Self-energy of theΔresonance in finite nuclei and Fermi broadening

Abstract
It is shown that because of the Fermi motion of the target nucleons the Δ resonance exhibits a large kinematic broadening in nuclei. This broadening is unrelated to the coupling of the isobar to inelastic channels and is neglected in some of the calculations of pion-nucleus scattering based upon the isobar-hole model.