There is evidence that the highest-spin states observed in nuclei are basically rotational, but that each state emits a distribution of γ-ray energies rather than a single energy. We have measured the width of this distribution and the fraction of the population that emits it, for several (unresolved) γ-ray energy regions in ${}_{}{}^{160}{}_{}{}^{}\mathrm{Er}$. These widths may be related to a damping of the rotational states at the high level densities through which these cascades flow.

• Received 29 July 1985

DOI:https://doi.org/10.1103/PhysRevLett.56.309