Inertia tensor and fine structure of scissors-mode resonances

In a recent paper it has been shown that a number of rare-earth elements have a definite deviation from axial symmetry, with the triaxiality angle gamma >= 8 degrees and the ratios of the components of the inertia tensor in qualitative agreement with the irrotational model. Such results have been extracted from experimental data within the J-2 subspace, but scissors-mode resonances, which are most sensitive to the nuclear shape, were not included in the analysis. The irrotational and rigid inertia tensors have an opposite dependence on the triaxiality angle gamma and this affects in a striking way the fine structure of scissors-mode resonances.