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arXiv · 2209.09463

Collective-model description of shape coexistence and intruder states in cadmium isotopes based on a relativistic energy density functional

K. Nomura·K. E. Karakatsanis
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Abstract

Low-energy structure of even-even $^{108-116}$Cd isotopes is analyzed using a collective model that is based on the nuclear density functional theory. Spectroscopic properties are computed by solving the triaxial quadrupole collective Hamiltonian, with parameters determined by the constrained self-consistent mean-field calculations within the relativistic Hartree-Bogoliubov method employing a universal energy density functional and a pairing force. The collective Hamiltonian reproduces the observed quadrupole phonon states of vibrational character, which are based on the moderately deformed equilibrium minimum in the mean-field potential energy surface. In addition, the calculation yields a low-lying excited $0^+$ band and a $\gamma$-vibrational band that are associated with a deformed local minimum close in energy to the ground state, consistently with the empirical interpretation of these bands as intruder bands. Observed energy spectra, $B(E2)$, and $\rho^2(E0)$ values are, in general, reproduced reasonably well.

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K. Nomura, K. E. Karakatsanis. 2022-09-20. Collective-model description of shape coexistence and intruder states in cadmium isotopes based on a relativistic energy density functional. https://doi.org/10.1103/physrevc.106.064317

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