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arXiv · 0808.3987

Atmospheric composition and structure of HD209458b

J. -M. Désert·A. Vidal-Madjar·A. Lecavelier des Etangs·D. Sing·D. Ehrenreich·G. Hébrard·R. Ferlet
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Abstract

Transiting planets like HD209458b offer a unique opportunity to scrutinize their atmospheric composition and structure. Transit spectroscopy probes the transition region between the day and night sides, called limb. We present a re-analysis of existing archived HST/STIS transmission spectra of HD209458b's atmosphere. From these observations we: Identify H2 Rayleigh scattering, derive the absolute Sodium abundance and quantify its depletion in the upper atmosphere, extract a stratospheric T-P profile with a temperature inversion and explain broad band absorptions with the presence of TiO and VO molecules in the atmosphere of this planet.

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J. -M. Désert, A. Vidal-Madjar, A. Lecavelier des Etangs, D. Sing, D. Ehrenreich, G. Hébrard, R. Ferlet. 2008-08-28. Atmospheric composition and structure of HD209458b. https://doi.org/10.1017/s1743921308027117

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