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Anharmonic double-phonon excitations in the interacting boson model

J. E. Garcia-Ramos·J. M Arias·P. Van Isacker
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Abstract

Double-$γ$ vibrations in deformed nuclei are analyzed in the context of the interacting boson model. A simple extension of the original version of the model towards higher-order interactions is required to explain the observed anharmonicities of nuclear vibrations. The influence of three- and four-body interactions on the moments of inertia of ground- and $γ$-bands, and on the relative position of single-$γ$ and double-$γ$ bands is studied in detail. As an example of a realistic calculation, spectra and transitions of the highly $γ$-anharmonic nuclei $^{164}$Dy, $^{166}$Er, and $^{168}$Er are interpreted in this approach.

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J. E. Garcia-Ramos, J. M Arias, P. Van Isacker. 2000-07-13. Anharmonic double-phonon excitations in the interacting boson model. https://doi.org/10.1103/physrevc.62.064309

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