Exotic Nuclei – A Challenge for Nuclear Structure Models
Nuclei are interesting objects in several respects: They are prototypes of finite Fermion systems with pronounced quantum effects, they constitute an extremely demanding test case for many-body theory, they are key ingredients in astrophysical modeling, and there are widespread applications as probes for analysis, e.g., in materials science or medicine. Thus there are worldwide many activities to provide new information, particularly on nuclei far off the valley of stability. These new data help enormously to scrutinize the predictive power of the various nuclear structure models and to improve on hitherto vaguely fixed aspects. The talk will concentrate particularly on the performance of self-consistent mean-field models.
A brief introduction of self-consistent nuclear models will be given taking the Skyrme forces as example and sketching the links to density functional theory. After that short formal introduction, we concentrate on the practical side, namely the ability of the models to describe nuclear data for ground states and low-energy excitations. We will see at many places how data from exotic nuclei call in question existing models or parameterizations thereof. This is demonstrated on several examples where the mismatch has led to a deeper understanding of the mechanisms and improvement of the mean-field models. This, in turn, provides more reliable extrapolations to nuclides which are of astrophysical interest. There are other cases where one needs to go beyond a pure mean-field treatment by considering collective vibrations of nuclei which, in turn, also provides low energy spectra as further benchmark.