Spectroscopy of 161Hf from low to high spin.

Excited states in the neutron-deficient nucleus 72161Hf89 have been populated using the 118Sn(48Ti,5n) 161Hf and 110Pd(56Fe,5n) 161Hf fusion-evaporation reactions at 240 and 270 MeV, respectively. The level scheme for 161Hf has been extended with the observation of new band structures and an Iπ = (13/2+) isomeric state with a half-life of 4.8(2) μs has been identified. The decay path from this isomer to the (7/2-) ground state is established. The yrast band, based on the (13/2+) isomeric state, is extended up to (73/2+) and side band structures are identified up to (69/2-) and (55/2-). Quasiparticle assignments for these rotational structures are made on the basis of their alignment properties and Woods-Saxon cranked shell-model calculations. [ABSTRACT FROM AUTHOR]