Structure of neutron-rich nuclei around N = 20, 28 and 40 from in-beam gamma-spectroscopy

摘要

Structure of neutron-rich light nuclei around N=20,28 and 40 has been investigated at GANIL by means of in-beam gamma spectroscopy using both stable and radioactive beams. The neutron-rich Ni-66,Ni-68 have been produced from the fragmentation of a primary Zn-70 beam with a Ni target. Their reduced transition probabilities B(E2) from the 0(+) ground state to the first 2(+) state have been extracted from Coulomb excitation cross-section measurement. Some of the obtained results related to the effectiveness of the N=40 spherical sub-shell closure axe discussed. In-beam gamma-spectroscopy using fragmentation reactions of S-36 and Ca-48 beams on a Be target have been recently performed. Gamma-decay of relatively high-lying excited states have been measured for the first time in nuclei around Mg-32 and S-44. Level schemes axe proposed and discussed for a large number of these neutron-rich nuclei around N=20 and N=28. [References: 28]