Creating and studying radioactive molecules advances nuclear structure and fundamental symmetry studies

An international team performed the world’s first measurement of how the size of the radium nucleus modifies the structure of molecules containing different radium isotopes. The research used a combination of lasers and ion traps at the Isotope mass Separator On-Line (ISOLDE) Radioactive Ion Beam Facility at CERN. The team studied the quantum structure of radium monofluoride (RaF) molecules. Quantum structure dictates the energy levels and how these levels change under different conditions. Scientists predict that RaF molecules are useful for studying the violation of certain fundamental symmetries found in nature. The team measured the changes in electronic energy levels when one of the radium nuclei was replaced with a different isotope. This demonstrates the extreme sensitivity of these molecules to the interaction of electrons and nuclei at short distances.