The (p,π−) reaction and Δ++ components of nuclei

The use of the (p, π^?) reaction as a probe to determine Δ⁺⁺(1232) components of nuclear wave functions is examined within the framework of a model which treats baryon resonances on the same footing as nucleons. Nuclear structure properties which affect the Δ -probability are discussed. Estimates of cross sections, at several energies, are made for the Δ⁺⁺ transfer contribution as well as for the competing processes: proton charge exchange (p, n) followed by an (n, π^?) reaction; emission of a π⁰ followed by pion charge exchange (π^?, π⁰) . Even with Δ-probabilities as small as 0.0001 the Δ-transfer process can compete with ordinary background charge-exchange reactions.