Symmetries in nuclei near the centre of the f7/2 shell

High-spin states in the mirror pair nuclei 49Cr and 49Mn and their cross-conjugate partners, the mirror pair 47V and 47Cr have been investigated using experimental γ-ray spectroscopic techniques. The combination of high-efficiency EUROBALL cluster Germanium detectors and clean exit-channel gating afforded by a 31-element silicon ball used in conjunction with a 15-detector neutron wall allowed a revision and extension to the energy level schemes of all four nuclei up to Jπ=31-/2. The difference in excitation energy between states of equivalent spin in the parent nucleus and its analogue partner have thus been established for both mirror pairs up to the f7/2-shell band terminating state for the first time. This difference is assumed to be due almost entirely to the Coulomb effect and is therefore called the Coulomb energy difference (CED). The variation in the CED with spin has been interpreted as reflecting the change in the way the nucleus generates its angular momentum, from a collective rotational motion at low spin to a full non-collective alignment of the angular momentum vectors of the valence nucleons at the band termination. Furthermore, a comparison between the cross-conjugate mirror pairs indicates that the variation of the CED can be attributed to microscopic and macroscopic behaviours and so is shown to reflect the changing nuclear shape as a function of spin. States up to the f7/2-shell band termination at Jπ=15+ have been observed in the odd-odd N=Z=23 nucleus 46V. A revised and significantly extended level scheme contains two separate structures built upon the T=1 ground state, corresponding to spherical and prolate deformations of which the former is yrast. A rotational band in the latter structure has close correspondence with the yrast sequence in the analogue nucleus 46Ti and so is assigned as a T=1 configuration. The small discrepancy between their analogue states in the two nuclei is interpreted as a Coulomb effect caused by an np-pair alignment in 46V. Detailed comparisons with the results of full-fp shell model calculations are made for all five nuclei. These predictions are found to be in excellent agreement with the experimental results