Nuclear-structure studies of rotating nuclei

The yrast spectroscopy at high-spin in nuclei has been extensively developed for the last ten years, both experimentally and theoretically. Progress has been achieved in the understanding of the nuclear structure at high-spin, especially in terms of quasiparticle motion in rotating potentials. There are at present two ways of populating nuclear high-spin states, namely Coulomb excitations and (HI,xn) reactions. By means of Coulomb excitations one can reach, for the moment, states with spin I≤32. Thus, the quantitative information on the yrast spectroscopy of high-spin states comes from the analysis of discrete γ-rays emitted from evaporation residues in (HI,xn) reactions. The highest spin (the highest rotational frequency) obtained in this kind of analysis is at present I≤45. This is certainly the region of spin at which one expects a drastic change of pair-correlations as well as the deviation of the nuclear shape from axial-symmetry