Results 41 to 50 of about 33,632 (191)
Scaling K2. VII. Evidence For a High Occurrence Rate of Hot Sub-Neptunes at Intermediate Ages
The Astronomical Journal, 2023 The NASA K2 mission obtained high-precision time-series photometry for four young clusters, including the near-twin 600–800 Myr old Praesepe and Hyades clusters. Hot sub-Neptunes are highly prone to mass-loss mechanisms, given their proximity to the host
Jessie L. Christiansen +8 more
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The Astronomical Journal, 2023 Irradiated Jovian atmospheres are complex and dynamic and can undergo temporal variations due to the close proximity of their parent stars. Of the Jovian planets that have been cataloged to date, KELT-9b is the hottest gas giant known, with an ...
Nataliea Lowson +12 more
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The GAPS Programme at TNG. LXI. Atmospheric parameters and elemental abundances of TESS young exoplanet host stars [PDF]
Astronomy & AstrophysicsThe study of exoplanets at different evolutionary stages can shed light on their formation, migration, and evolution. The determination of exoplanet properties depends on the properties of their host stars.
S. Filomeno +28 more
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Deuterium Escape on Photoevaporating Sub-Neptunes
The Astrophysical Journal Letters, 2023 We investigate the evolution of the deuterium-to-hydrogen (D/H) mass ratio driven by EUV photoevaporation of hydrogen-rich atmospheres of close-in sub-Neptunes around solar-type stars.
Pin-Gao Gu, Howard Chen
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Unveiling the atmospheric evolution of exoplanets
, 2021 A thorough characterisation of an exoplanetary system includes also studying the evolution of planetary atmospheres. To this end, we developed a custom tool to estimate the atmospheric content of exoplanets at the dispersal of the protoplanetary disk accounting for the present day system observables. In detail, our tool relies on planetary evolutionary
openaire +1 more source
The Astronomical Journal, 2023 Extremely low-density exoplanets are tantalizing targets for atmospheric characterization because of their promisingly large signals in transmission spectroscopy.
Aaron Bello-Arufe +8 more
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Nonthermal Atmospheric Escape on the Kepler-11 “Super-Earths” Driven by Stellar Wind Sputtering
The Astrophysical Journal, 2023 Jeans escape or hydrodynamic escape is believed to dominate atmospheric loss for hot Jupiters. However, nonthermal mechanisms likely contribute substantially on hydrogen-rich “super-Earths” with relatively cold and extended atmospheres.
Hao Gu +4 more
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Outflowing Helium from a Mature Mini-Neptune
The Astrophysical Journal Letters, 2023 We announce the detection of escaping helium from TOI 2134b, a mini-Neptune a few gigayears old. The average in-transit absorption spectrum shows a peak of 0.37% ± 0.05% and an equivalent width of W _avg = 3.3 ± 0.3 mÅ.
Michael Zhang +4 more
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Towards a Theory for the Atmospheres, Structure, and Evolution of Giant Exoplanets [PDF]
Proceedings of the International Astronomical Union, 2011 AbstractIn this short review, I summarize some of the salient features of the emerging theory of exoplanets in general, and of giant exoplanets in particular. A focus is on the characterization of transiting planets at primary and secondary eclipse, but various other related topics are covered, if only briefly.
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Fleeting but Not Forgotten: The Imprint of Escaping Hydrogen Atmospheres on Super-Earth Interiors
The Astrophysical JournalSmall, close-in exoplanets are divided into two subpopulations: super-Earths and sub-Neptunes. Most super-Earths are thought to have lost their primordially accreted hydrogen-dominated atmospheres via thermally driven winds.
James G. Rogers +2 more
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