J/MNRAS/482/5222 DA and DB white dwarfs properties in Gaia DR2 (Tremblay+, 2019)
Fundamental parameter accuracy of DA and DB white dwarfs in Gaia Data Release 2.
Tremblay P.-E., Cukanovaite E., Gentile Fusillo N.P., Cunningham T.,
Hollands M.A.
<Mon. Not. R. Astron. Soc., 482, 5222-5232 (2019)>
=2019MNRAS.482.5222T 2019MNRAS.482.5222T (SIMBAD/NED BibCode)
ADC_Keywords: Surveys ; Parallaxes, trigonometric ; Parallaxes, spectroscopic ;
Stars, fundamental ; Stars, white dwarf
Keywords: surveys - parallaxes - stars: fundamental parameters - white dwarfs
Abstract:
We report on a comparison of spectroscopic analyses for hydrogen (DA)
and helium atmosphere (DB) white dwarfs with Gaia Data Release 2 (DR2)
parallaxes and photometry. We assume a reddening law and a mass-radius
relation to connect the effective temperatures (Teff) and surface
gravities (logg) to masses and radii. This allows the comparison of
two largely independent sets of fundamental parameters for 7039 DA and
521 DB stars with high-quality observations. This subset of the Gaia
white dwarf sample is large enough to detect systematic trends in the
derived parameters. We find that spectroscopic and photometric
parameters generally agree within uncertainties when the expectation
of a single star is verified. Gaia allows the identification of a
small systematic offset in the temperature scale between the two
techniques, as well as confirming a small residual high-mass bump in
the DA mass distribution around 11000-13000K. This assessment of the
accuracy of white dwarf fundamental parameters derived from Gaia is a
first step in understanding systematic effects in related
astrophysical applications such as the derivation of the local stellar
formation history, initial-to-final mass relation, and statistics of
evolved planetary systems.
Description:
The all-sky and bright sample of DA white dwarfs from Gianninas et al.
(2011ApJ...743..138G 2011ApJ...743..138G, Cat. J/ApJ/743/138) drawn from the White Dwarf
Catalogue of McCook & Sion (1999ApJS..121....1M 1999ApJS..121....1M, Cat. III/210) is a
benchmark to study their fundamental parameters because of the
high-signal-to-noise ratio (S/N) of the spectroscopic observations.
The relative proximity of the objects also allows for the most precise
Gaia data set that we employ in this study. We rely on the 1D
atmospheric parameters as published by the authors. We also use a
sample of DA white dwarfs drawn from the Gaia-SDSS catalogue of
Gentile Fusillo et al. (2019MNRAS.482.4570G 2019MNRAS.482.4570G, Cat. J/MNRAS/482/4570).
We have secured all spectra from the SDSS SkyServer with the new data
reduction from DR14 (Abolfathi et al. 2018ApJS..235...42A 2018ApJS..235...42A), and fitted
the observations using the same technique and 1D model atmospheres as
those employed for our analyses of earlier data releases (Tremblay,
Bergeron & Gianninas 2011ApJ...730..128T 2011ApJ...730..128T, Cat. J/ApJ/730/128; Tremblay
et al. 2016MNRAS.461.2100T 2016MNRAS.461.2100T) as well as Gianninas et al.
(2011ApJ...743..138G 2011ApJ...743..138G, Cat. J/ApJ/743/138).
Fitted spectroscopic parameters of Gaia-SDSS DR1-DR7 DA white dwarfs
and Gaia-SDSS-III DR7-DR14 DA white dwarfs are presented in table A1
and A2 respectively.
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
tablea1.dat 118 2726 Subsample of Gaia-SDSS DR1-DR7 DA white dwarfs
tablea2.dat 118 3168 Subsample of Gaia-SDSS-III (BOSS) DR9-DR14 DA
white dwarfs
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See also:
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
II/294 : The SDSS Photometric Catalog, Release 7 (Adelman-McCarthy+, 2009)
Byte-by-byte Description of file: tablea1.dat tablea2.dat
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Bytes Format Units Label Explanations
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1- 24 A24 --- Name SDSS Name (SDSS JHHMMSS.ss+DDMMSS.s)
26- 40 A15 --- MPF SDSS MJD-plate-fiber ID
42- 49 F8.5 mas plx Gaia parallax
51- 57 F7.5 mas e_plx Error on plx
59- 64 I6 K Teff 3D Effective temperature (1)
66- 70 I5 K e_Teff Error on Teff (1)
72- 76 F5.3 --- logg 3D Surface gravity (1)
78- 82 F5.3 --- e_logg Error on logg (1)
84- 91 F8.5 --- plxsp 3D Spectroscopic parallax (de-reddened) (1)
93-100 F8.5 --- e_plxsp Error on plxsp (1)
102-118 A17 --- Comment Comment on the model used for the Balmer line
fitting (2)
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Note (1): Atmospheric parameters are from Balmer line fitting
Note (2): Comments as follows:
models with C/N/O = Objects fitted with models including CNO
(Gianninas et al. 2010ApJ...720..581G 2010ApJ...720..581G)
fixed Teff = Effective temperature fixed for the fitting
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History:
From electronic version of the journal
(End) Ana Fiallos [CDS] 01-Jul-2022