0+,T=0(p,p')0-,T=1 pion like excitations and nuclear response in the spin-isospin channel

We discuss the importance of the JP=0+,T=0→JP=0-,T=1 pionlike excitation in 40Ca, comparing it with results for smaller nuclei. Spin-isospin strength distribution effects due to high-lying nucleon-hole and Δ-hole excitations combined with the Landau-Migdal residual interaction are studied in an exact finite-nucleus calculation. We also present a comparison with a Fermi gas calculation in the local density approximation. We find important renormalization effects including interesting enhancement and quenching for different regions of the momentum transfer, which may be relevant and useful in explaining available experimental results for light nuclei. We demonstrate that studies on heavier nuclei will give complementary information on the diamesic renormalization and finite-system effects in the spin-isospin mode that is not available in the case of smaller nuclei