Superdeformation in the newly discovered superheavy elements

Abstract

The structures of newly discovered superheavy elements with the proton number Z=110–112, 114, 116, 118 and of their α-decay chain nuclei are investigated using the self-consistent relativistic mean-field (RMF) theory. Extensive calculations show that the experimental data on the α-decay energies are well reproduced by the RMF theory. We find sometimes shape coexistence in superheavy nuclei and a superdeformed prolate configuration becomes the ground state of the new superheavy elements. The superdeformation could lead to a slightly deeper binding and give a longer lifetime for superheavy nuclei than expected. This may be a new mechanism for the appearance of the superheavy island. A systematic comparison with other models for the calculated binding energies and deformations is carried out, and predictions on the properties of unknown neighbouring superheavy nuclei are made for further comparison with future experiments.