Duke Physics Colloquium: Abundance Anomalies in Globular Clusters - Does the Fault Lie in the Stars?

"Abundance Anomalies in Globular Clusters - Does the Fault Lie in the Stars?" - Globular clusters are the oldest structures to form in the galaxy and thus their ages provide a wealth of information about the evolution of the Milky Way. These ages assume that we understand stellar evolution and the chemical history of the clusters and both have been called into question by observations. For example, clusters exhibit anomalous elemental and isotopic abundance patterns as compared with isolated stars, the best studied being the anticorrelation between sodium and oxygen. Various models have been constructed to explain this effect and some call into question the initial assumptions that go into determining the ages of clusters. One way to understand the origin of these anomalies is to measure the relevant nuclear reactions and I'll describe how we go about doing that and where we stand in addressing this puzzle.