Dynamical moments and relative alignments

A mixing of two common-symmetry orbitals that approach each other at the Fermi energy creates non-converged HF solutions for certain values of as discussed in Sec. 3.4, and introduces large errors in the observables calculated in this article except, perhaps, for energies and multipole moments. Indeed, in many cases of non-converging solutions, due to the variational character of the HF equations, the total energies are almost correct, namely, they can be smoothly followed through the crossing region. However, errors in the total spins can be much larger, because the non-converged solutions correspond to almost-random mixtures of two interacting orbitals that are very close in energy but may significantly differ in spin. Then, neither the relative alignments, nor, especially, the dynamical moments, can be smoothly followed along the crossing region. Therefore, in the figures presented in this section, we removed all points corresponding to the non-converged solutions; the absence of some points was compensated for by drawing straight lines between points corresponding to the converged solutions.

In Fig. 9 are reported the dynamical moments
=
,
calculated for the
near-yrast bands in ^{32}S. One can see, that bands with
the same intruder contents present very similar behavior, as
far as the dynamical moments are concerned. It appears
clearly from the figure that bands based on the and/or 3^{0} configurations have in general (especially at
high rotational frequencies) much lower dynamical moments
than the magic 3^{2}3^{2} SD band.
The bands based on higher numbers of occupied intruder states
(not shown in the figure), have higher values of
,
along with a larger distance from the yrast line.

In Fig. 10 are drawn the relative alignments,
=*I*(band)-*I*(SD 3^{2}3^{2} band), of near-yrast
bands in ^{32}S calculated with respect to the magic
3^{2}3^{2} band in the same nucleus. One can see that
again the results obtained for various bands depend
mainly on the numbers of occupied intruder states. It is
very difficult for the nucleus to build up spin, when few
intruder orbitals are occupied, and therefore one observes a
lowering of the relative alignments for these bands. One may
discuss these questions more clearly by introducing the
relative alignments of bands in neighboring nuclei,
presented in Sec. 5.

All the calculated features of SD bands in ^{32}S seem to
reflect in a very direct way the crucial role
played by the intruder orbitals. Such an observation
may, therefore, similarly as in other SD regions, serve
as a guideline in theoretical analyses, as well as in
experimental investigations of properties of SD bands in
the *A*30 mass region.