Nuclear Theory·nucl-th

Wednesday·August 21, 2024

11 papers—2 primary·9 cross-listed

01
$K$ -isomeric states in the isotopic and isotonic chains of $^{178}$ Hf
N. Minkov🇧🇬 · L. Bonneau🇫🇷 · P. Quentin🇫🇷 · J. Bartel🇫🇷 · H. Molique🇲🇾 · Meng-Hock Koh🇲🇾
We study the evolution of $K^{π} = 6^{+}$ and $8^{-}$ two-quasiparticle (q.p.) configurations in the isotopic and isotonic chains of even-even deformed nuclei around $^{178}$ Hf and their ability to describe series of observed $K$ -isomer excitations within the framework of a Skyrme Hartree--Fock--BCS (SHFBCS) approach using SIII interaction and seniority pairing strengths with self-consistent blocking. We apply the approach along the prescription in [Phys. Rev. C {\bf 105}, 044329 (2022)] used to describe $K$ -isomers in the actinide and transfermium mass regions. The calculations allow us to identify the regions where proton or neutron configurations or their mixture may be responsible for the $K$ -isomer formation. The obtained results provide a detailed test for the Skyrme SIII interaction used and outline the limits of applicability of the overall SHFBCS approach in the regions of well deformed nuclei. The study suggests that similar systematic analysis can be implemented in the heavier mass regions whenever enough data are available.
nucl-thPRC(2024)·3 citations
02
Skyrme-Hartree-Fock-BCS approach to $^{229 m}$ Th and neighboring nuclei
Nikolay Minkov🇧🇬 · Adriana Pálffy🇩🇪 · Philippe Quentin🇫🇷 · Ludovic Bonneau🇫🇷
The microscopic origin of the $^{229 m}$ Th isomer and its possible manifestation also in neighboring nuclei is explored within a selfconsistent Skyrme Hartree-Fock plus Bardeen-Cooper-Schrieffer approach. By using the well established SIII Skyrme parametrization, without any special adjustments related to low-energy isomer, the single-particle spectrum provided by the model reproduces the correct isomer $K^{π} = 3/ 2^{+}$ spin and parity, and the relative proximity of the isomeric state to the $K^{π} = 5/ 2^{+}$ ground state, yet on the keV scale. We show that this approach may provide microscopic estimates for some related observables, such as the quadrupole and octupole moments, deformation parameters as well as magnetic dipole moments. Its ability to provide a prediction for the M1 isomer transition probability is discussed. The obtained $^{229}$ Th single-particle structure is compared with that provided by calculations in neighbouring actinide isotopes and isotones, allowing us to assess the more general role of the considered mechanism for the formation of low-energy isomers.
nucl-thPRC(2024)·12 citations

Affiliations

first authorsco-authorsvia INSPIRE

K-isomeric states in the isotopic and isotonic chains of 178Hf

Skyrme-Hartree-Fock-BCS approach to 229mTh and neighboring nuclei

Affiliations

$K$ -isomeric states in the isotopic and isotonic chains of $^{178}$ Hf

Skyrme-Hartree-Fock-BCS approach to $^{229 m}$ Th and neighboring nuclei