Gold cannot form until certain unstable atomic nuclei break apart. Exactly how those nuclear transformations unfold has long been difficult to determine. Now, nuclear physicists at the University of Tennessee (UT) report three discoveries in a single study that clarify important parts of this process. Their findings could help researchers build improved models of the stellar events that create heavy elements and better predict the behavior of exotic atomic nuclei.
Heavy elements such as gold and platinum are forged under extraordinary conditions, including when stars collapse, explode, or collide. These events trigger the rapid neutron capture process (or r-process for short). During this process, an atomic nucleus absorbs neutrons in rapid succession. As the nucleus grows heavier and more unstable, it eventually breaks down into lighter and more stable forms.
Along this pathway across the nuclide chart, a common sequence involves beta decay of the parent nucleus followed by the release of two neutrons. The atomic nuclei involved in these reactions are extremely rare and unstable, making them difficult or even impossible to study directly in experiments. Because of this, scientists rely heavily on theoretical models, which must be tested and refined using laboratory data.
