The Gaia 20 pc white dwarf sample

Abstract

Using Gaia DR2 data, we present an up-to-date sample of white dwarfs within\n20 pc of the Sun. In total we identified 139 systems in Gaia DR2, nine of which\nare new detections, with the closest of these located at a distance of 13.05\npc. We estimated atmospheric parameters for all stellar remnants based on the\nGaia parallaxes and photometry. The high precision and completeness of the Gaia\nastrometry allowed us to search for wide binary companions. We re-identified\nall known binaries where both components have accurate DR2 astrometry, and\nestablished the binarity of one of the nine newly identified white dwarfs. No\nnew companions were found to previously known 20 pc white dwarfs. Finally, we\nestimated the local white dwarf space-density to be\n$(4.49\\pm0.38)\\times10^{-3}$ pc$^{-3}$, having given careful consideration to\nthe distance-dependent Gaia completeness, which misses known objects at short\ndistances, but is close to complete for white dwarfs near 20 pc.\n