An international research team succeeded in gaining new insights into the artificially produced superheavy element flerovium, element 114, at the accelerator facilities of the GSI Helmholtzzentrum für Schwerionenforschung in Darmstadt, Germany. Under the leadership of Lund University in Sweden and with significant participation of Johannes Gutenberg University Mainz (JGU) as well as the Helmholtz Institute Mainz (HIM) in Germany and other partners, flerovium was produced and investigated to determine whether it has a closed proton shell. The results suggest that, contrary to expectations, flerovium is not a so-called "magic nucleus." The results were published in the journal Physical Review Letters.
In the late 1960s, Sven-Gösta Nilsson, then a physics professor at Lund University, and others formulated a theory about the possible existence of still unknown superheavy elements. In the meantime, such elements have been created and many predictions have been confirmed. The discovery of the six new elements 107 to 112 was achieved at GSI in Darmstadt, and further ones up to element 118 are now known as well. Strongly increased half-lives for the superheavy elements due to a "magic" combination of protons and neutrons were also predicted. This occurs when the shells in the nucleus, each holding a certain number of protons and neutrons, are completely filled. "Flerovium, element 114, was also predicted to have such a completed, 'magic' proton shell structure. If this were true, flerovium would lie at the center of the so-called 'island of stability', an area of the chart of nuclides where the superheavy elements should have particularly long lifetimes due to the shell closures," explains Professor Dirk Rudolph of Lund University, who is the spokesperson of the international experiment.