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Partial Dynamical SU(3) Symmetry and the Nature of the Lowest K=0 Collective Excitation in Deformed Nuclei

A. Leviatan·I. Sinai
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Abstract

We discuss the implications of partial dynamical SU(3) symmetry (PDS) for the structure of the lowest K=0^{+} (K=0_2) collective excitation in deformed nuclei. We consider an interacting boson model Hamiltonian whose ground and gamma bands have good SU(3) symmetry while the K=0_2 band is mixed. It is shown that the double-phonon components in the K=0_2 wave function arise from SU(3) admixtures which, in turn, can be determined from absolute E2 rates connecting the K=0_2 and ground bands. An explicit expression is derived for these admixtures in terms of the ratio of K=0_2 and gamma bandhead energies. The SU(3) PDS predictions are compared with existing data and with broken-SU(3) calculations for ^{168}Er.

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A. Leviatan, I. Sinai. 1999-12-30. Partial Dynamical SU(3) Symmetry and the Nature of the Lowest K=0 Collective Excitation in Deformed Nuclei. https://doi.org/10.1103/physrevc.60.061301

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