Effects of shape coexistence and configuration mixing on low-lying states in tellurium isotopes

Abstract

Low-energy quadrupole collective states in even-even tellurium (Te) isotopes are studied using the interacting boson model with configuration mixing. The corresponding Hamiltonian is determined by means of the microscopic nuclear structure calculations within the self-consistent mean-field method employing a given energy density functional and pairing interaction. Calculated low-energy levels for nonyrast states show a parabolic behavior characteristic of the shape-coexisting structure. The intruder prolate-shape configuration is shown to mix strongly with the normal oblate-shape configuration, and play an important role in determining the low-lying structure in the Te isotopes near the middle of the neutron major shell closures.

Figures (11)

• Figure 1: Potential energy surfaces in terms of the quadrupole deformations $\beta$ and $\gamma$ for the $^{108-126}$Te isotopes calculated by the constrained RHB-SCMF method employing the DD-PC1 EDF and a separable pairing force. The global minimum is indicated by the solid circle. See the main text for details.
• Figure 2: Same as the caption to Fig. \ref{['fig:pes1']}, but for the mapped bosonic PESs.
• Figure 3: Derived Hamiltonian parameters for the IBM-2 and those for the IBM2-CM corresponding to the normal and intruder configurations, mixing strength and energy offset $\Delta$ of \ref{['eq:delta2']} for the studied Te nuclei.
• Figure 4: (a) Experimental datamihai2011doncel2017vonspee2024 and (b) calculated excitation energies of low-lying states for the even-even $^{108-126}$Te isotopes. The calculations are based on the IBM2-CM for $^{114-122}$Te, and on the IBM-2 with a single configuration for other nuclei.
• Figure 5: Predicted low-energy spectra for $^{118}$Te from the IBM-2 and IBM2-CM, and the experimental data mihai2011.