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

The structure of neutron-rich light nuclei around N = 20, 28 and 40 has bee n investigated at GANIL by means of in-beam gamma spectroscopy using both s table and radioactive beams. The neutron-rich Ni-66,Ni-68 have been produce d from the fragmentation of a primary Zn-70 beam with a Ni target. Their re duced transition probabilities B(E2) from the 0(+) ground state to the firs t 2(+) state have been extracted from Coulomb excitation cross-section meas urement. Some of the obtained results related to the effectiveness of the N = 40 spherical sub-shell closure are discussed. In-beam gamma -spectroscop y 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 stat es has been measured for the first time in nuclei around Mg-32 and S-44. Le vel schemes are proposed and discussed for a large number of these neutron- rich nuclei around N = 20 and N = 28.