Low-lying dipole excitations in the transitionalnuclei190,192Os

Abstract

Photon scattering experiments have been performed on the nuclei ${}^{190,192}\mathrm{Os}$ in order to investigate low-lying dipole excitations in the energy range ${E}_{\ensuremath{\gamma}}<4 \mathrm{MeV}$ in nuclei which are transitional between well-deformed rotors and $\ensuremath{\gamma}$-soft nuclei. We determined excitation energies, spins, and absolute photon scattering cross sections. The low-lying dipole strength in these even-even nuclei is highly fragmented.