Abstract. High-spin states in 143Pm have been investigatedvia the 128Te(19F,4nγ)143Pm reaction using techniques of in-beam γ-spectroscopy. γ-ray singles, γ-γ coincidences, γ-ray anisotropies andDCO ratios have been measured. Based on these measurements, the level scheme of 143Pm has been extended up to an excitation energy of 10535.4 keV, including 48 new γ-rays deexciting 28 new levels. The yrast levels in 143Pm can be understood qualitatively in the framework of a weak-coupling model.

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 the odd-odd 182Au nucleus have been investigated using the 152Sm (35Cl, 5nγ)182Au reaction through X-γ and γ-γ-t coincidence measurements. Rotational bands based on the πh9/2⊗νi13/2 and πi13/2⊗νi13/2 configurations have been identified. It is found that the two bands show characteristics of low-spin signature inversion. The observed signature inversion can be well reproduced by pairing-deformation self-consistent cranking Woods-Saxon calculations.

The high-spin states of 157Yb have been studied via the 144Sm(16O, 3n) reaction at 16O energy of 90 MeV using techniques of in-beam γ-ray spectroscopy. Measurement of γ-γ-t coincidences was performed with 11 BGO (AC) HPGe detectors. Based on the measured results of γ-γ coincidences, γ-ray anisotropies and DCO ratios, the level scheme for 157Yb was established. The shape co-existence and structural evolution of the νi13/2 band with increasing angular momentum in 157Yb have been discussed. The systematics of the νi13/2 bands in the N=87 odd-A isotones have been compared.

The soarch for the πi13/2⊗νi13/2 band in 178Ir has been conducted through the 152Sm (31P, 5nγ)178Ir reaction and thc excitation functions，x-γ and γ-γ-t coincidence mcasurements. Five rotational bands have been nowly identified The low-spin signaturc inversion in the πi13/2⊗νi13/2 band has been confirmed by the observations of linking transitions and signaturc crossing at I=25.5h. The inversion phenonJenon in πh11/2⊗νi13/2, rcho/2⊗νi13/2 and πi13/2⊗νi13/2 structulcs in 178Ir provides a unique testing ground for diffbrent theorctical interpretations.