Nuclear rotation at high angular velocities

Deformed nuclei rotating with very high angular velocities reveal many interesting properties of the strongly interacting quantal many-body system. Highly excited collective states are preferentially populated in heavy ion induced reactions. In many nucleides a gradual increase of the moment of inertia with the angular velocity has been established. However, in some deformed nucleides a drastic behaviour of thr moment of inertia at spin-values around 12–16 $\text{h}\text{?}$ has been experimentally well confirmed. This review aims not only to present the experimental results but also to discuss representative theoretical approaches to explain the observed behaviour.