Pygmy Dipol Resonances as a Manifestation of the Structure of the Neutron-Rich Nuclei

Abstract

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.

8 pages, 3 figures, Proceedings of the International Conference on Collective Motion in Nuclei Under Extreme Conditions (COMEX1), Paris, France, 10-13 June 2003

References in corpus (1)

• Concentration of electric dipole strength below the neutron separation energy in N = 82 nuclei

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• Evolution of the pygmy dipole resonance in nuclei with neutron excess
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