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High-angular-momentum states in 64Zn were populated in the 40Ca( 28Si,4p) reaction at a beam energy of 122 MeV. Evaporated, light, charged particles were identified by the Microball, while γ rays were detected using the Gammasphere array. The main focus of this paper is on two strongly coupled, collective bands. The yrast band, which was previously known, has been linked to lower-lying states establishing the excitation energies and angular momenta of in-band states for the first time. The newly identified excited band decays to the yrast band but firm angular-momentum assignments could not be made. In order to interpret these structures cranked-Nilsson-Strutinsky calculations have been performed. The calculations have been extended to account for the distribution of nucleons within a configuration. The yrast collective band is interpreted as based on the π(f 7/2) -1(p 3/2f 5/2) 2(g 9/2) 1 ν(p 3/2f 5/2) 4(g 9/2) 2 configuration. There are several possible interpretations of the second band but it is difficult to distinguish between the different possibilities.

High-spin states in 3572Br37 were studied using the 40Ca(36Ar, 3pn) reaction. The existing level scheme has been significantly modified and extended. Evidence has been found for a spin reassignment of -1ℏh to the previously observed negative-parity band, which carries implications for the interpretation of a signature inversion in this structure. One signature of the previously assigned positive-parity band is interpreted as negative parity and has been extended to I π=(22-) and its signature partner has been observed up to Iπ = (19-) for the first time. The remaining positive-parity band has been extended to Iπ=(29+). A sequence of states observed to Iπ=(22+) may be the signature partner of this structure. Configurations have been assigned to each of these three structures through comparisons to cranked Nilsson-Strutinsky calculations.

The decay-out process of the yrast superdeformed band in 59Cu was studied. The spin, parity, excitation energy and the configuration of states were determined. A theoretical model was introdued that included a residual interaction and tunneling matrix element between the bands. The decay was found to occur through a small number of observed doorway states.

The nucleus 68Ge has been studied by gamma-ray spectroscopy following its population at high spin in the reaction 40Ca(32S,4p) 68Ge. The reaction channel was selected with the Microball array and gamma rays were detected with the Gammasphere array. The level scheme is very complex, reflecting the many different, and presumably mixed, excitation modes in this nucleus. Nevertheless, there appear to be some simplifications in the spin range above 18ℏ where we have identified a superdeformed band and several terminating bands. The results are compared with a cranked Nilsson-Strutinsky model without pairing.

The gamma decay of excited states in the nucleus 100Cd, which is two proton holes and two neutrons away from doubly magic (N=Z=50) 100Sn, has been studied with the Gammasphere array following the 46Ti(58Ni,2p2n) reaction at 215 MeV. Residues were identified by detection of evaporated charged particles in the Microball CsI array, by neutron detection in a set of liquid scintillator detectors, and by a tag on the delayed gamma-ray decay of the known 8+ isomeric state. The level scheme has been extended up to 20ℏ in angular momentum and to nearly 10 MeV in excitation energy. The results are compared with shell-model calculations.

The doubly magic superdeformed band in the N = Z nucleus 60Zn has been identified. Linking transitions connecting this band to the yrast line provide the first spin, parity, and excitation energy measurements for superdeformed states in the A˜60 region. The stretched- E2 character and relatively large B(E2) values of these transitions suggest a nonstatistical decay-out process.