A dipole component in the Yrast cascade and its possible interpretation

Quasi-continuum γ-rays following heavy ion, xn reactions have been studied for the prolate final nuclei 161Yb, 174,175W. The effect of the discrete lines arising from the groundstate bands and other bands have been subtracted out so that the lower energy part of the continuum can be properly observed. This has revealed the presence of a low energy component with strong negative anisotropy, suggesting a dipole component in the yrast cascade. A simple model resulting in such a component is considered an discussed. Some comments are made regarding the interpretation of moments of inertia derived from continuum spectra