THE INFLUENCE OF THE EXTREME ULTRAVIOLET SPECTRAL ENERGY DISTRIBUTION ON THE STRUCTURE AND COMPOSITION OF THE UPPER ATMOSPHERE OF EXOPLANETS

	THE INFLUENCE OF THE EXTREME ULTRAVIOLET SPECTRAL ENERGY DISTRIBUTION ON THE STRUCTURE AND COMPOSITION OF THE UPPER ATMOSPHERE OF EXOPLANETS
	Guo JH(郭建恒)1,2 ; Ben-Jaffel, Lotfi 3,4
刊名	ASTROPHYSICAL JOURNAL
	2016-02-20
卷号	818 期号:2
关键词	planets and satellites: atmospheres planets and satellites: individual (HD 209458b, GJ 436b, HD 189733b, Kepler-11b) ultraviolet: stars
ISSN号	0004-637X
通讯作者	Guo, JH
产权排序	第一完成单位
英文摘要	By varying the profiles of stellar extreme ultraviolet (EUV) spectral energy distributions (SEDs), we tested the influences of stellar EUV SEDs on the physical and chemical properties of an escaping atmosphere. We apply our model to study four exoplanets: HD 189733b, HD 209458b, GJ 436b, and Kepler-11b. We find that the total mass loss rates of an exoplanet, which are determined mainly by the integrated fluxes, are moderately affected by the profiles of the EUV SED, but the composition and species distributions in the atmosphere can be dramatically modified by the different profiles of the EUV SED. For exoplanets with a high hydrodynamic escape parameter (.), the amount of atomic hydrogen produced by photoionization at different altitudes can vary by one to two orders of magnitude with the variation of stellar EUV SEDs. The effect of photoionization of H is prominent when the EUV SED is dominated by the low-energy spectral region (400-900 angstrom), which pushes the transition of H/H+ to low altitudes. In contrast, the transition of H/H+ moves to higher altitudes when most photons are concentrated in the high-energy spectral region (50-400 angstrom). For exoplanets with a low., the lower temperatures of the atmosphere make many chemical reactions so important that photoionization alone can no longer determine the composition of the escaping atmosphere. For HD 189733b, it is possible to explain the time variability of Ly alpha between 2010 and 2011 by a change in the EUV SED of the host K-type star, yet invoking only thermal H I in the atmosphere.
学科主题	Astronomy & Astrophysics
WOS标题词	Science & Technology ; Physical Sciences
类目[WOS]	Astronomy & Astrophysics
研究领域[WOS]	Astronomy & Astrophysics
关键词[WOS]	ESCAPING PARTICLE FLUXES ; M5 V STARS ; HD 209458B ; MASS-LOSS ; HOT JUPITERS ; DISSOCIATIVE-RECOMBINATION ; PLANETARY-ATMOSPHERES ; EXTRASOLAR PLANETS ; ANISOTROPIC WINDS ; GIANT PLANETS
收录类别	SCI
原文出处	http://iopscience.iop.org/article/10.3847/0004-637X/818/2/107/meta
语种	英语
WOS记录号	WOS:000372302800006
内容类型	期刊论文
源URL	[http://ir.ynao.ac.cn/handle/114a53/9359]
专题	云南天文台_恒星物理研究组云南天文台_中国科学院天体结构与演化重点实验室
作者单位	1.Yunnan Observatories, Chinese Academy of Sciences, P.O. Box 110, Kunming 650011, China 2.Key Laboratory for the Structure and Evolution of Celestial Objects, CAS, Kunming 650011, China 3.Sorbonne Universités, UPMC Univ. Paris 6 et CNRS, UMR 7095, Institut Astrophysique de Paris, F-75014 Paris, France 4.Visiting Research Scientist, University of Arizona, Lunar & Planetary Laboratory, Tucson, AZ, USA
推荐引用方式 GB/T 7714	Guo JH,Ben-Jaffel, Lotfi. THE INFLUENCE OF THE EXTREME ULTRAVIOLET SPECTRAL ENERGY DISTRIBUTION ON THE STRUCTURE AND COMPOSITION OF THE UPPER ATMOSPHERE OF EXOPLANETS[J]. ASTROPHYSICAL JOURNAL,2016,818(2).
APA	Guo JH,&Ben-Jaffel, Lotfi.(2016).THE INFLUENCE OF THE EXTREME ULTRAVIOLET SPECTRAL ENERGY DISTRIBUTION ON THE STRUCTURE AND COMPOSITION OF THE UPPER ATMOSPHERE OF EXOPLANETS.ASTROPHYSICAL JOURNAL,818(2).
MLA	Guo JH,et al."THE INFLUENCE OF THE EXTREME ULTRAVIOLET SPECTRAL ENERGY DISTRIBUTION ON THE STRUCTURE AND COMPOSITION OF THE UPPER ATMOSPHERE OF EXOPLANETS".ASTROPHYSICAL JOURNAL 818.2(2016).