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arXiv · 1203.1873

Non-yrast nuclear spectra in a model of coherent quadrupole-octupole motion

N. Minkov·S. Drenska·M. Strecker·W. Scheid·H. Lenske
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Abstract

A model assuming coherent quadrupole-octupole vibrations and rotations is applied to describe non-yrast energy sequences with alternating parity in several even-even nuclei from different regions, namely $^{152,154}$Sm, $^{154,156,158}$Gd, $^{236}$U and $^{100}$Mo. Within the model scheme the yrast alternating-parity band is composed by the members of the ground-state band and the lowest negative-parity levels with odd angular momenta. The non-yrast alternating-parity sequences unite levels of $β$-bands with higher negative-parity levels. The model description reproduces the structure of the considered alternating-parity spectra together with the observed B(E1), B(E2) and B(E3) transition probabilities within and between the different level-sequences. B(E1) and B(E3) reduced probabilities for transitions connecting states with opposite parity in the non-yrast alternating-parity bands are predicted. The implemented study outlines the limits of the considered band-coupling scheme and provides estimations about the collective energy potential which governs the quadrupole-octupole properties of the considered nuclei.

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N. Minkov, S. Drenska, M. Strecker, W. Scheid, H. Lenske. 2012-03-08. Non-yrast nuclear spectra in a model of coherent quadrupole-octupole motion. https://doi.org/10.1103/physrevc.85.034306

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