New Elements, Nuclear Chemistry, and Nuclear Forensics at the Bottom of the Periodic Table
Prof. Cody Folden
Department of Chemistry
Texas A&M University
Heavy element nuclear science has a number of important unanswered questions, including “How should the next new element be discovered?”, “What are the chemical properties of the heaviest elements?”, and “How can the history of forensic samples be determined?” The Heavy Elements Group at Texas A&M addresses all of these questions from a number of angles. In recent years, we have studied the influence of compound nucleus survival on cross sections for fusion-evaporation reactions by systematically varying the proton and neutron numbers of the projectile and target nuclei. These results show the critical importance of survival and provide guidance to new element searches being conducted worldwide. We have also developed new techniques for characterizing the chemical properties of very heavy elements. Today, most such experiments focus on adsorbing the heavy atom onto a surface, so we have pioneered the use of self-assembled monolayers of organic compounds for this purpose. This work has been complemented by a successful collaboration to conduct experiments utilizing vacuum chromatography, where chemical measurements can be conducted within hundreds of milliseconds of production. Finally, our group has worked to understand the history of uranium samples irradiated with neutrons. Using a combination of reactor simulations and intra-elemental isotopic ratio measurements, we have been able to reconstruct the history of multiple samples. Similar techniques were applied to a plutonium sample that was convincingly shown to have been produced during the Manhattan Project. This talk will discuss these projects, the most recent results, and future plans.
Hosted by Prof. Couder