Intermediate isobar effects in a two-nucleon mechanism for (p,π)

Publisher Website
Google Scholar
Abstract
Results are presented for a two-nucleon model of the (p,π) reaction in the resonance region. Features of the microscopic two-nucleon model adopted include propagating intermediate pions and rho mesons, and an intermediate delta isobar whose propagator includes interaction with the nuclear system as well as an energy dependent width. Realistic distorted waves are adopted for the external proton and pion. Transitions from a closed shell to two-particle–one-hole and single-particle final states are studied, with both projectile- and target-emission diagrams included, for a carbon target. The results indicate that the effect of finite range delta propagation is important in lowering the sensitivity of the predictions to the details of proton and pion distortions and the bound state wave functions. The results are not very sensitive to the exact nature of the delta-nucleus interaction. The relative magnitude of target-emission or projectile-emission diagrams depends on the particular transition and angle under consideration. Comparison with experiment and future extensions and applications of the model are discussed.