Coupling of dipole mode to gamma-unstable quadrupole oscillations

The coupling of the high-lying dipole mode to the low-lying quadrupole mode s for the case of deformed gamma -unstable nuclei is studied. Results from the geometrical model are compared to those obtained within the dipole boso n model. Consistent results are obtained in both models. The dipole boson m odel is treated within the intrinsic frame, with subsequent projection onto the laboratory frame. As an application, calculations of photonuclear cros s sections in gamma -unstable nuclei are presented. (C) 2001 Elsevier Scien ce B.V. All rights reserved.