength for the excitation of the Roper [N * (1440)] excitation and a qualitative agreement with the theoretical predictions is also found.