Shape transitions and ground-state properties of tungsten isotopes in covariant density functional theory

Abstract

This study investigates the structural evolution of even-even tungsten isotopes (${}^{154\text{–}264}$W) using covariant density functional theory (CDFT) with four relativistic functionals: DD-ME1, DD-ME2, DD-PC1, and DD-PCX. Key nuclear properties, including binding energies, quadrupole deformation parameters, two-neutron separation energies, neutron pairing energies, nuclear radii, and potential energy curves, are analyzed to explore shape transitions and stability from neutron-deficient to neutron-rich isotopes up to the drip line. The results reveal a dynamic shape evolution, with spherical configurations at $N=82$ and $N=126$, prolate dominance in intermediate regions, and shape coexistence in isotopes such as ${}^{158}$W, ${}^{160}$W, ${}^{194}$W, ${}^{196}$W, ${}^{206}$W, and near ${}^{244\text{–}248}$W. A potential subshell closure at $N=118$ is identified, supported by anomalies in separation energies and vanishing pairing energies. The neutron drip line is predicted at $N=184$, marked by a return to spherical symmetry. Comparisons with experimental data and other theoretical models, including the deformed Hartree-Fock-Bogoliubov method with the Skyrme SLy4 interaction, the Finite Range Droplet Model, and the Relativistic Mean Field model with NL3, show strong agreement, validating the robustness of CDFT. These findings enhance our understanding of nuclear structure in the medium-to-heavy mass region and provide insights relevant to r-process nucleosynthesis, thereby guiding future experimental studies at radioactive ion beam facilities.

14 pages, 11 figures

References in corpus (20)

• Relativistic Continuum Hartree Bogoliubov Theory for Ground State Properties of Exotic Nuclei
• Neutron-Rich Nuclei in Heaven and Earth
• Relativistic Nuclear Energy Density Functionals: adjusting parameters to binding energies
• Hidden pseudospin and spin symmetries and their origins in atomic nuclei
• DIRHB -- a relativistic self-consistent mean-field framework for atomic nuclei
• Global performance of covariant energy density functionals: ground state observables of even-even nuclei and the estimate of theoretical uncertainties
• Charmonium in Medium: From Correlators to Experiment
• Role of triaxiality in the ground state shape of neutron rich Yb, Hf, W, Os, and Pt isotopes
• Shape transitions in neutron-rich Yb, Hf, W, Os, and Pt isotopes within a Skyrme Hartree-Fock + BCS approach
• Exploring the extended density-dependent Skyrme effective forces for normal and isospin-rich nuclei to neutron stars
• Optimizing the relativistic energy density functional with nuclear ground state and collective excitation properties
• Shape coexistence in even-even nuclei: A theoretical overview
• The proxy-SU(3) symmetry in atomic nuclei
• Toward a bridge between relativistic and nonrelativistic density functional theories for nuclei
• Bubble nuclei with shape coexistence in even-even isotopes of Hf to Hg
• Additivity of effective quadrupole moments and angular momentum alignments in the A~130 nuclei
• A study of nuclear radii and neutron skin thickness of neutron-rich nuclei near the neutron drip line
• Shell Evolution in Neutron-rich Ge, Se, Kr and Sr Nuclei within RHB Approach
• Microscopic Investigation of Ground State Properties and Shape Evolution in Osmium Isotopes
• Investigation of ground state properties and shape evolution in Hf isotopes using the CDFT approach