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Related papers: Cool DZ white dwarfs in the SDSS

200 papers

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 into the early ages of each population.…

Aims. We try to identify ultra-cool dwarfs from the seventh Data Release of the Sloan Digital Sky Survey (SDSS DR7) with SDSS i-z and r-z colors. We also obtain proper motion data from SDSS, 2MASS, and UKIDSS and improve spectral typing…

Astrophysics of Galaxies · Physics 2009-08-18 Z. H. Zhang , R. S. Pokorny , H. R. A. Jones , D. J. Pinfield , P. S. Chen , Z. Han , D. Chen , M. C. Gálvez-Ortiz , B. Burningham

We present ugriz photometry and optical spectroscopy for 28 DB and DO white dwarfs with temperatures between 28,000K and 45,000K. About 10 of these are particularly well-observed; the remainder are candidates. These are the hottest DB stars…

We present the identification of 13 DB + dM binaries and 2 DC + dM binaries from the Sloan Digital Sky Survey (SDSS). Before the SDSS only 2 DB + dM binaries and 1 DC + dM binary were known. At least three, possibly 8, of the new DB + dM…

The physical nature of the sdA stars---cool hydrogen-rich objects with spectroscopic surface gravities intermediate between main sequence and canonical mass white dwarfs---has been elusive since they were found in Sloan Digital Sky Survey…

Solar and Stellar Astrophysics · Physics 2018-11-28 Ingrid Pelisoli , Keaton J. Bell , S. O. Kepler , D. Koester

Beyond its goals related to the extragalactic universe, the Sloan Digital Sky Survey (SDSS) is an effective tool for identifying stellar objects with unusual spectral energy distributions. Here we report on the 53 new magnetic white dwarfs…

Astrophysics · Physics 2009-11-10 Gary D. Schmidt

The photospheres of the coolest helium-atmosphere white dwarfs are characterized by fluid-like densities. Under those conditions, standard approximations used in model atmosphere codes are no longer appropriate. Unfortunately, the majority…

Solar and Stellar Astrophysics · Physics 2018-08-29 Simon Blouin , Patrick Dufour , Nicole F. Allard

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 white dwarf stars (DAs) and helium…

We report on efforts to identify large samples of very and extremely metal-poor stars based on medium-resolution spectroscopy and ugriz photometry obtained during the course of the Sloan Digital Sky Survey (SDSS), and its extension,…

Astrophysics · Physics 2009-11-13 Timothy C. Beers , Daniela Carollo

The New Luyten Two-Tenths catalog contains a large number of high-proper motion white dwarf candidates that remain to be spectroscopically confirmed. We present new spectroscopic observations as well as SDSS archival spectra of 49 white…

Astrophysics · Physics 2009-11-11 Adela Kawka , Stephane Vennes

We report the discovery of seven high proper motion stars with proper motions between about 0.7 and 2.2 arcsec/yr. They were detected in an archival search using multi-epoch positions in the optical SuperCOSMOS Sky Surveys and in the…

Astrophysics · Physics 2009-11-10 R. -D. Scholz , I. Lehmann , I. Matute , H. Zinnecker

An extensive sample of M, L and T dwarfs identified in the Sloan Digital Sky Survey (SDSS) has been compiled. The sample of 718 dwarfs includes 677 new objects (629 M dwarfs, 48 L dwarfs) together with 41 that have been previously…

Astrophysics · Physics 2019-08-15 S. L. Hawley , K. R. Covey , G. R. Knapp , D. A. Golimowski , X. Fan

We present the full spectroscopic white dwarf and hot subdwarf sample from the SDSS first data release, DR1. We find 2551 white dwarf stars of various types, 240 hot subdwarf stars, and an additional 144 objects we have identified as…

Little is known about the incidence of magnetic fields among the coolest white dwarfs. Their spectra usually do not exhibit any absorption lines as the bound-bound opacities of hydrogen and helium are vanishingly small. Probing these stars…

Solar and Stellar Astrophysics · Physics 2015-06-24 Mark Hollands , Boris Gaensicke , Detlev Koester

We report the discovery of a new metal-rich DAZ white dwarf, GD 362. High signal-to-noise optical spectroscopy reveals the presence of spectral lines from hydrogen as well as CaI, CaII, MgI, and FeI. A detailed model atmosphere analysis of…

Astrophysics · Physics 2009-11-10 A. Gianninas , P. Dufour , P. Bergeron

We have paired the Second Data Release of the Large Area Survey of the UKIRT Infrared Deep Sky Survey with the Fifth Data Release of the Sloan Digital Sky Survey to identify ten cool white dwarf candidates, from their photometry and…

Astrophysics · Physics 2014-11-18 N. Lodieu , S. K. Leggett , P. Bergeron , A. Nitta

Early data taken during commissioning of the SDSS have resulted in the discovery of a very cool white dwarf. It appears to have stronger collision induced absorption from molecular hydrogen than any other known white dwarf, suggesting it…

We present optical spectroscopy and near-infrared photometry of 57 faint ($g= 19-22$) high proper motion white dwarfs identified through repeat imaging of $\approx3100$ square degrees of the Sloan Digital Sky Survey footprint by Munn et al.…

Solar and Stellar Astrophysics · Physics 2016-09-07 Kyra Dame , A. Gianninas , Mukremin Kilic , Jeffrey A. Munn , Warren R. Brown , Kurtis A. Williams , Ted von Hippel , Hugh C. Harris

We present a catalog of 857 white dwarf (WD)-M binaries from the sixth data release (DR6) of the Sloan Digital Sky Survey (SDSS), most of which were previously identified. For 636 of them, we complete a spectral analysis and derive the…

Astrophysics · Physics 2014-09-16 René Heller , Derek Homeier , Stefan Dreizler , Roy Østensen

Over 1500 DBZ or DZ white dwarfs (WDs) have been observed so far, and polluted atmospheres with metal elements have been found among these WDs. The surface heavy element abundances of known DBZ or DZ WDs show an evolutionary sequence. By…

Solar and Stellar Astrophysics · Physics 2021-10-13 Chunhua Zhu , Helei Liu , Zhaojun Wang , Guoliang Lv