ABSTRACT

White dwarfs represent the eventual end products of 98% of all stars. As such, their luminosity and mass distributions can be used to understand the properties of their progenitor populations (e.g., the initial mass function of stars). In this talk, I will summarize recent results from two large imaging and spectroscopic surveys aimed at uncovering these stellar cinders in nearby resolved clusters. With ultra-deep HST/ACS imaging of globulars, we have now firmly established the ages of the first structures to form in the Galactic halo and disk. A similar survey of white dwarfs in rich open clusters (over a large range of age and metallicity) has uncovered hundreds of these objects that can be spectroscopically studied. The data have led to unprecedented constraints on the initial-to-final mass relation (i.e., what mass main-sequence star maps to white dwarf mass) over a large mass range (M_initial = 1 -- 7 Msun), and therefore are a powerful input to chemical evolution models of galaxies including enrichment in the interstellar medium. Finally, I will discuss direct empirical evidence that stellar mass loss is much more efficient in high metallicity environments. This result is critical in interpreting the UV upturn in elliptical galaxies, the dearth of planets around white dwarfs, and the different rates (and properties) of type Ia SNe in elliptical vs spiral galaxies.