Covariant density functional theory input for r -process simulations in actinides and superheavy nuclei: The ground state and fission properties

• Published in: Physical review. C 2020-11, Vol.102 (5), Article 054330
• Main Authors: Taninah, A., Agbemava, S. E., Afanasjev, A. V.
• Format: Article
• Language: English
• Subjects: 190 ≤ A ≤ 219; A ≥ 220; Alpha decay; Fission; Nuclear binding; Nuclear density functional theory; NUCLEAR PHYSICS AND RADIATION PHYSICS; Nuclear structure & decays; Nucleosynthesis in explosive environments
• ISSN: 2469-9985; 2469-9993
• DOI: 10.1103/PhysRevC.102.054330

A systematic investigation of the ground-state and fission properties of even-even actinides and superheavy nuclei with Z = 90–120 from the two-proton up to two-neutron drip lines with proper assessment of systematic theoretical uncertainties has been performed for the first time in the framework of covariant density functional theory (CDFT). Furthermore, these results provide a necessary theoretical input for the r-process modeling in heavy nuclei and, in particular, for the study of fission cycling. Four state-of-the-art globally tested covariant energy density functionals (CEDFs), namely, DD-PC1, DD-ME2, NL3*, and PC-PK1, representing the major classes of the CDFT models are employed in the present paper. Ground-state deformations, binding energies, two-neutron separation energies, α-decay Qα values and half-lives, and the heights of fission barriers have been calculated for all these nuclei. Theoretical uncertainties in these physical observables and their evolution as a function of proton and neutron numbers have been quantified and their major sources have been identified. Spherical shell closures at Z = 120, N = 184, and N = 258 and the structure of the single-particle (especially, high-j) states in their vicinities as well as nuclear matter properties of employed CEDFs are two major factors contributing to theoretical uncertainties. However, different physical observables are affected in a different way by these two factors. For example, theoretical uncertainties in calculated ground-state deformations are affected mostly by the former factor, while theoretical uncertainties in fission barriers depend on both of these factors.