Related papers: Exomoons as sources of white dwarf pollution
We utilize observations of 16 white dwarf stars to calculate and analyze the oxidation states of the parent bodies accreting onto the stars. Oxygen fugacity, a measure of overall oxidation state for rocks, is as important as pressure and…
Polluted white dwarfs are generally accreting terrestrial-like material that may originate from a debris belt like the asteroid belt in the solar system. The fraction of white dwarfs that are polluted drops off significantly for white…
Metal pollution in white dwarf photospheres originates from the accretion of some combination of planets, moons, asteroids, comets, boulders, pebbles and dust. When large bodies reside in dynamically stagnant locations -- unable themselves…
Approximately 25-50% of white dwarfs (WDs) exhibit metal absorption lines in their photospheres, which are attributed to accretion from their remnant planetary systems. Although white dwarfs with detected planetary systems are more likely…
Approximately 25--50\% of white dwarfs (WDs) exhibit metal absorption lines in their photospheres, interpreted as evidence of ongoing/recent accretion of planetary debris from remnant systems. Previous theoretical studies have suggested…
The majority of stars both host planetary systems and evolve into a white dwarf (WD). To understand their post-main-sequence (PMS) planetary system evolution, we present a search for transiting/eclipsing planets and other Substellar Bodies…
Prior studies have hypothesized that some polluted white dwarfs record continent-like granitic crust--which is abundant on Earth and perhaps uniquely indicative of plate tectonics. But these inferences derive from only a few elements, none…
Metal pollution in white dwarf atmospheres is likely to be a signature of remnant planetary systems. Most explanations for this pollution predict a sharp decrease in the number of polluted systems with white dwarf cooling age. Observations…
Previously published observations of 60 externally-polluted white dwarfs show that none of the stars have accreted from intact refractory-dominated parent bodies composed mainly of Al, Ca and O, although planetesimals with such a…
A large proportion of observed white dwarfs (WDs) show evidence of debris disks, remnants of the former planetary systems, and/or signatures of heavy elements in their atmospheres, induced by the accretion of planetary matter onto their…
The polluted white dwarf (WD) system SDSS J122859.93+104032.9 (SDSS J1228) shows variable emission features interpreted as originating from a solid core fragment held together against tidal forces by its own internal strength, orbiting…
Many white dwarfs have accreted material from their own planetary systems. These objects can be used to infer the composition of exoplanetary material and identify evidence for key geological processes. However, the white dwarf atmospheric…
White dwarf stars frequently experience external pollution by heavy elements, and yet the intrinsically carbon-enriched DQ spectral class members fail to exhibit this phenomenon, representing a decades-old conundrum. This study reports a…
Although there is abundant and diverse observational evidence in support of white dwarf stars hosting planets or debris disks which form in the catastrophic destruction of various planetary bodies, the key processes that explain these…
White dwarfs (WDs) polluted by exoplanetary material provide the unprecedented opportunity to directly observe the interiors of exoplanets. However, spectroscopic surveys are often limited by brightness constraints, and WDs tend to be very…
We present evidence that excesses in Be in polluted white dwarfs (WDs) are the result of accretion of icy exomoons that formed in the radiation belts of giant exoplanets. Here we use excess Be in the white dwarf GALEX J2339-0424 as an…
Recent studies have shown that large exomoons can form in the accretion disks around super-Jovian extrasolar planets. These planets are abundant at about 1 AU from Sun-like stars, which makes their putative moons interesting for studies of…
Although 25%-50% of white dwarfs (WDs) display evidence for remnant planetary systems, their orbital architectures and overall sizes remain unknown. Vibrant close-in (~1 Solar radius) circumstellar activity is detected at WDs spanning many…
It has long been suspected that metal polluted white dwarfs (types DAZ, DBZ, and DZ) and white dwarfs with dusty disks possess planetary systems, but a specific physical mechanism by which planetesimals are perturbed close to a white dwarf…
The accretion of tidally disrupted planetary bodies is the current consensus model for the presence of photospheric metals commonly detected in white dwarfs. While most dynamical studies have considered a single star and associated…