LABORATORI NAZIONALI DI LEGNARO
An interesting aspect of nuclear structure is the shell evolution for isotopes with extreme isospin values. Experimental evidence suggests the disappearance of the shell closure at N=8, N=20 and N=28 in various neutron-rich isotopes as well as the appearance of new magic neutron numbers at N=16 for 24O, and at N= 32 and N=34 for Ca isotopes. Shell evolution originates in the properties of the in-medium nucleon-nucleon interaction and the 3N forces coming from the composite structure of the nucleons. In this sense, the spectroscopy of the first excited state of nuclei near closed shells, where minimal effects of correlations such as pairing or deformation are present, offers a first insight into the evolution of shell structure. The SEASTAR project, carried out at the Radioactive Isotope Beam Factory (RIBF), operated by the RIKEN Nishina Center and the Center for Nuclear Study, aimed at a systematic search for 2+ excitation energies, E(2+), from 52Ar to 110Zr. In this talk, an overview of the SEASTAR project will be presented, with particular focus on the case of shell evolution in N=40 isotones.

DATA: 14-12-2018