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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 followup
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. The
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
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 Observatory
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 have
The Dust Cloud around the White Dwarf G29-38
We present new observations of the white dwarf G29-38 with the camera (4.5 and 8 μm), photometer (24 μm), and spectrograph (5.5-14 μm) of the Spitzer Space Telescope. This star has an exceptionally
Cataclysmic variables from sloan digital sky survey - V. The fifth year (2004)
This paper identifies the cataclysmic variables that appear in spectra obtained in 2004 as part of the Sloan Digital Sky Survey. Spectra of 41 objects, including seven systems that were previously
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 that
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
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 the