THE METHOD OF TIME-ORDERED GRAPH DECOUPLING AND ITS APPLICATION TO THE DESCRIPTION OF GIANT-RESONANCES IN MAGIC NUCLEI

A microscopic approach to analyzing the excited states of magic nuclei is described. It is based on the systematic use of the method of quan tum Green functions. When applied to the theory of giant multipole res onances, the approach explicitly includes the three principle mechanis ms of resonance formation in a finite nucleus: decay via particle-hole configurations of the discrete spectrum, decay via particle-hole conf igurations with a particle in the continuum, and decay via more compli cated configurations of the particle-holeXophonon type. The results of a numerical realization of this approach for describing giant resonan ces in magic stable and unstable nuclei are discussed. (C) 1997 Americ an Institute of Physics.