Assessing the star formation history of all-sky and part-sky 100 pc white dwarf samples

ABSTRACT Due to Gaia, as well as present and future data from large-scale multi-object spectroscopic follow-up surveys (4MOST, DESI, WEAVE, SDSS-V), it is now possible to build representative and minimally biased samples of the local white dwarf population. Here we analyse several volume-limited 100 pc samples of white dwarfs, constructed from different surveys and studies, to evaluate their completeness and residual biases. We model the underlying star formation history and Galactic disc age via comparison with simulated populations of white dwarfs to quantitatively characterize completeness. We assess whether the benefit of Gaia XP spectra in data sets outweighs the reduction in sample size, and to what extent targeted, part-sky, and magnitude-limited surveys can be used in comparison to all-sky volume-limited surveys. Additionally, we simulate the 4MOST 100PC spectroscopic sub-survey and discuss its use to better understand the local star formation history.