DEFORMATION AND SIGNATURE SPLITTING IN BR-74

The high-spin states of Br-74 were studied via the Ti-48(S-32,alpha-pn)Br-74 and the Ni-58(F-19,2pn)Br-74 fusion-evaporation reactions at energies of 105 and 62 MeV, respectively, using the Florida State University Tandem LINAC. gamma-gamma coincidence arrays were produced using four Compton-suppressed Ge detectors. Two independent groups of gamma rays were studied - one of positive parity and one of negative parity, both of which appear to be based on an isomeric 4(+) state. Lifetimes were measured using both the Doppler-shift attenuation and recoil-distance methods. A cranking-model analysis of the bands shows that the kinematic and dynamic moments of inertia for the bands are rather similar and fairly constant for high spins with values of (20-23)h2/MeV. A phase reversal occurs in the signature splitting in the yrast band around spin 9 which is related to the quasiparticle alignments. The lifetimes imply an average axial quadrupole deformation of 0.37 in the yrast band and 0.34 in the negative-parity band. These deformations are close to those predicted by Hartree-Fock-Bogolyubov cranking calculations.