J/ApJ/885/74 1340 Helium rich white dwarfs in the Gaia era (Coutu+, 2019)
Analysis of Helium-rich white dwarfs polluted by heavy elements in the Gaia era.
Coutu S., Dufour P., Bergeron P., Blouin S., Loranger E., Allard N.F.,
Dunlap B.H.
<Astrophys. J., 885, 74 (2019)>
=2019ApJ...885...74C 2019ApJ...885...74C
ADC_Keywords: Stars, white dwarf; Abundances; Spectral types; Stars, masses;
Effective temperatures; Photometry, UBVRI
Keywords: White dwarf stars
Abstract:
We present an analysis of 1023 DBZ/DZ(A) and 319 DQ white dwarf stars
taken from the Montreal White Dwarf Database. This represents a
significant increase over the previous comprehensive studies on these
types of objects. We use new trigonometric parallax measurements from
the Gaia second data release, together with photometry from the Sloan
Digital Sky Survey, Pan-STARRS, Gaia, or BVRI from the literature,
which allow the determination of the mass for the majority of the
objects in our sample. We use the photometric and spectroscopic
techniques with our recently improved model atmospheres code, which
include high-density effects, to accurately determine the effective
temperature, surface gravity, and heavy-element abundances for each
object. We study the abundance of hydrogen in DBZ/DZ white dwarfs and
the properties of the accreted planetesimals. We explore the nature of
the second sequence of DQ stars using proper motions from Gaia and
highlight evidence of crystallization in massive DQ stars. We also
present mass distributions for both spectral types. Finally, we
discuss the implications of our findings in the context of the
spectral evolution of white dwarfs and provide the atmospheric
parameters for each star.
Description:
We selected our objects from the Montreal White Dwarf Database (MWDD).
All objects in our sample were then cross-matched with Gaia DR2 to
retrieve photometric and astrometric data.
We cross-matched our sample with Pan-STARRS DR1 and SDSS DR14 to
retrieve grizy and ugriz point-spread function magnitudes,
respectively. When SDSS ugriz is not available for an object, we rely
on Pan-STARRS data, previously published BVRI photometry, or simply
Gaia broadband photometry, in that order of priority. For J0739+0513
(Procyon B), we rely on Hubble Space Telescope (HST) photometry.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 83 1340 Object names, spectral types, and coordinates
table4.dat 79 1023 Atmospheric parameters for DZ stars
table5.dat 84 317 Atmospheric parameters for DQ stars
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See also:
B/simbad : Simbad objects catalogue (M.Wenger 2000)
I/311 : Hipparcos, the New Reduction (van Leeuwen, 2007)
I/337 : Gaia DR1 (Gaia Collaboration, 2016)
II/345 : Gaia DR2 (Gaia Collaboration, 2018)
J/ApJS/133/413 : BVRIJHK photometry of cool white dwarfs (Bergeron+, 2001)
J/ApJS/147/145 : IUE low-dispersion spectra of white dwarfs (Holberg+, 2003)
J/ApJ/607/426 : Catalog of white dwarfs in SDSS-DR1 (Kleinman+, 2004)
J/AJ/132/676 : SDSS hot DB white dwarfs (Eisenstein+, 2006)
J/AJ/132/1221 : VJHK and SDSS photometry of DA white dwarfs (Holberg+, 2006)
J/ApJ/663/1291 : DZ stars in SDSS DR4 (Dufour+, 2007)
J/AJ/134/252 : New nearby white dwarf systems (Subasavage+, 2007)
J/A+A/470/1079 : UVES/VLT spectra of white dwarfs (Voss+, 2007)
J/ApJ/765/12 : Carbon stars & DQ white dwarfs from SDSSDR7+DR8 (Green,2013)
