Excitation and decay of electric giant resonances — especially the isoscalar giant monopole resonance

Abstract

In this paper recent progress in the excitation and decay of electric giant resonances, especially the isoscalar giant monopole resonance will be discussed. The compressibility of nuclear matter Kn.m. will be determined from the newest experimental data on the GMR over the mass range 24 < A < 208 using a semiphenomenological expression for the nuclear compressibility KA in terms of a volume, surface, asymmetry and Coulomb contribution. The resulting value, Kn.m. ∼ 260 Mev is in good agreement with nuclear matter calculations. Recently new data for the neutron decay of the GMR in 208Pb and 124Sn have been obtained. These data turn out to be compatible with a nearly 100% statistical decay mode if in the statistical model calculations a realistic level scheme for the residual nuclei is used. A similar analysis applied to existing data on the GDR in 208Pb shows that also for this resonance the data are compatible with a nearly 100% statistical decay mode.