The Luminosity Function of White Dwarfs

  title={The Luminosity Function of White Dwarfs},
  author={James William Liebert and Conard C. Dahn and David G. Monet},
  journal={The Astrophysical Journal},
Trigonometric parallaxes, optical colors, and spectrophotometry are used to derive an empirical luminosity function for cool white dwarfs using the 1/V(max) method. To facilitate comparison with theoretical cooling curves, relations for cool white dwarfs are estimated for T(eff) versus M(V) and for M(V) versus M(bol). The results show that a downturn occurs in the distribution of cool degenerate stars near log luminosity equals about -4.4. The indicated local space density of observed… Expand
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