J/ApJS/204/5 : SDSS DR7 white dwarf catalog (Kleinman+, 2013)
J/AJ/145/136 : Astrometry & photometry nearby white dwarfs (Limoges+, 2013)
J/MNRAS/446/4078 : New white dwarf stars in SDSS DR10 (Kepler+, 2015)
J/ApJS/219/19 : Census nearby white dwarfs from SUPERBLINK (Limoges+, 2015)
J/MNRAS/455/3413 : New white dwarf & subdwarf stars in SDSS DR12 (Kepler+,2016)
J/MNRAS/467/4970 : Cool DZ white dwarfs. I. (Hollands+, 2017)
J/A+A/616/A10 : 46 open clusters GaiaDR2 HRdiagrams (Gaia Collaboration,2018)
J/ApJS/239/26 : NOFS astrometric measurements distant WDs (Leggett+, 2018)
J/ApJ/878/63 : Cool WD atmosphere models.IV. Spectral evol. (Blouin+, 2019)
J/MNRAS/482/4570 : Gaia DR2 white dwarf candidates (Gentile Fusillo+, 2019)
J/A+A/628/A102 : Carbon-rich (DQ) white dwarfs in SDSS (Koester+, 2019)
http://www.montrealwhitedwarfdatabase.org/ : Montreal White Dwarf Database
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- Name Object name
12- 30 I19 --- Gaia ? Gaia DR2 Source identifier
32- 57 A26 --- MWDD Montreal White Dwarf Database identifier
59- 63 A5 --- SpT Spectral Type
65- 73 F9.5 deg RAdeg [0.04/360] Right Ascension (J2000)
75- 83 F9.5 deg DEdeg [-64.9/78.4] Declination (J2000)
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- Name Object name
12- 16 I5 K Teff [4132/15794] Effective temperature
18- 21 I4 K e_Teff [28/6173] Error in Teff
23- 26 F4.2 [cm/s2] logg [7.08/8.95] Log of the surface gravity
28- 31 F4.2 [cm/s2] e_logg [0.02/1.6]? Lower error in logg
33- 36 F4.2 [cm/s2] E_logg [0.02/2.49]? Higher error in logg
38- 41 F4.2 Msun Mass [0.21/1.16]? Mass
43- 46 F4.2 Msun e_Mass [0.02/0.47]? Lower error in Mass
48- 51 F4.2 Msun E_Mass [0.02/1.18]? Higher error in Mass
53- 58 F6.2 [-] [H/He] [-30/-3] Log of the H/He ratio
60- 63 F4.2 [-] e_[H/He] [0/1.83]? Error in logH/He
65- 69 F5.1 pc Dist [4.3/818.8] Distance of the object
71- 75 F5.1 pc e_Dist [0/633.9] Error in Dis
77 A1 --- f_[H/He] Flag on logH/He (1)
79 A1 --- f_Dist Flag on Dist (2)
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Note (1): Flag as follows:
1 = [H/He] is fixed rather than fitted (918 occurrences).
Note (2): Flag as follows:
1 = Dist is a photometric distance based on the value of
logg=8 in the absence of a parallax (344 occurrences).
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- Name Object name
12- 16 I5 K Teff [6004/15167] Effective temperature
18- 21 I4 K e_Teff [33/1164] Error in Teff
23- 26 F4.2 [cm/s2] logg [7.01/8.97] Log of the surface gravity
28- 31 F4.2 [cm/s2] e_logg [0.02/0.62]? Lower error in logg
33- 36 F4.2 [cm/s2] E_logg [0.02/0.89]? Higher error in logg
38- 41 F4.2 Msun Mass [0.18/1.17]? Mass
43- 46 F4.2 Msun e_Mass [0.01/0.25]? Lower error in Mass
48- 51 F4.2 Msun E_Mass [0.01/0.51]? Higher error in Mass
53- 57 F5.2 [-] [C/He] [-7.29/-1.14] Log of the C/He ratio
59- 62 F4.2 [-] e_[C/He] [0.01/0.77]? Error in [C/He]
64- 68 F5.2 [-] [H/He] [-3/-3]? Log of the H/He ratio
70- 74 F5.1 pc Dist [3.5/511.5] Distance
76- 80 F5.1 pc e_Dist [0/166] Uncertainty in Dist
82- 82 A1 --- f_[H/He] Flag on [H/He] (1)
84- 84 A1 --- f_Dist Flag on Dist (2)
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Note (1): Flag as follows:
1 = [H/He] is fixed rather than fitted (11 occurrences).
Note (2): Flag as follows:
1 = Dist is a photometric distance based on the value of
logg=8 in the absence of a parallax (14 occurrences).
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 03-Jun-2021