| Full text | |
| Author(s): |
Roudier, Gael M.
[1]
;
Swain, Mark R.
[1]
;
Gudipati, Murthy S.
[1]
;
West, Robert A.
[1]
;
Estrela, Raissa
[1]
;
Zellem, Robert T.
[1]
Total Authors: 6
|
| Affiliation: | [1] CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 - USA
Total Affiliations: 1
|
| Document type: | Journal article |
| Source: | ASTRONOMICAL JOURNAL; v. 162, n. 2 AUG 2021. |
| Web of Science Citations: | 1 |
| Abstract | |
Literature on the theory of exoplanet atmospheric disequilibrium chemistry is rich, although its observational counterpart has yet to emerge beyond the hints provided by a few targets in dedicated studies. We report results from an uniform data reduction and analysis for a catalog of 62 Hubble Space Telescope exoplanet transit spectra where we assess the atmospheric model preference for disequilibrium chemistry (i.e., water vapor is not the dominant absorption spectral signature) over thermal equilibrium chemistry in a comparative planetology context. Where model preference assessment is possible, we find that disequilibrium occurs in about half of the atmospheres, indicating that disequilibrium processes play an important role in the composition of exoplanet atmospheres. While very hot atmospheres, over 1800 K, prefer equilibrium chemistry, we find a clustering of preference for disequilibrium in the 1200-1800 K temperature range. We suggest that UV-augmented thermochemistry may play a significant role for those atmospheres. (AU) | |
| FAPESP's process: | 18/09984-7 - Unveiling haze formation and energy balance in the exoplanets atmospheres with the Hubble Space Telescope |
| Grantee: | Raissa de Lourdes Freitas Estrela |
| Support Opportunities: | Scholarships abroad - Research Internship - Doctorate |