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The White Dwarf Luminosity Function from Sloan Digital Sky Survey Imaging Data
A sample of white dwarfs is selected from SDSS DR3 imaging data using their reduced proper motions, based on improved proper motions from SDSS plus USNO-B combined data. Numerous SDSS and followupExpand
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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 dwarfExpand
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Evolutionary models for pulsation studies of white dwarfs
A large grid of equilibrium models suitable for adiabatic and nonadiabatic seismological investigations of pulsating white dwarfs of the DAV and DBV types is presented and discussed in detail. TheExpand
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A GRAVITATIONAL REDSHIFT DETERMINATION OF THE MEAN MASS OF WHITE DWARFS. DA STARS
We measure apparent velocities (v app) of the Hα and Hβ Balmer line cores for 449 non-binary thin disk normal DA white dwarfs (WDs) using optical spectra taken for the European Southern ObservatoryExpand
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A new class of pulsating white dwarf of extremely low mass: The fourth and fifth members
We report the discovery of two new pulsating extremely low-mass (ELM) white dwarfs (WDs), SDSS J161431.28+191219.4 (hereafter J1614) and SDSS J222859.93+362359.6 (hereafter J2228). Both WDs haveExpand
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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 intoExpand
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Two planets orbiting the recently formed post-common envelope binary NN Serpentis
Planets orbiting post-common envelope binaries provide fundamental information on planet formation and evolution. We searched for such planets in NN Ser ab, an eclipsing short-period binary thatExpand
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SDSS J184037.78+642312.3: The First Pulsating Extremely Low Mass White Dwarf
We report the discovery of the first pulsating extremely low mass (ELM) white dwarf (WD), SDSS J184037.78+642312.3 (hereafter J1840). This DA (hydrogen-atmosphere) WD is by far the coolest and theExpand
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Discovery of pulsations, including possible pressure modes, in two new extremely low mass, He-core white dwarfs
We report the discovery of the second and third pulsating extremely low mass white dwarfs (WDs), SDSS J111215.82+111745.0 (hereafter J1112) and SDSS J151826.68+065813.2 (hereafter J1518). Both haveExpand
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A Spitzer White Dwarf Infrared Survey
We present mid-infrared photometry of 124 white dwarf stars with the Spitzer Space Telescope. Objects were observed simultaneously at 4.5 and 8.0 μm with sensitivities better than 0.1 mJy. This dataExpand
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