12 May 2011

Speaker: Judith Cohen (Caltech)

Title: Cecilia Payne-Gaposchkin Lecture: 40 Years of Accurate Galactic Stellar Abundances

Abstract:In 1925, Cecilia Payne-Gaposchkin first showed spectral types to be primarily a sequence of stellar temperature with pressure (i.e. surface gravity) playing a smaller role. In this talk, I explore the third dimension of stellar spectra: metallicity. Our understanding and our ability to measure metallicity have evolved since the first non-solar metallicity stars were discovered 60 years ago. After a review of the production of the elements and galactic chemical evolution, I will present specific applications of precision abundance measurements from my work, including Galactic globular clusters, Galactic halo stars, and even potential Earth-like planet hosts.