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arXiv · 2510.16453

Microscopic triaxial quadrupole-octupole collective Hamiltonian for low-energy nuclear excitations

J. Xiang·J. Zhao·Z. P. Li·D. Vretenar
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Abstract

We present a microscopic triaxial quadrupole-octupole collective Hamiltonian (TQOCH) that unifies collective rotations, quadrupole-octupole vibrations, and their couplings to model low-lying nuclear states of both parities. The TQOCH's dynamics are governed by collective parameters derived from multidimensionally constrained covariant density functional theory. The model's validity is demonstrated through calculations of $^{152}$Sm, including its deformation energy surfaces, excitation spectra, and transition probabilities. As a predictive tool, the TQOCH probes complex nuclear phenomena like shape coexistence and phase transitions, directly connecting their microscopic origins to spectroscopic observables.

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J. Xiang, J. Zhao, Z. P. Li, D. Vretenar. 2025-10-18. Microscopic triaxial quadrupole-octupole collective Hamiltonian for low-energy nuclear excitations. https://arxiv.org/abs/2510.16453

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