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Related papers: Spectroscopic observations of high proper motion D…

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We report on the spectroscopic confirmation of 68 new bright ($G=13.5-17.2$ mag) and blue (pre-)white dwarfs (WDs). This finding has allowed us to almost double the number of the hottest ($T_{\mathrm{eff}} \geq 60$kK) known WDs brighter…

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…

We present the results of a radial velocity survey designed to measure the fraction of double degenerates among DA white dwarfs. The narrow core of the H-alpha line was observed twice or more for 46 white dwarfs yielding radial velocities…

Astrophysics · Physics 2009-10-31 P. F. L. Maxted , T. R. Marsh

We identify seven new ultracool white dwarfs discovered in the Sloan Digital Sky Survey (SDSS). The SDSS photometry, spectra, and proper motions are presented, and additional BVRI data are given for these and other previously discovered…

We present a 20-pc, volume-limited sample of M7-L8 dwarfs created through spectroscopic follow-up of sources selected from the Two Micron All Sky Survey (2MASS) Second Incremental Release Point Source Catalog. In this paper, we present…

We present a spectroscopic and kinematic analysis of 79 nearby M dwarfs in 77 systems. All are low-proper-motion southern hemisphere objects and were identified in a nearby star survey with a demonstrated sensitivity to young stars. Using…

Solar and Stellar Astrophysics · Physics 2017-05-24 Adric R. Riedel , Munazza K. Alam , Emily L. Rice , Kelle L. Cruz , Todd J. Henry

We present an homogeneous analysis of all DA stars labeled as magnetic in the Montreal White Dwarf Database (MWDD). Our sample is restricted to almost all known magnetic white dwarf showing clear sign of splitting ($B \gtrsim$ 1-2 MG) that…

Solar and Stellar Astrophysics · Physics 2023-02-01 François Hardy , Patrick Dufour , Stefan Jordan

A 2.5 x 100 degree region along the celestial equator (Stripe 82) has been imaged repeatedly from 1998 to 2005 by the Sloan Digital Sky Survey. A new catalogue of ~4 million light-motion curves, together with over 200 derived statistical…

Microlensing events observed in the line of sight toward the LMC indicate that a significant fraction of the mass of the dark halo of the Galaxy is probably composed of white dwarfs. In addition, white dwarf sequences have now be observed…

Astrophysics · Physics 2009-10-31 D. Saumon , S. B. Jacobson

Hydrogen-rich white dwarfs (WDs) comprise the majority of the WD population, but are only rarely found at the very hot end of the WD cooling sequence. A small subgroup that exhibits both hydrogen and helium lines in their spectra, the…

Solar and Stellar Astrophysics · Physics 2024-10-21 Semih Filiz , Klaus Werner , Thomas Rauch , Nicole Reindl

We report the discovery of five very cool white dwarfs in the Sloan Digital Sky Survey (SDSS). Four are ultracool, exhibiting strong collision induced absorption (CIA) from molecular hydrogen and are similar in color to the three previously…

We report on the discovery of the extremely low-mass, hydrogen-rich white dwarf, NLTT 11748. Based on measurements of the effective temperature (8540+/-50 K) and surface gravity (log g = 6.20+/-0.15) obtained by fitting the observed Balmer…

Solar and Stellar Astrophysics · Physics 2015-05-14 A. Kawka , S. Vennes

(Abridged) We present the results of the first unbiased survey for metal pollution among H-atmosphere (DA) white dwarfs with cooling ages of 20-200 Myr and 17000K < Teff < 27000K, using HST COS in the far UV between 1130 and 1435 A. The…

Solar and Stellar Astrophysics · Physics 2014-06-04 Detlev Koester , Boris T. Gänsicke , Jay Farihi

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

Aims: Low-resolution optical spectroscopic observations for 78 very low-mass star and brown dwarf candidates that have been photometrically selected using the DENIS survey point source catalogue. Methods: Spectral types are derived for them…

Solar and Stellar Astrophysics · Physics 2015-05-18 E. L. Martin , N. Phan-Bao , M. Bessell , X. Delfosse , T. Forveille , A. Magazzu , C. Reyle , H. Bouy , R. Tata

The white dwarf luminosity function is an important tool to understand the properties of the Solar neighborhood, like its star formation history, and its age. Here we present a population synthesis study of the white dwarf population within…

Solar and Stellar Astrophysics · Physics 2016-08-06 S. Torres , E. García-Berro

In this paper, we describe how to use the Maximum Reduced Proper Motion method (Phan-Bao et al. 2003) to detect 57 nearby L and late-M dwarfs (d_phot <= 30 pc): 36 of them are newly discovered. Spectroscopic observations of 43 of the 57…

Solar and Stellar Astrophysics · Physics 2015-05-28 N. Phan-Bao

We have conducted a novel search of most of the southern sky for nearby red dwarfs having low proper motions, with specific emphasis on those with proper motion < 0.18 arcsec yr-1, the lower cutoff of Luyten's classic proper motion catalog.…

We present a near-infrared photometric search for unresolved substellar companions and debris disks around white dwarfs in the UKIRT Infrared Deep Sky Survey Large Area Survey. We cross-correlate the SDSS DR4 and McCook & Sion catalogues of…

Solar and Stellar Astrophysics · Physics 2015-05-28 P. R. Steele , M. R. Burleigh , P. D. Dobbie , R. F. Jameson , M. A. Barstow , R. P. Satterthwaite

We report the discovery of 182 new southern stars with proper motion larger than 0.45''/yr. The stars were found in an expansion of the SUPERBLINK proper motion survey to 8,980 square degrees south of Decl.=-30. The new high proper motion…

Astrophysics · Physics 2008-11-26 Sebastien Lepine
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