Search for highly excited states in ²⁸Si

Abstract

The theoretical and experimental determination of superdeformed states in nuclei in the mass region A≤40 has been since a long time one of the major challenges of nuclear structure studies. Despite the considerable experimental and theoretical work dedicated to this topic, up to now superdeformed bands have been found in only two nuclei, ³⁶Ar and ⁴⁰Ca. While the experimental signature of the superdeformed nature of those states is irrefutable, their theoretical interpretation is still uncertain. In particular, it is not clear whether clusterisation is responsible of the onset of superdeformation. For this reason, we wanted to investigate an even lighter system, ²⁸Si, where a number of theoretical calculations predict the presence of superdeformation as an effect of the cluster structure of the nucleus.