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Precession Mode on High-K Configurations: Non-Collective Axially-Symmetric Limit of Wobbling Motion

Yoshifumi R. Shimizu·Masayuki Matsuzaki·Kenichi Matsuyanagi
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Abstract

We have studied the precession mode, the rotational excitation built on the high-$K$ isomeric state, in comparison with the recently identified wobbling mode. The random-phase-approximation (RPA) formalism, which has been developed for the nuclear wobbling motion, is invoked and the precession phonon is obtained by the non-collective axially-symmetric limit of the formalism. The excitation energies and the electromagnetic properties of the precession bands in $^{178}$W are calculated, and it is found that the results of RPA calculations well correspond to those of the rotor model; the correspondence can be understood by an adiabatic approximation to the RPA phonon. As a by-product, it is also found that the problem of too small out-of-band $B(E2)$ in our previous RPA wobbling calculations can be solved by a suitable choice of the triaxial deformation which corresponds to the one used in the rotor model.

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Yoshifumi R. Shimizu, Masayuki Matsuzaki, Kenichi Matsuyanagi. 2005-07-19. Precession Mode on High-K Configurations: Non-Collective Axially-Symmetric Limit of Wobbling Motion. https://doi.org/10.1088/0031-8949%2F2006%2Ft125%2F031

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