Photochemical escape of atomic C and N on Mars: clues from a multi-instrument MAVEN dataset

doi:10.1051/0004-6361/201833749

CORC > 国家天文台 > 中国科学院国家天文台

	Photochemical escape of atomic C and N on Mars: clues from a multi-instrument MAVEN dataset
	Cui, J.2,3,4; Wu, X. -S.3; Gu, H.5; Jiang, F. -Y.3; Wei, Y.1
刊名	ASTRONOMY & ASTROPHYSICS
	2018-12-21
卷号	621 页码:8
关键词	planets and satellites: individual: Mars planets and satellites: atmospheres
ISSN号	1432-0746
DOI	10.1051/0004-6361/201833749
英文摘要	Context. Photochemical escape of hot atoms is crucial to the long-term evolution of the Martian climate. For atomic C and N, photochemical escape is primarily driven by photodissociation (PD) of CO and N-2. Aims. Combining the Mars Atmosphere and Volatile Evolution (MAVEN) measurements of atmospheric neutral densities and solar EUV/X-ray irradiance, we perform a state-of-the-art analysis of atomic C and N escape on Mars. Methods. For each MAVEN orbit, we calculated the hot C and N production rates in the dayside Martian upper atmosphere via PD, from which the escape rates are estimated using a simplified technique to parameterize the respective escape probabilities taking into account multiple collisions with ambient neutrals. Results. The mean C and N escape rates are 1 x 10(24) s(-1) and 9 x 10(24) s(-1), appropriate for low to moderate solar activity conditions, and thermospheric PD makes a larger contribution to the total N escape than to the total C escape. The above differences highlight the importance of nascent energy, with more energetic nascent escaping atoms able to survive collisions with ambient neutrals more easily, thus extending down to deeper regions of the atmosphere. Solar cycle variation in C and N escape is revealed by our analysis, whereas solar zenith angle variation is absent for both species. These results could be explained by the fact that the production of nascent escaping atoms responds to varying solar illumination angle at low altitudes where the escape probability is negligible, but responds to varying level of solar EUV/X-ray irradiance at high altitudes where the atmosphere is essentially collisionless.
资助项目	National Science Foundation of China (NSFC)[41525015] ; National Science Foundation of China (NSFC)[41774186] ; National Science Foundation of China (NSFC)[41525016] ; Science and Technology Development Fund of Macau SAR (FDCT)[039/2013/A2] ; Science and Technology Development Fund of Macau SAR (FDCT)[082/2015/A3]
WOS关键词	HOT OXYGEN ; DISSOCIATIVE RECOMBINATION ; UPPER-ATMOSPHERE ; CROSS-SECTIONS ; NITROGEN-ATOMS ; IONOSPHERE ; CARBON ; DISTRIBUTIONS ; EXCITATION ; EVOLUTION
WOS研究方向	Astronomy & Astrophysics
语种	英语
出版者	EDP SCIENCES S A
WOS记录号	WOS:000454402800001
资助机构	National Science Foundation of China (NSFC) ; National Science Foundation of China (NSFC) ; Science and Technology Development Fund of Macau SAR (FDCT) ; Science and Technology Development Fund of Macau SAR (FDCT) ; National Science Foundation of China (NSFC) ; National Science Foundation of China (NSFC) ; Science and Technology Development Fund of Macau SAR (FDCT) ; Science and Technology Development Fund of Macau SAR (FDCT) ; National Science Foundation of China (NSFC) ; National Science Foundation of China (NSFC) ; Science and Technology Development Fund of Macau SAR (FDCT) ; Science and Technology Development Fund of Macau SAR (FDCT) ; National Science Foundation of China (NSFC) ; National Science Foundation of China (NSFC) ; Science and Technology Development Fund of Macau SAR (FDCT) ; Science and Technology Development Fund of Macau SAR (FDCT)
内容类型	期刊论文
源URL	[http://ir.bao.ac.cn/handle/114a11/24249]
专题	中国科学院国家天文台
通讯作者	Cui, J.
作者单位	1.Chinese Acad Sci, Inst Geol & Geophys, Key Lab Earth & Planetary Phys, Beijing, Peoples R China 2.Sun Yat Sen Univ, Sch Atmospher Sci, