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

TL;DR

This study evaluates the completeness and biases of local white dwarf samples from various surveys, modeling star formation history and disc age using Gaia data and simulations to improve understanding of the Milky Way's evolution.

Contribution

It introduces a comprehensive analysis of 100pc white dwarf samples from multiple surveys, assessing their biases and the effectiveness of Gaia spectra in star formation history studies.

Findings

Gaia XP spectra offer benefits that may outweigh sample size reduction.

Simulated 4MOST 100PC sub-survey helps constrain local star formation history.

Different survey types vary in completeness and bias, affecting their utility for Galactic studies.

Abstract

Thanks to Gaia and large-scale 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 100pc 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 characterise completeness. We assess whether the benefit of Gaia XP spectra in datasets 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 sub-survey and discuss its use to better understand the local star formation history.