Friday, 14 March, 1997 at 2pm

"White Dwarfs and the Age of the Galaxy"

Sandy Leggett - Joint Astronomy Centre

ABSTRACT: "New photometric and spectroscopic data have been obtained for a large sample of cool white dwarfs. These data have been analysed with state-of-the-art model atmospheres and effective temperatures and atmospheric compositions have been determined. Radii and masses have also been obtained for those stars with accurate parallax measurements. These high quality data and models allow us to produce an improved cool white dwarf luminosity function based on a proper motion sample. The turn-over seen at the faint end of this luminosity function, combined with theoretical cooling sequences enable us to constrain the age of the local region of the Galaxy."