Shell-model description ofN≃Z1f7/2nuclei

Abstract

The available spectroscopic data for nuclei middle and second half of the $1{f}_{7/2}$ shell are well reproduced by shell-model calculations. For natural parity states of several odd-A nuclei, a comparison of shell-model calculations in the full pf configuration space with the Nilsson diagram and particle-rotor predictions shows that prolate strong coupling applies at low excitation energy. Multiquasiparticle rotational bands and, in some cases, band crossings have been revealed. Coriolis decoupling effects are observed only in nuclei at the beginning of the shell. The ground state bands experience a change from a collective to a noncollective regime, approaching the termination in the $1{f}_{7/2}^{n}$ space. Similar features are observed in the even-even $N\phantom{\rule{0.3em}{0ex}}=\phantom{\rule{0.3em}{0ex}}Z$ nuclei $^{48}\mathrm{Cr}$ and $^{52}\mathrm{Fe}$ and $N=Z+2$ nuclei $^{46}\mathrm{Ti}$ and $^{50}\mathrm{Cr}$. Evidence of the vibrational \ensuremath{\gamma} band is discussed in the $N=Z$ nuclei. A brief review is also presented for unnatural parity levels.