First use of post-accelerated isomeric beams for coulomb excitation studies of odd-odd nuclei around N=40

We report on the first use of post-accelerated radioactive isomeric beams. Long-lived isomeric states in 68Cu and 70Cu have been produced and separated at ISOLDE, CERN. Subsequently they were post-accelerated to 2.86 MeV/u and sent to a target in the center of the MINIBALL spectrometer, used for the detection of the γ-rays of interest. The preliminary results from the Coulomb excitation of the Iπ = 6-, 1 + states in 68Cu and the Iπ = 6- one in 70Cu, compared to a large-scale shell model calculations, hint the importance of the excitations across the Z = 28 gap for the understanding of the nuclear structure in the neutron-rich N = 40 region. © World Scientific Publishing Company.