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The odd-odd 88 37Rb51 and 86 35O$ + $51 nuclei have been produced as fission fragments in the fusion reaction 18O$ + $208Pb at 85MeV bombarding energy and studied with the Euroball IV array. Their high-spin level schemes have been built from the triple $ \gamma$ -ray coincidence data and $ \gamma$ - $ \gamma$ angular correlations have been analyzed in order to assign spin and parity values to many observed states. The proposed configurations involve proton excitations from three sub-shells located close to the Fermi levels, $ \pi$ p3/2 , $ \pi$ f5/2 , and $ \pi$ g9/2 , the $ \nu$ d5/2 neutron acting as a spectator. The residual $ \pi$ $ \nu$ interactions are extracted from the multiplets of states resulting from the $ \pi$ p3/2 $ \nu$ d5/2 and $ \pi$ f5/2 $ \nu$ d5/2 configurations. The empirical values of the latter are discussed and compared to those known in two similar configurations having jp = jn with lp = ln + 1 , where the role of the tensor force had been highlighted. [ABSTRACT FROM AUTHOR]

The 81, 82, 83, 85Se nuclei have been produced as fission fragments in the fusion reaction 18O + 208Pb at 85MeV bombarding energy and studied with the Euroball IV array. Their high-spin level schemes have been built from the triple $ \gamma$ -ray coincidence data and $ \gamma$ - $ \gamma$ angular correlations have been analyzed in order to assign spin and parity values to many observed states. The lowest-spin states of the two-neutron and three-neutron configurations are strongly mixed with two-proton excitations among the fp orbits. On the other hand, the highest-spin states of these neutron configurations are found to remain almost pure. Neutron excitation across the N = 50 gap is observed both in 83Se49 and in 85Se51 . [ABSTRACT FROM AUTHOR]