Rotational alignment near N=Z and proton-neutron correlations

The effects of the residual proton-neutron interactions on bandcrossing fea tures are studied by means of shell model calculations for nucleons in a hi gh-j intruder orbital. The presence of an odd-nucleon shifts the frequency of the alignment of two nucleons of the other kind along the axis of rotati on. It is shown that the anomalous delayed crossing observed in nuclei with aligning neutrons and protons occupying the same intruder subshell can be partly attributed to these residual interactions. [S0556-2813(99)00503-8].