Rotational Behavior at High Spin inHf168

Abstract

The yrast sequence in ${}_{}{}^{168}{}_{}{}^{}\mathrm{Hf}$ has been extended to $I^{\pi }={34}^{+}$ and two negative-parity side-bands have been observed to $I^{\pi }={33}^{-} \mathrm{and} {30}^{-}$. At high rotational frequencies all three bands have little spin alignment and have moments of inertia which remain constant as a function of frequency. Possible evidence for the vanishing of pairing correlations is discussed.