Pygmy Dipol Resonances as a Manifestation of the Structure of the Neutron-Rich Nuclei
نویسنده
چکیده
Dipole excitations in neutron-rich nuclei below the neutron threshold are investigated. The method is based on Hartree-Fock-Bogoliubov (HFB) and Quasiparticle-Phonon Model (QPM) theory. Of our special interest are the properties of the low-lying 1 Pygmy Resonance and the two-phonon quadrupole-octupole 1 states in Sn-isotopes including exploratory investigations for the experimentally unknown mass regions. In particular we investigate the evolution of the dipole strength function with the neutron excess. The use of HFB mean-field potentials and s.p. energies is found to provide a reliable extrapolation into the region off stability.
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تاریخ انتشار 2003