The production of six new heavy isotopes promises to shed light on the shell model for nuclear structure of the periodic table's heavier elements.

The new nuclei — which fit into the periodic table between rutherfordium (element 104) and the as-yet-unnamed element 114 — were created in a single radioactive decay chain by Paul Ellison at the Lawrence Berkeley National Laboratory in California and his co-workers. They made the isotopes by hitting targets of plutonium-242 with an intense beam of calcium-48 nuclei, setting off a chain of decays from a nucleus of element 114.

The isotopes' lifetimes ranged from eight-thousandths of a second to just over three minutes. Creating such short-lived isotopes was necessary to generate several examples of the heaviest elements before the nuclei fissioned into two similar-sized parts.

Phys. Rev. Lett. 105, 182701 (2010)