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Debris disc stirring by secular perturbations from giant planets
Detectable debris discs are thought to require dynamical excitation (`stirring'), so that planetesimal collisions release large quantities of dust. We investigate the effects of the secularExpand
Foretellings of Ragnarök: World-engulfing Asymptotic Giants and the Inheritance of White Dwarfs
The search for planets around white dwarf stars, and evidence for dynamical instability around them in the form of atmospheric pollution and circumstellar disks, raises questions about the nature ofExpand
Dependence of a planet's chaotic zone on particle eccentricity: the shape of debris disc inner edges
The orbit of a planet is surrounded by a chaotic zone wherein nearby particles' orbits are chaotic and unstable. It was shown by Wisdom that the chaos is driven by the overlapping of mean motionExpand
WTS-2 b: a hot Jupiter orbiting near its tidal destruction radius around a K dwarf
We report the discovery of WTS-2 b, an unusually close-in 1.02-d hot Jupiter (M-P = 1.12M(J), R-P = 1.30R(J)) orbiting a K2V star, which has a possible gravitationally bound M-dwarf companion at 0.6Expand
Hot Jupiters and Cool Stars
Close-in planets are in jeopardy, as their host stars evolve off the main sequence (MS) to the subgiant and red giant phases. In this paper, we explore the influences of the stellar mass (in theExpand
A general model of resonance capture in planetary systems: first- and second-order resonances
Mean motion resonances are a common feature of both our own Solar system and of extrasolar planetary systems. Bodies can be trapped in resonance when their orbital semimajor axes change, for instanceExpand
The great escape: how exoplanets and smaller bodies desert dying stars
Mounting discoveries of extrasolar planets orbiting post-main sequence stars motivate studies aimed at understanding the fate of these planets. In the traditional “adiabatic” approximation, aExpand
Herschel 's “cold debris disks”: background galaxies or quiescent rims of planetary systems?
Infrared excesses associated with debris disk host stars detected so far peak at wavelengths around ~100 μm or shorter. However, 6 out of 31 excess sources studied in the Herschel Open Time KeyExpand
A planetesimal orbiting within the debris disc around a white dwarf star
A stable 123.4-minute periodic variation in the strength and shape of the Ca ii emission line profiles originating from the debris disc around the white dwarf SDSS J122859.93+104032 is interpreted as the signature of a solid-body planetesimal held together by its internal strength. Expand
Unstable low-mass planetary systems as drivers of white dwarf pollution
At least 25 percent of white dwarfs show atmospheric pollution by metals, sometimes accompanied by detectable circumstellar dust/gas discs or (in the case of WD 1145+017) transiting disintegratingExpand