Abstract. High-spin states in 176Ir have been investigated via the 149Sm (31P, 4nγ) 176Ir reaction through excitation functions, X-γ and γ-γ coincidence measurements. Four rotational bands have been identified for the first time and their configurations are suggested on the basis of the existing knowledge of band structures in odd-odd nuclei as well as the measured in-band B(M1)/B(E2) ratios. Among the four bands observed, the πh9/2⊗νi13/2 and πi13/2⊗νi13/2 bands exhibit an anomalous signature splitting. The signature inversion point is observed in the former at Ic=18 which is consistent with expectations; this signature inversion spin in the πi13/2⊗νi13/2 band may be larger than 25. The combined effects of Coriolis and p-n residual interactions involved in such an inversion phenomenon have been discussed qualitatively.

High-spin states in doubly odd 170Re have been populated via the 142Nd(32S, p3nγ) reaction at beam energies of 155 and 166 MeV. K X-γ and γ-γ coincidences have been measured using a detector array consisting of 12 high-purity germanium detectors with BGO suppressors. A rotational band is identified and assigned to 170Re for the first time. This band is proposed to be built on the πh11/2⊗νi13/2 two-quasiparticle configuration by comparing the band properties with known bands in neighboring nuclei and the cranked-shell model calculations.

The low- and medium-spin states of the N=50 neutron-rich, 37 87Rb, 35 85Br, 34 84Se and 32 82Ge isotones have been populated in deep-inelastic processes produced by the interaction of 460 MeV 82Se ions with a 192Os target. The subsequent g decay has been investigated at the Laboratori Nazionali di Legnaro using the GASP g-ray detector array. The comparison of the experimentally observed excited states with shell-model calculations performed with and without neutron degrees of freedom has allowed the investigation of the role of the neutron-core breaking excitations and therefore of the N=50 shell gap. The inclusion of neutron configurations in the shell-model calculations results in an improved agreement between the experimental and calculated level energies at medium and high spin. These results highlight the considerable contribution of neutron-core particle-hole excitations across the N=50 shell gap to the level configurations. The overall agreement of the measured excited states with the shell-model predictions is indicative of the persistence of the N=50 shell gap down to Z=32.

High spin states in 174Re have been investigated via the 152Sm (27Al, 5nγ) 174Re reaction. Gamma-ray excitation functions, x-γ and γ-γ coincidences have been measured. Two rotational bands built on the πh9=2⊗νi13=2 and πh11=2⊗νi13=2 con gurations have been identi ed and extended up to high-spin states. The relative spin and parity of the band levels have been unambiguously xed due to observations of several inter-band transitions. Both the bands show the low-spin signature inversion, which is consistent with systematic expectations for the high-j two-quasiparticle bands in the A=170 mass region.

High-spin states in 179Au have been studied experimentally using the 149Sm (35Cl,5n) fusion-evaporation reaction at beam energies of 164−180 MeV. A rotational band built on the 1/2[660](i13/2) Nilsson orbital has been established for 179Au. Properties of the 1/2 [660](i13/2) bands in the odd-A Au nuclei are discussed with an emphasis on the evolution of bandhead energy and deformation while changing neutron number.