Theoretical description of giant resonances in stable and unstable magic nuclei

A microscopic approach based on the consistent use of the Green function method has been developed and applied for description of giant resonances in magic stable and unstable nuclei. The approach takes into account, in addition to the RPA configurations, more complex 1p1hxphonon configurations and the single particle continuum. A reasonable agreement with the available experimental data has been obtained, especially for the integral characteristics, including giant resonance widths. An indication for the explanation of the fine structure due to 1p1hxphonon configurations has been also obtained for the isoscalar E2 resonance in 208Pb. Due to the consistent treatment of 1p1hxphonon ground state correlations additional isoscalar E0 strength in 208Pb for the (6-12) MeV interval and in 40Ca for the (7-14) MeV interval has been found. New features for E1 and M1 resonances are found in the ''very exotic'' 78Ni and 100Sn nuclei. (orig.)