NEAR-ULTRAVIOLET AND OPTICAL EFFECTS OF DEBRIS DISKS AROUND WHITE DWARFS

ABSTRACT We use 1837 DA white dwarfs with high signal-to-noise ratio spectra and Gaia parallaxes to verify the absolute calibration and extinction coefficients for the Galaxy Evolution Explorer (GALEX). We use white dwarfs within 100 pc to verify the linearity correction to the GALEX data. We find that the linearity correction is valid for magnitudes brighter than 15.95 and 16.95 for the far-ultraviolet (FUV) and near-ultraviolet (NUV) bands, respectively. We also use DA white dwarfs beyond 250 pc to calculate extinction coefficients in the FUV and NUV bands: RFUV = 8.01 ± 0.07 and RNUV = 6.72 ± 0.04. These are consistent with the predicted extinction coefficients for Milky Way-type dust in the FUV, but smaller than predictions in the NUV. With well understood optical spectra and state-of-the-art model atmosphere analysis, these white dwarfs currently provide the best constraints on the extinction coefficients for the GALEX data.

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White dwarfs with unresolved substellar companions and debris disks in the UKIDSS Survey

Journal of Physics Conference Series ◽

10.1088/1742-6596/172/1/012058 ◽

2009 ◽

Vol 172 ◽

pp. 012058 ◽

Cited By ~ 2

Author(s):

Paul Steele ◽

Matt Burleigh ◽

Martin Barstow ◽

Richard Jameson ◽

Paul Dobbie

Keyword(s):

White Dwarfs ◽

Debris Disks ◽

Substellar Companions

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THE FREQUENCY OF DEBRIS DISKS AT WHITE DWARFS

The Astrophysical Journal ◽

10.1088/0004-637x/760/1/26 ◽

2012 ◽

Vol 760 (1) ◽

pp. 26 ◽

Cited By ~ 55

Author(s):

Sara D. Barber ◽

Adam J. Patterson ◽

Mukremin Kilic ◽

S. K. Leggett ◽

P. Dufour ◽

...

Keyword(s):

White Dwarfs ◽

Debris Disks

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Non-LTE Model Spectra for Gaseous Planetary Debris Disks around WDs

Proceedings of the International Astronomical Union ◽

10.1017/s1743921313008867 ◽

2013 ◽

Vol 8 (S299) ◽

pp. 342-343

Author(s):

Stephan Hartmann ◽

Thorsten Nagel ◽

Thomas Rauch ◽

Klaus Werner

Keyword(s):

Accretion Disk ◽

Effective Temperature ◽

Surface Density ◽

White Dwarfs ◽

Debris Disks ◽

Chemical Mixture ◽

Dust Disks ◽

Infrared Triplet ◽

Do So

AbstractMetal-rich dust disks around white dwarfs are thought to be the debris of tidally disrupted rocky bodies. While normally the number of features to study the planetary material directly is very limited, ancillary gas disks around some of these white dwarfs provide the opportunity to do so. We used our Tübingen Accretion Disk code AcDc, assuming non-LTE conditions, to model the gaseous spectrum component. We investigated the chemical mixture as well as the surface density and effective temperature, and utilized the Ca ii infrared triplet to determine the geometry of the disk.

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