Nuclear structure of Ge74 from inelastic neutron scattering measurements and shell-model calculations

The low-lying, low-spin levels of ⁷⁴Ge were studied with the (n,n^'γ) reaction. γ-ray excitation function measurements were performed at incident neutron energies from 1.6 to 3.8 MeV, and γ-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, γ-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.