Evidence for Hyperdeformation in ${}_{}{}^{147}{}_{}{}^{}Gd$

A pair of rotational bands with 9 and 11 discrete $\gamma$ rays with a regular spacing of about 29 keV extending from 1016 to 1340 keV have been identified as belonging to ${}^{147}\mathrm{Gd}$. Evidence from their population, decay characteristics, very large dynamic moments of inertia of ${\Im }^{\left(2\right)}=140\mathrm{}$ ${ħ}^2{\mathrm{MeV}}^{-1\mathrm{}}$, and agreement with theoretical predictions support the hyperdeformed character of these bands. These band structures correspond to a spheroid with major-to-minor axis ratio of about 3:1.