相关论文: Transiting Disintegrating Planetary Debris around …
White dwarfs which exhibit transit signatures of planetary debris and accreted planetary material provide exceptional opportunities to probe the material composition and dynamical structure of planetary systems. Although previous…
Many white dwarf stars show signs of having accreted smaller bodies, implying that they may host planetary systems. A small number of these systems contain gaseous debris discs, visible through emission lines. We report a stable 123.4min…
About 25\% -50\% of white dwarfs (WDs) are found to be polluted by heavy elements. It has been argued that the pollution could be caused by the tidal disruption of an approaching planet around the WD, during which a large number of clumps…
White dwarfs are routinely observed to have polluted atmospheres, and sometimes significant infrared excesses, that indicate ongoing accretion of circumstellar dust and rocky debris. Typically this debris is assumed to be in the form of a…
Dynamically active planetary systems orbit a significant fraction of white dwarf stars. These stars often exhibit surface metals accreted from debris disks, which are detected through infrared excess or transiting structures. However, the…
We performed a chemical analysis of the asteroid-bearing white dwarf WD 1145+017 using optical and ultraviolet spectroscopic data from 25 epochs between 2015 and 2023. We present an updated gas disk model with improved opacity calculations…
Numerous white dwarf stars are known to be orbited by disks of gas and dust. To date, broad, about 300 km s-1 wide, gaseous circumstellar absorption features have only been reported for the already iconic WD 1145+017, where one is…
We have observed several relatively deep transits of the white dwarf WD 1145+017 with the GTC over the wavelength range 480 nm to 920 nm. The observations covered approximately one hour on 2016 Jan 18 and two hours on 2016 Jan 20. There was…
This is a short and rather narrative summary of our ongoing efforts in identifying white dwarfs with gaseous debris disks, and developing an understanding of the structure and origin of these disks.
Between 25-50 % of white dwarfs (WD) present atmospheric pollution by metals, mainly by rocky material, which has been detected as gas/dust discs, or in the form of photometric transits in some WDs. Planets might be responsible for…
There is a wealth of evidence to suggest that planetary systems can survive beyond the main sequence. Most commonly, white dwarfs are found to be accreting material from tidally disrupted asteroids, whose bulk compositions are reflected by…
Do white dwarfs host asteroid systems? Although several lines of argument suggest that white dwarfs may be orbited by large populations of asteroids, transits would provide the most direct evidence. We demonstrate that the Kepler mission…
With the recent discovery of transiting planetary material around WD 1145+017, a critical target has been identified that links the evolution of planetary systems with debris disks and their accretion onto the star. We present a series of…
The surfaces of many white dwarfs are polluted by metals, implying a recent accretion event. The tidal disruption of planetesimals is a viable source of white dwarf pollution and offers a unique window into the composition of exoplanet…
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…
Post-main-sequence planetary science has been galvanised by the striking variability, depth and shape of the photometric transit curves due to objects orbiting white dwarf WD 1145+017, a star which also hosts a dusty debris disc and…
The photospheres of some white dwarfs are "polluted" by accretion of material from their surrounding planetary debris. White dwarfs with dust disks are often heavily polluted and high-resolution spectroscopic observations of these systems…
An ice giant planet was recently reported orbiting white dwarf WD J0914+1914 at an approximate distance of 0.07 au. The striking non-detection of rocky pollutants in this white dwarf's photosphere contrasts with the observations of nearly…
We present an eccentric precessing gas disk model designed to study the variable circumstellar absorption features detected for WD 1145+017, a metal polluted white dwarf with an actively disintegrating asteroid around it. This model,…
Many potential mechanisms for delivering planetary debris to within a few Roche radii of white dwarfs rely on gravitational scattering events that feature perturbers which are giant planets or terrestrial planets. However, the population of…