White Dwarfs in Globular Clusters - Progenitors, Successors and the Real Thing

Abstract

I will start by discussing the evolutionary status of the white dwarf *progenitors*, the hot UV bright stars. Observations of UIT-selected UV bright stars in globular clusters suggest that a high percentage of them manage to evolve from the horizontal branch to the white dwarf region without passing through the thermally pulsing AGB phase, thereby avoiding the planetary nebula stage. The white dwarf successors are stars experiencing a very late helium core flash while already on the helium white dwarf cooling curve. While they have been around theoretically for quite some time strong candidates could be verified only quite recently. And, last not least, the *white dwarfs* themselves offer new opportunities to derive distances and ages of globular clusters, which I will discuss. For a discussion of white dwarfs in binaries see the reviews by Adrienne Cool and Frank Verbunt in this volume.