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Metal traces in white dwarfs of the SPY (ESO Supernova Ia Progenitor Survey) sample
We search for faint Ca II lines in the spectra of about 800 apparently single white dwarfs observed at high resolution for the SPY (ESO Supernova Progenitor Survey) survey. Photospheric Ca isExpand
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HS 0146+1847 : a DAZB white dwarf of very unusual composition
HS 0146+1847, originally identified as a white dwarf candidate in proper motion surveys, was rediscovered as a candidate in the Hamburg Quasar Survey. Spectra obtained for the SPY (ESO Supernova laExpand
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ANCIENT PLANETARY SYSTEMS ARE ORBITING A LARGE FRACTION OF WHITE DWARF STARS
Infrared studies have revealed debris likely related to planet formation in orbit around ~30% of youthful, intermediate mass, main-sequence stars. We present evidence, based on atmospheric pollutionExpand
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DA white dwarfs in Sloan Digital Sky Survey Data Release 7 and a search for infrared excess emission
We present a method which uses colour–colour cuts on the Sloan Digital Sky Survey (SDSS) photometry to select white dwarfs with hydrogen-rich (DA) atmospheres without the recourse to spectroscopy.Expand
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The Chemical Composition of an Extrasolar Minor Planet
We report the relative abundances of 17 elements in the atmosphere of the white dwarf star GD 362, material that, very probably, was contained previously in a large asteroid or asteroids withExpand
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A METAL-RICH LOW-GRAVITY COMPANION TO A MASSIVE MILLISECOND PULSAR
Most millisecond pulsars with low-mass companions are in systems with either helium-core white dwarfs or non-degenerate ("black widow" or "redback") stars. A candidate counterpart to PSR J1816+4510Expand
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CHEMICAL ABUNDANCES IN THE EXTERNALLY POLLUTED WHITE DWARF GD 40: EVIDENCE OF A ROCKY EXTRASOLAR MINOR PLANET
We present Keck/High Resolution Echelle Spectrometer data with model atmosphere analysis of the helium-dominated polluted white dwarf GD 40, in which we measure atmospheric abundances relative toExpand
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Thirty-Five New Pulsating Da White Dwarf Stars
We present 35 new pulsating DA (hydrogen atmosphere) white dwarf stars discovered from the Sloan Digital Sky Survey (SDSS) and the Hamburg Quasar Survey (HQS). We have acquired high-speed time seriesExpand
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A precision study of two eclipsing white dwarf plus M dwarf binaries
TLDR
We use a combination of X-shooter spectroscopy, ULTRACAM high-speed photometry and SOFI near-infrared photometry to measure the masses and radii of both components of the eclipsing post common envelope binaries SDSSJ121258.25-012310.1 and GKVir. Expand
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The stellar content of the hamburg/eso survey. I. automated selection of da white dwarfs
We describe automatic procedures for the selection of DA white dwarfs in the Hamburg/ESO objective-prism survey (HES). For this purpose, and the selection of other stellar objects (e.g., metal-poorExpand
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