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

Understand

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 is anomalously high among the WDs detected in multiple systems with main sequence (MS) companions compared to that of the single WDs and theoretical expectations.