293 datasets found

We present ugriz photometry and optical spectroscopy for 28 DB and DO white dwarfs with temperatures between 28000 and 45000K. About 10 of these are particularly well observed;...

We present the kinematical properties, distribution of spectroscopic subtypes, and stellar population subcomponents of the white dwarfs within 20pc of the Sun. We find no...

Using recent photometric calibrations, we develop greatly improved distance estimates for DA white dwarfs using multi-band synthetic photometry based on spectroscopic...

We have conducted a detailed new survey of the local population of white dwarfs lying within 20pc of the Sun. A new revised catalog of local white dwarfs containing 122 entries...

We present the latest catalog of more than 1200 spectroscopically selected close binary systems observed with the Sloan Digital Sky Survey through Data Release Five. We use the...

We present the culmination of our near-infrared survey of the optically spectroscopically identified white dwarf stars from the McCook and Sion (1999ApJS..121....1M, see Cat. )...

We present spectra for 33 previously unclassified white dwarf systems brighter than V=17, primarily in the southern hemisphere. Of these new systems, 26 are DA, 4 are DC, 2 are...

We have calibrated four major ground-based photometric systems with respect to the Hubble Space Telescope (HST) absolute flux scale, which is defined by Vega and four...

A reduced proper motion diagram utilising Sloan Digital Sky Survey (SDSS) photometry and astrometry and USNO-B plate astrometry is used to separate cool white dwarf candidates...

We present a spectroscopic sample of 746 detached close binary systems from the Sloan Digital Sky Survey (SDSS) Fourth Data Release (2006ApJS..162...38A). The majority of these...

Fifty-two magnetic white dwarfs have been identified in spectroscopic observations from the Sloan Digital Sky Survey (SDSS) obtained between mid-2002 and the end of 2004,...

We investigate the relationship between age and chromospheric activity for 139 M dwarf stars in wide binary systems with white dwarf companions. We present the measured radial...

We investigate the use of a narrowband DDO51 filter for photometric identification of cool white dwarfs. We report photometric observations of 30 known cool white dwarfs with...

We have previously conducted a search for X-ray sources coincident with white dwarfs using the white dwarf catalog compiled by McCook & Sion (1999, Cat. , ) and the ROSAT...

An initial assessment is made of white dwarf and hot subdwarf stars observed in the Sloan Digital Sky Survey. In a small area of sky (190 square degrees), observed much like the...

Inspired by the hard X-ray emission from WD 2226-210, the central star of the Helix Nebula, we have made a systematic search for similar sources by correlating the white dwarf...

We present UBV color-magnitude diagrams (CMDs) for the globular cluster M4. The CMDs show a sequence of four luminous blue stars (V<20, U-V<-0.6), which appear to be...

Radial velocities and complete space motions were measured for 116 white dwarf stars with M dwarf companions (WD+M), including thirteen pairs having "halo-like" velocities....

The third Gaia Data Release has provided the astronomical community with astrometric data of more than 1.8 billion sources, and low resolution spectra for 220 million. Such a...

Mergers of double white dwarfs (DWDs) are considered significant potential progenitors of type Ia supernovae (SNe Ia), which serve as "standard candles" in cosmology to measure...