Multiwavelength Observations of Disintegrating Transiting Planets &
Planetesimals
Bryce Croll
Institute for Astrophysical Research, Boston University
Recently there have been a number of low-mass planets and planetesimals
announced (or soon to be announced) transiting low-mass stars and even a
white dwarf - intriguingly, these planets are believed to be disintegrating
with long cometary tails trailing behind them. The evidence that these
bodies are disintegrating are: (i) that they usually display longer transit
egresses than ingresses, likely indicative of a trailing cometary tail, and
(ii) they they display variable transit depths, likely indicative of light
scattering from a variable amount of material in the cometary tail that has
disintegrated from the planet. I'll present multiwavelength photometry that
allows us to place limits on the particle sizes in the cometary tails
trailing these planets, and therefore helps to determine the mechanism
causing these planets to disintegrate. I'll finish with an in-depth
discussion of the up to six or more disintegrating planetesimals in short
periods (<5 hour) orbits that are shortly to be announced orbiting a single
white dwarf - I will explain how the multiwavelength photometry that we've
obtained helps to answer how many planetesimals are actually orbiting this
white dwarf, whether the orbits of these objects are stable, and what the
most likely mechanism is (tidal disruption, collisions, a Parker-wind,
etc.) that has led to both these planetesimals' cometary tails and the
arrival of these bodies in such short period orbits.
Date: | Jeudi, le 15 octobre 2015 |
Heure: | 11:30 |
Lieu: | Université de Montréal |
| Pavillon Roger-Gaudry, local D-460 |
Contact: | Patrick Dufour |
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