Dr. Rod Clark
Nuclear Science Division
Lawrence Berkeley National Laboratory
Where does the Periodic Table end? What combinations of protons and neutrons can make up heaviest atomic nuclei? With the addition of four new elements in 2015, the seventh row of the table is now complete, but answers to such basic questions remain elusive. I will present a review of the current status of the topic, and recent controversies in the field, including the failure to directly determine the atomic number, Z, and mass number, A, of many of the newly discovered superheavy isotopes. Then I will turn to describing new efforts at Berkeley Lab aimed at addressing outstanding issues. For instance, the alpha decay and fission processes ultimately determine how long a nucleus will survive but it has recently been suggested that cluster decay may become the dominant decay mode for some superheavy nuclei. Another example is the occurrence of metastable states, which can have substantial hindrance to fission and alpha decay, and may become much longer lived than the ground state of the same nucleus. Such results have tremendous implications for how far we may be able to push the experimental studies of the heaviest elements.
Hosted by Prof. Wiescher