The White Dwarf Binary Survey (WDB)

Binary systems containing one or two white dwarfs are important for studying stellar evolution and interactions under a wide range of astrophysical conditions. Thanks to the Gaia mission we have identified the first statistically significant and unbiased sample of ~ 170 000 white dwarf binary candidates. It comprises both systems that never interacted that are part of common proper motion pairs and systems that evolved through mass transfer episodes resulting in close white dwarf binaries. White dwarf binaries hold the potential to observationally constrain a wide variety of key ingredients that currently limit the validity of theoretical models.
Published in The Messenger vol. 190, pp. 4-6, March 2023.