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Source of atomic hydrogen in the atmosphere of HD 209458b

Liang, Mao-Chang and Parkinson, Christopher D. and Lee, Anthony Y. T. and Yung, Yuk L. and Seager, Sara (2003) Source of atomic hydrogen in the atmosphere of HD 209458b. Astrophysical Journal Letters, 596 (2). L247-L250. ISSN 2041-8205. doi:10.1086/379314.

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Atomic hydrogen loss at the top of HD 209458b's atmosphere has been recently suggested (Vidal-Madjar et al.). We have developed a one-dimensional model to study the chemistry in the upper atmosphere of this extrasolar "hot Jupiter." The three most abundant elements (other than He) as well as four parent molecules are included in this model, viz., H, C, O, H_2, CO, H_2O, and CH_4. The higher temperatures (~1000 K) and higher stellar irradiance (~6 × 10^5 W m^-2) strongly enhance and modify the chemical reaction rates in this atmosphere. The main result is that the production of atomic hydrogen in the atmosphere is mainly driven by H_2O photolysis, and the reaction of OH with H_2, and is insensitive to the exact abundances of CO, H_2O, and CH_4. For comparison, the bulk H concentration for "hot Jupiters" is 3 orders of magnitude higher than that of Jupiter.

Item Type:Article
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URLURL TypeDescription Paper
Liang, Mao-Chang0000-0002-5294-9344
Parkinson, Christopher D.0000-0002-5722-2224
Yung, Yuk L.0000-0002-4263-2562
Seager, Sara0000-0002-6892-6948
Additional Information:© 2003 The American Astronomical Society. Received 2003 June 27; accepted 2003 August 28; published 2003 September 18. We thank M. Gerstell, J. C. McConnell, R. L. Shia, and the referee D. Homeier for helpful comments. This work was supported by NASA grant NAG5-6263 and the Astrobiology program at JPL.
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NASA Astrobiology InstituteUNSPECIFIED
Issue or Number:2
Record Number:CaltechAUTHORS:20140826-160824682
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Official Citation:Source of Atomic Hydrogen in the Atmosphere of HD 209458b Mao-Chang Liang et al. 2003 ApJ 596 L247
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:48951
Deposited On:29 Aug 2014 22:01
Last Modified:10 Nov 2021 18:38

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