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Wobbling excitations in 156Dy and 162Yb

Jan Kvasil·Rashid G. Nazmitdinov
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Abstract

We study in the cranked Nilsson plus random phase approximation low-lying quadrupole excitations of positive parity and negative signature in 156Dy and 162Yb at high spins. Special attention is paid to a consistent description of wobbling excitations and their identification among excited states. A good agreement between available experimental data and the results of calculations is obtained. We found that in 156Dy the lowest odd spin gamma-vibrational states transform to the wobbling excitations after the backbending, associated with the transition from axially-symmetric to nonaxial shapes. Similar results are predicted for 162Yb. The analysis of electromagnetic transitions, related to the wobbling excitations, determines uniquely the sign of the gamma-deformation in 156Dy and 162Yb after the transition point.

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Jan Kvasil, Rashid G. Nazmitdinov. 2006-11-16. Wobbling excitations in 156Dy and 162Yb. https://arxiv.org/abs/nucl-th/0611059

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