相关论文: Pollution of single white dwarfs by accretion of m…
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…
This paper investigates the frequency of transiting planetary systems around metal-polluted white dwarfs using high-cadence photometry from ULTRACAM and ULTRASPEC on the ground, and space-based observations with TESS. Within a sample of 313…
A persistent question in exoplanet demographics is whether exoplanetary systems form from similar compositional building blocks to our own. Polluted white dwarf stars offer a unique way to address this question as they provide measurements…
Context. About 25% -- 50% of white dwarfs are found to be contaminated by heavy elements, which are believed to originate from external sources such as planetary materials. Elemental abundances suggest that most of the pollutants are rocky…
We present the Planetary Enriched White Dwarf Database (PEWDD), a collection of published photospheric abundances of white dwarfs accreting planetary debris alongside additional information relevant to metal-enrichment and the presence of…
Hydrogen atmosphere white dwarfs with metal lines, so-called DAZs, require external accretion of material to explain the presence of weak metal line absorption in their photospheres. The source of this material is currently unknown, but…
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…
Dozens of white dwarfs with anomalous metal polluted atmospheres (DZ WDs) are known to host dust and gas discs. The line profiles of the Ca II triplet emitted by the gas discs show significant asymmetry. Several minor planets have been…
With XMM-Newton and the Spitzer Space Telescope, we obtain upper bounds to the X-ray fluxes from G29-38 and GD 362, and the 70 micron flux from G29-38. These data provide indirect evidence that G29-38 is accreting from a tidally-disrupted…
The analysis of noble gases in primitive meteorites has shown the existence of anomalous isotopic abundances when compared with the average Solar System values. In particular it has been found that some graphite grains contain a unexpected…
The evolution of planetary systems around white dwarfs is crucial to understanding the presence of planetary material in the atmospheres of white dwarfs. These systems uniquely probe exoplanetary compositions. Periodic signals in the…
White dwarf planetary science is a rapidly growing field of research featuring a diverse set of observations and theoretical explorations. Giant planets, minor planets, and debris discs have all been detected orbiting white dwarfs. The…
Observations of debris disks, the products of the collisional evolution of rocky planetesimals, can be used to trace planetary activity across a wide range of stellar types. The most common end points of stellar evolution are no exception…
Understanding the fate of planetary systems through white dwarfs which accrete debris crucially relies on tracing the orbital and physical properties of exo-asteroids during the giant branch phase of stellar evolution. Giant branch…
We present new results on PHL 5038AB, a widely separated binary system composed of a white dwarf and a brown dwarf, refining the white and brown dwarf parameters and determining the binary separation to be $66^{+12}_{-24}$~AU. New spectra…
We systematically investigate the mergers of neutron star-white dwarf binaries from beginning to end, with focus on the properties of the inflows and outflows in accretion disks and their electromagnetic emissions. Using population…
In the Solar System short-lived radioisotopes, such as 26Al, played a crucial role during the formation planetary bodies by providing a significant additional source of heat. Notably, this led to early and large-scale melting and iron core…
Nearly all known white dwarf planetary systems contain detectable rocky debris in the stellar photosphere. A glaring exception is the young and still evolving white dwarf WD J0914+1914, which instead harbours a giant planet and a disc of…
There is increasing evidence for the presence and variability of circumstellar dust and gas around white dwarfs that are polluted with exoplanetary material, although the origin of this dust and gas remains debated. This paper presents the…
The accretion of comets onto DA white dwarfs can produce observable metal absorption lines. We show here that comet systems around the progenitor main sequence star are vulnerable to being lost during asymptotic giant branch mass loss, if…