A White Dwarf catalogue from Gaia-DR2 and the Virtual Observatory
Abstract
(See http://cdsads.u-strasbg.fr/abs/2018MNRAS.480.4505J)We present a catalogue of 73,221 white dwarf candidates extracted from the astrometric and photometric data of the recently published Gaia-DR2 catalogue. White dwarfs were selected from the Gaia Hertzsprung-Russell diagram with the aid of the most updated population synthesis simulator.Our analysis shows that Gaia has virtually identified all white dwarfs within 100 pc from the Sun. Hence; our sub-population of 8555 white dwarfs within this distance limit and the colour range considered; -0.52<(GBP-GRP)<0.80; is the largest and most complete volume-limited sample of such objects to date. From this sub-sample; we identified 8,343 CO-core and 212 ONe-core white dwarf candidates and derived a white dwarf space density of 4.9± 0.4 x 10-3 pc-3. A bifurcation in the Hertzsprung-Russell diagram for these sources; which our models do not predict; is clearly visible.We used the Virtual Observatory SED Analyzer tool to derive effective temperatures and luminosities for our sources by fitting their spectral energy distributions; that we built from the ultraviolet to the near-infrared using publicly available photometry through the Virtual Observatory. From these parameters; we derived the white dwarf radii. Interpolating the radii and effective temperatures in hydrogen-rich white dwarf cooling sequences; we derived the surface gravities and masses.The Gaia 100 pc white dwarf population is clearly dominated by cool ( 8,000 K) objects and reveals a significant population of massive (M 0.8 Solar Mass) white dwarfs; of which no more than 30-40 per cent can be attributed to hydrogen-deficient atmospheres; and whose origin remains uncertain.
- Publication:
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The Gaia Universe
- Pub Date:
- April 2019
- DOI:
- 10.5281/zenodo.3236164
- Bibcode:
- 2019gaia.confE..48J
- Keywords:
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- Zenodo community eslab53