Lifetimes of high-spin states in the [Formula Presented] band of [Formula Presented]Re

Lifetime measurements on the [Formula Presented] band built on the proton configuration [Formula Presented] in [Formula Presented] have been carried out by the Doppler-broadened line shape method with the use of the GAMMASPHERE array in an early-implementation arrangement. Lifetimes of the stretched [Formula Presented] transitions from states of spin [Formula Presented] in this band were measured, and the transition quadrupole moments calculated from these lifetimes are consistent (average [Formula Presented] with a large and near-constant deformation [Formula Presented] over the frequency range of [Formula Presented]–0.47 MeV. This result attests to the strong deformation-driving effect of the intruder [Formula Presented] orbital when it lies just above the Fermi surface. From thin-target measurements, it was possible to add three new levels to this band and to determine that the experimental aligned angular momenta gradually evolve over a large frequency range and level off with a total gain characteristic of alignment by [Formula Presented] neutrons. Calculations carried out for diabatic configurations give a satisfactory accounting of the alignment gain. However, because of the large interaction between crossing bands, a more meaningful description of the deformation pattern in this band was achieved through calculations of the spin-adiabatic type. Both calculations are discussed and compared with the experimental results.