J/A+A/419/L5 Masses and radii of DA white dwarfs in SDSS DR1 (Madej+, 2004)
Mass distribution of DA white dwarfs in the First Data Release of the
Sloan Digital Sky Survey.
Madej J., Nalezyty M., Althaus L.G.
<Astron. Astrophys., 419, L5-L8 (2004)>
=2004A&A...419L...5M 2004A&A...419L...5M (SIMBAD/NED BibCode)
ADC_Keywords: Stars, white dwarf ; Stars, masses ; Effective temperatures ;
Stars, diameters
Keywords: catalogs - stars: fundamental parameters - stars: white dwarfs
Abstract:
We investigate the sample of 1175 new nonmagnetic DA white dwarfs with
the effective temperatures Teff≥12000K, which were extracted from
the Data Release 1 of the Sloan Digital Sky Survey. We determined
masses, radii, and bolometric luminosities of stars in the sample. The
above parameters were derived from the effective temperatures Teff
and surface gravities logg published in the DR1, and the new
theoretical M-R relations for carbon-core and oxygen-core white
dwarfs. Mass distribution of white dwarfs in this sample exhibits the
peak at M=0.562M☉ (carbon-core stars), and the tail towards
higher masses. Both the shape of the mass distribution function and
the empirical mass-radius relation are practically identical for white
dwarfs with either pure carbon or pure oxygen cores.
Description:
We determined masses, radii and bolometric luminosities for a sample
of new DA white dwarfs extracted from the Data Release 1 of the Sloan
Digital Sky Survey. Masses and radii of isolated stars were estimated
from the effective temperatures, Teff, and surfaces gravities, log g,
which were previously determined from the best fits to theoretical
pure H model atmosphere spectra (Kleinman et al., 2004, Cat.
J/ApJ/607/426). We used mass-radius relation obtained from the
evolutionary sequences for white dwarfs with carbon and oxygen core +
thin H envelope by Panei, Althaus and Benvenuto (2000A&A...353..970P 2000A&A...353..970P).
Masses, radii and luminosities were determined for 1833 DA white
dwarfs. Additionally, these parameters were evaluated for 86 white
dwarfs of the lowest masses assuming pure He core + thin H envelope.
Note, that probably values of log g determined for stars of
Teff<12000K are systematically larger than for hotter stars due to
uncertain paramerization of convection in white dwarf atmospheres.
Data are collected in three files, for white dwarfs consisting of pure
carbon core (file table1.dat), pure oxygen core (table2.dat) and pure
helium core (table3.dat) surrounded by a thin hydrogen layer. Each row
in a file shows the SDSS DR1 star designation, the effective
temperature Teff, logarithm of surface gravity logg, mass M in solar
masses, radius R in kilometers, bolometric luminosity and their
errors.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 101 1833 *Data assuming Carbon core + H envelope
table2.dat 101 1833 *Data assuming Oxygen core + H envelope
table3.dat 101 86 *Data assuming Helium core + H envelope
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Note on table*.dat: stars in the tables are listed according to growing Teff.
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Byte-by-byte Description of file: table1.dat table2.dat table3.dat
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Bytes Format Units Label Explanations
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2- 25 A24 --- WD SDSS DR1 designation of the star
28- 33 F6.0 K Teff Effective temperature
35- 39 F5.0 K e_Teff Error of the effective temperature
43- 46 F4.2 [cm/s2] logg Logarithm of surface gravity
48- 51 F4.2 [cm/s2] e_logg Error of the logarithm of surface gravity
55- 59 F5.3 Msun M White dwarf mass (1)
61- 65 F5.3 Msun e_M Error of the white dwarf mass (1)
68- 73 F6.0 km R White dwarf radius in kilometers
76- 80 F5.0 km e_R Error of the white dwarf radius
83- 91 E9.3 Lsun L White dwarf bolometric luminosity (2)
94-101 E8.2 Lsun e_L Error of the white dwarf luminosity (2)
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Note (1): Msun = 1.989x10+30 kg
Note (2): Lsun = 3.826x10+26 W
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Acknowledgements:
Jerzy Madej, jm(at)astrouw.edu.pl, University of Warsaw
(End) Patricia Vannier [CDS] 25-Jan-2019