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Shell Model Description of $^{158}$Gd

G. Popa·J. P. Draayer·J. G. Hirsch
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Abstract

The pseudo-SU(3) model is used to describe the low-energy spectra as well as $E2$ and $M1$ transition strengths in $^{158}$Gd. The Hamiltonian includes spherical single-particle energies, the quadrupole-quadrupole and proton and neutron pairing interactions, plus four rotor-like terms. The parameters of the Hamiltonian were fixed by systematics with the rotor-like terms determined through a least-squares analysis. The basis states are built as linear combinations of SU(3) states which are the direct product of SU(3) proton and neutron states with pseudo-spin zero. The calculated results compare favorably with the available experimental data, which demonstrates the ability of the model to describe such nuclei.

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G. Popa, J. P. Draayer, J. G. Hirsch. 2000-10-04. Shell Model Description of $^{158}$Gd. https://doi.org/10.1142/9789812799753_0075

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