Luminosity function suggests up to 100 white dwarfs within 20 pc may be hiding in multiple systems

Boaz Katz, Subo Dong, Doron Kushnir

We examine the luminosity function of white dwarfs (WDs) in the local ``complete'' WD sample ($d<20$ pc) of Holberg et. al. 2008. We find that the fraction of bright and young WDs…