Magnetic moments of N = 48-50 nuclei and proton core polarization

Reports a systematic study of g-factors in isomeric states characterized by a closed neutron shell (N = 50) and a varying number of valence shell protons. The excitation energies and gamma decay properties of these isomers are well described by the shell model calculations of Gloeckner and Serduke (1974) which assume a closed 88Sr core with protons actively distributed in the 2psub(1/2) and 1gsub(9/2) proton orbitals. The experiments show significant breakdowns of the additivity rule of the nuclear shell model. It is demonstrated that the observed g-factor differences are caused by the dependence of the core polarization on the occupancy of the proton valence shells. In a second series of experiments the authors have measured g-factor of isomeric states in N = 48, 49 nuclei. (Auth.)