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Superbands, responsible for the backbending in156Dy and other N=90 and N=88 nuclei, are proposed to be alignedn(i13/2)2 bands, whereas it is argued that the recently discovered positive parity band in156Dy withIπ= (2+) up to 10+ members does not constitute the low spin extension of the superband.

Analysis of level energies in aligned octupole bands in even-even deformed nuclei using the VMI-model expressed in terms of the rotational angular momentumR, show that almost complete alignment is reached at low spin values. It is shown that the alignment is almost spin independant. Using the ground-state band VMI-parameters only a renormalization of the alignment parameter 〈J⊥〉 is enough to reproduce the level energies of the NPB's.