Potential energy surfaces and spectra of superheavy elements

The potential energy surfaces of some superheavy nuclei are determined, using a mapping from the microscopic shell model space to a geometrical model. The content of the shell model space is determined through the knowledge of the absolute deformation and a single-particle spectrum as a function of deformation. Both have to be extracted from a microscopic model. We show that one cannot restrict to only prolate or oblate deformations because the content of the microscopic space already implies triaxiality. Also cases of $\gamma$ instability occur. The mass parameter of ${}^{254}\mathrm{No}$ is determined through the knowledge of at least one rotational state of the ground-state band. Assuming the same mass parameter for the other superheavy elements, the spectrum of each of them is determined. The following superheavy nuclei are considered: ${}^{254}\mathrm{No}$, ${}^{260}\mathrm{Rf}$, ${}^{262}\mathrm{Sg}$, ${}^{270}\mathrm{Hs}$, ${}^{274}110\left(\text{Ds}\right)$, ${}^{276}112$, and ${}^{290}114$, where ${}^{260}\mathrm{Rf}$ and ${}^{262}\mathrm{Sg}$ turn out to be $\gamma$ unstable.

Figure 1

The potential energy surface of the isotopes considered in the text. Each isotope is represented by two figures. The one on top of each sequence gives the result of the deduced PES with the method explained in Sec. 2. In the bottom part of each sequence the approximation via the potential within the generalized collective model (GCM) is given.

Figure 2

Sections of the PES along the $\gamma$ direction for the following superheavy nuclei ${}^{254}\mathrm{No}$, ${}^{260}\mathrm{Rf}$, ${}^{262}\mathrm{Sg}$, ${}^{270}\mathrm{Hs}$, ${}^{274}110\left(\text{Ds}\right)$, and ${}^{276}112$.

Figure 3

Spectra of the isotopes discussed in the text.