Abstract
Radiative strength functions (RSFs) in have been extracted using the and reactions. The RSFs are U shaped as function of γ energy with a minimum at around . The minimum values increase with neutron number because of the increase in the low-energy tail of the giant electric dipole resonance with nuclear deformation. The unexpected strong increase in strength below , here called soft pole, is established for all isotopes. The soft pole is present at all initial excitation energies in the region.
- Received 26 November 2004
DOI:https://doi.org/10.1103/PhysRevC.71.044307
©2005 American Physical Society