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White dwarf mass distribution in the SDSS
We determined masses for the 7167 DA and 507 DB white dwarf stars classified as single and non-magnetic in Data Release 4 of the Sloan Digital Sky Survey (SDSS). We obtained revised T eff and log g
We present a new catalog of spectroscopically confirmed white dwarf stars from the Sloan Digital Sky Survey (SDSS) Data Release 7 spectroscopic catalog. We find 20,407 white dwarf spectra,
An independent method for determining the age of the universe
An age of 9.3 + or - 2.0 Gyr is derived for the Galactic disk on the basis of comparisons between the sudden drop in the observed luminosity distribution and theoretical evolutionary white dwarf
New white dwarf and subdwarf stars in the Sloan Digital Sky Survey Data Release 12
White dwarfs carry information on the structure and evolution of the Galaxy, especially through their luminosity function and initial-to-final mass relation. Very cool white dwarfs provide insight
New white dwarf stars in the Sloan Digital Sky Survey Data Release 10
We report the discovery of 9 089 new spectroscopically confirmed white dwarfs and subdwarfs in the Sloan Digital Sky Survey Data Release 10. We obtain Teff, log g and mass for hydrogen atmosphere
Toward ensemble asteroseismology of ZZ Ceti stars with fully evolutionary models
ZZ Ceti stars form the most numerous group of degenerate variable stars. They are otherwise normal DA (H-rich atmospheres) white dwarfs that exhibit pulsations. Here, we present an
DB white dwarfs in the Sloan Digital Sky Survey Data Release 10 and 12
White dwarfs with helium-dominated atmospheres comprise approximately 20% of all white dwarfs. Among the open questions are the total masses and the origin of the hydrogen traces observed in a large
Asteroseismology of the DOV star PG 1159 - 035 with the Whole Earth Telescope
Results are reported from 264.1 hr of nearly continuous time-series photometry on the pulsating prewhite dwarf star (DPV) PG 1159 - 035. The power spectrum of the data set is completely resolved into
New evolutionary sequences for hot h-deficient white dwarfs on the basis of a full account of progenitor evolution
We present full evolutionary calculations appropriate for the study of hot hydrogen-deficient DO white dwarfs, PG 1159 stars, and DB white dwarfs. White dwarf sequences are computed for a wide range
Magnetic white dwarf stars in the Sloan Digital Sky Survey
To obtain better statistics on the occurrence of magnetism among white dwarfs, we searched the spectra of the hydrogen atmosphere white dwarf stars (DAs) in the Data Release 7 of the Sloan Digital