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Despite the fact that [sup 208]Pb is probably the best example of a shell model nucleus, little is known about its high-spin states and those of its nearest neighbours, primarily because of the experimental difficulties involved in populating neutron-rich nuclei. The high-spin states formed from the valence orbitals are important since they provide the building blocks from which more complex configurations can be calculated. The same orbitals are involved in particle-octupole vibrational coupling which presumably evolves into octupole deformation in heavier nuclei. In this paper we present the results of recent measurements which have used a range of reaction techniques to access states in the N = 128 isotones, [sup 211]Bi, [sup 212]Po and [sup 213]At. The results may contribute to the understanding of the structure of the τ = 65 s isomer in [sup 212]Po. The new states identified include a J[sup π] = 49[sup +]/2 τ = 65 µs isomer in [sup 213]At which decays via an enhanced E3 transition whose strength is influenced by blocking. [ABSTRACT FROM AUTHOR]

High-spin states in [sup 108]Cd were studied following the reaction [sup 64]Ni([sup 48]Ca,4n) at a beam energy of 207 MeV. Gamma rays were detected using the Gammasphere array. Two rotational bands have been observed at very high angular momentum. Measurements of fractional Doppler shifts yielded lower limits for the quadrupole moments and showed that the observed structures are at least as deformed as the superdeformed structures e.g. in the A ≈ 150 region, and possibly exceed a 2:1 axis ratio. The existence of very extended shapes has been predicted by cranked Strutinsky calculations, and recent projected shell model calculations suggest that the πi[sub 13/2] hyper-intruder orbital is occupied in these newly observed bands. [ABSTRACT FROM AUTHOR]