Ultra-fast timing study of exotic neutron-rich Fe isotopes

Abstract

The cornerstone of nuclear structure, as we know it from stable nuclei, is the existence of magic numbers. The most stable nuclei arise for completely occupied shells, closed shells, and give rise to the magic numbers. At the Valley of Stability their values are 8, 20, 28, 50, 82 and 126. The steady development of the production, separation and identication of exotic nuclei, together with the improvement of the detection techniques, makes it possible to experimentally explore nuclei further away from the Valley of Stability. These exotic nuclei with nucleon numbers supposed to be magic do not always have the properties one would expect. As extra nucleons are added (or removed) from stable nuclei, the single particle energies are modied and strong quadrupole correlations appear, which may neutralize the spherical meanfield shell gaps. The investigation of the evolution of shell structure far from stability has become a major subject in Nuclear Physics. Research in this field has strong implications also in nuclear astrophysics, because exotic nuclei have a crucial role in the processes of stellar nucleosynthesis leading to the formation of the nuclei present in the Universe. The IS474 experiment was performed at the ISOLDE facility, CERN, where $^{59-66}$Mn isotopes were created and their $\beta$-decay chains studied. In this PhD Thesis we focused on the study of the neutron-rich iron isotopes (odd-A $^{63;65}$Fe and even-A $^{66}$Fe) by means of gamma and Advanced Time-Delayed spectroscopy