Impacts of hexadecapole correlations in actinide nuclei
arXiv:2607.26499 · doi:10.1103/n5xp-fntr
The paper investigates how hexadecapole correlations affect low‑energy spectra and transition strengths of actinide nuclei (Th, U, Pu) using a mapped sdg interacting boson model constrained by Gogny D1S Hartree‑Fock‑Bogoliubov calculations.
Abstract
The impact of hexadecapole correlations on the low-energy spectroscopic properties of Th, U, and Pu nuclei, within the mass range $232 \le A \le 240$, is studied systematically using the mapped $sdg$-IBM model. Fermionic input is obtained via the quadrupole-hexadecapole constrained Hartree-Fock-Bogoliubov approximation, based on the parametrization D1S of the Gogny energy density functional. The $sdg$-IBM Hamiltonian parameters are determined by mapping the quadrupole-hexadecapole fermionic mean-field potential energy surfaces onto the corresponding bosonic surfaces. The low-energy spectra and transition strengths, obtained via the diagonalization of the $sdg$-IBM Hamiltonian, compare well with the available experimental data. It is shown that the effects of hexadecapole collectivity can be observed in high-spin yrast states with spins $J^Ï \geqslant 10^{+}$. The mapped $sdg$-IBM improves the excitation energies of those states, as compared with the simpler $sd$-IBM model. The $sdg$-IBM also improves the description of the $E2$ transition strengths between high-spin yrast states and predicts strong $E4$ transitions from nonyrast $4^+$ states to the $0^+$ ground state.
14 pages, 10 figures