Shell model and mean-field description of band termination in the A∼44 nuclei

We study nuclear high-spin states undergoing the transition to the fully stretched configuration with maximum angular momentum I-max within the space of valence nucleons. To this end, we perform a systematic theoretical analysis of non-fully-stretched I-max-2 and I-max-1 f(7/2)(n) seniority isomers and d(3/2)(-1)f(7/2)(n+1) intruder states in the A similar to 44 nuclei from the lower-fp shell. We employ two theoretical approaches: (i) the density functional theory based on the cranked self-consistent Skyrme-Hartree-Fock method, and (ii) the nuclear shell model in the full sdfp configuration space allowing for 1p-1h cross-shell excitations. We emphasize the importance of restoration of broken angular momentum symmetry inherently obscuring the mean-field treatment of high-spin states. Overall good agreement with experimental data is obtained.