Microscopic study of higher-order deformation effects on the ground states of superheavy nuclei around $^{270}$Hs

Abstract

We study the effects of higher-order deformations β λ (λ = 4, 6, 8, and 10) on the ground state properties of superheavy nuclei (SHN) near the doubly magic deformed nucleus 270 Hs by using the multidimensionally-constrained (MDC) relativistic mean-field (RMF) model with five effective interactions PC-PK1, PK1, NL3 * , DD-ME2, and PKDD. The doubly magic properties of 270 Hs are featured by the large energy gaps at N = 162 and Z = 108 in the single-particle spectra. By investigating the binding energies and single-particle levels of 270 Hs in multidimensional deformation space, we find that the deformation β6 has the greatest impact on the binding energy among these higher-order deformations and influences the shell gaps considerably. Similar conclusions hold for other SHN near 270 Hs. Our calculations demonstrate that the deformation β6 must be considered when studying SHN by using MDC-RMF.