Chemical kinetics plays an important role in controlling the atmospheric composition of all planetary atmospheres, including those of extrasolar planets. For the hottest exoplanets, the composition can closely follow thermochemical-equilibrium predictions, at least in the visible and infrared photosphere at dayside (eclipse) conditions.
However, for atmospheric temperatures < ~2000 K, and in the uppermost atmosphere at any temperature, chemical kinetics matters. The two key mechanisms by which kinetic processes drive an exoplanet atmosphere out of equilibrium are photochemistry and transport-induced quenching. We review these disequilibrium processes in detail, discuss observational consequences, and examine some of the current evidence for kinetic processes on extrasolar planets.
Julianne I. Moses (Submitted on 20 Jul 2013)
Comments: submitted to Phil. Trans. Roy. Soc. A in February 2013
Subjects: Earth and Planetary Astrophysics (astro-ph.EP)
Cite as: arXiv:1307.5450 [astro-ph.EP]
(or arXiv:1307.5450v1 [astro-ph.EP] for this version) Submission history From: Julianne Moses [view email] [v1] Sat, 20 Jul 2013 18:48:31 GMT (272kb)
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