Temporal Evolution of the High-energy Irradiation and Water Content of TRAPPIST-1 Exoplanets

@article{VBourrier2017TemporalEO,
  title={Temporal Evolution of the High-energy Irradiation and Water Content of TRAPPIST-1 Exoplanets},
  author={V.Bourrier and Julien de Wit and E.Bolmont and V.Stamenkovic and P.J.Wheatley and Adam J. Burgasser and L.Delrez and B.-O.Demory and D.Ehrenreich and M.Gillon and E.Jehin and J.Leconte and S.M.Lederer and N.Lewis and A.H.M.J.Triaud and Val{\'e}rie Van Grootel},
  journal={The Astronomical Journal},
  year={2017},
  volume={154},
  pages={121}
}
The ultracool dwarf star TRAPPIST-1 hosts seven Earth-size transiting planets, some of which could harbor liquid water on their surfaces. Ultraviolet observations are essential to measuring their high-energy irradiation and searching for photodissociated water escaping from their putative atmospheres. Our new observations of the TRAPPIST-1 Lyα line during the transit of TRAPPIST-1c show an evolution of the star emission over three months, preventing us from assessing the presence of an extended… 
Surface and Oceanic Habitability of Trappist-1 Planets under the Impact of Flares.
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It is found that for non-oxygenic planets, UV-resistant life-forms would survive on the surface of planets f and g, and more fragile organisms (i.e., Escherichia coli) could be protected from the hazardous UV effects at ocean depths greater than 8 m.
A Coupled Analysis of Atmospheric Mass Loss and Tidal Evolution in XUV Irradiated Exoplanets: The TRAPPIST-1 Case Study
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Water delivery to the TRAPPIST-1 planets
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TLDR
It is shown that (i) Hubble Space Telescope transit observations, (ii) bulk density measurements comparison with H2-rich planets mass-radius relationships, (iii) atmospheric escape modelling, and (iv) gas accretion modelling altogether offer solid evidence against the presence of hydrogen-dominated—cloud-free and cloudy—atmospheres around TRAPPIST-1 planets.
Atmospheric reconnaissance of the habitable-zone Earth-sized planets orbiting TRAPPIST-1
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Interior Structures and Tidal Heating in the TRAPPIST-1 Planets
With seven planets, the TRAPPIST-1 system has the largest number of exoplanets discovered in a single system so far. The system is of astrobiological interest, because three of its planets orbit in
Predicting the Extreme Ultraviolet Radiation Environment of Exoplanets around Low-mass Stars: The TRAPPIST-1 System
The high energy radiation environment around M dwarf stars strongly impacts the characteristics of close-in exoplanet atmospheres, but these wavelengths are difficult to observe due to geocoronal and
The nature of the TRAPPIST-1 exoplanets.
Context. The TRAPPIST-1 system hosts seven Earth-sized, temperate exoplanets orbiting an ultra-cool dwarf star. As such, it represents a remarkable setting to study the formation and evolution of
The high-energy environment and atmospheric escape of the mini-Neptune K2-18 b
K2-18 b is a transiting mini-Neptune that orbits a nearby (38 pc), cool M3 dwarf and is located inside its region of temperate irradiation. We report on the search for hydrogen escape from the
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TLDR
Observations of the combined transmission spectrum of the two inner planets during their simultaneous transits on 4 May 2016 rule out cloud-free hydrogen-dominated atmospheres for each planet at ≥10σ levels; TRAPPIST-1 b and c are therefore unlikely to have an extended gas envelope as they occupy a region of parameter space in which high-altitude cloud/haze formation is not expected to be significant for hydrogen- dominated atmospheres.
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TLDR
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TLDR
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The newly detected TRAPPIST-1 system, with seven low-mass, roughly Earth-sized planets transiting a nearby ultra-cool dwarf, is one of the most important exoplanet discoveries to date. The short
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