Nuclear structure of 74Ge from inelastic neutron scattering measurements and shell-model calculations

The low-lying, low -spin levels of 74 Ge were studied with the ( n , n ' gamma ) reaction. gamma -ray excitation function measurements were performed at incident neutron energies from 1.6 to 3.8 MeV, and gamma -ray angular distributions were measured at neutron energies of 2.0, 2.6, 3.0, 3.4, and 3.8 MeV. From these measurements, level spins, level lifetimes, gamma -ray branching ratios, and multipole mixing ratios were determined, and a comprehensive level scheme approaching 3 MeV in excitation energy is presented. Low-lying collective band structures are identified, and a comparison of the level characteristics with large-scale shell -model calculations yields excellent agreement.