Near Yrast Study Of The Fpg Shell Nuclei Ni-58, Cu-61, And Zn-61

The medium spin, near yrast states of the fpg shell nuclei Ni-58, Cu-61, and Zn-61 have been studied following the fusion evaporation of a Mg-24 beam and a Ca-40 target. Discrete transitions were unambiguously identified using the AYEBALL gamma-ray array in conjunction with the Argonne fragment mass analyzer and a split anode ionization chamber. The decay schemes of Ni-58(28), Cu-61(29), and Zn-61(30) have been extended with the results of gamma-gamma coincidences and directional correlation from oriented state measurements used to determine the level excitation energies, spins, and parities of a number of near yrast states. The decay schemes deduced are compared with previous work and interpreted in terms of shell model calculations, with a restricted basis of the f(5/2), p(3/2), p(1/2) orbitals outside a Ni-58(28) core, and either the g(9/2) orbital with a closed core, or f(7/2) excitations from the core. [S0556-2813(99)01112-7].