Projected shell model study on nuclei near, the N = Z line

Study of the Napproximate toZ nuclei in the mass-80 region is not only interesting due to the existence of abundant nuclear-structure phenomena, but also important in understanding the nucleosynthesis in the rp-process. It is difficult to apply a conventional shell model due to the necessary involvement of the g(9/2) sub-shell. In this paper, the projected shell model is introduced to this study. Calculations Are systematically performed for the collective levels as well as the quasi-particle excitations. It is demonstrated that calculations with this truncation scheme can achieve a comparable quality as the large-scale shell model diagonalizations for Cr-48, but the present method can be applied to much heavier mass regions. While the known experimental data of the yrast bands in the Napproximate toZ nuclei (from Se to Ru) are reasonably described, the present calculations predict the existence of high-K states, some of which lie low in energy under certain structure conditions.