UNC-CH Physics and Astronomy Thesis Proposal

Mackenna Wood

“Lithium Depletion Ages of Newly Discovered and Poorly Studied Young Moving Groups”

Cluster ages are critical for benchmarking models of stellar evolution and understanding planet formation and evolution. In the age of Gaia, we are discovering new stellar associations and thousands of new members to existing groups. With accurate ages, new groups will provide unmatched samples of nearby stars in a well-defined evolutionary sequence. Young groups in particular provide excellent benchmarks to study stellar and planetary evolution, and TESS has already found several transiting planets in such groups. However, commonly used methods of measuring age, such as isochrone fitting and gyrochronology are imprecise. By using a more precise method, such as the lithium depletion boundary, we will not only obtain accurate ages for these new young associations, but will then be able to use them to test and calibrate other methods of age measurement. I propose to identify the Lithium Depletion Boundary in a number of newly discovered, or recently expanded young moving groups and stellar associations.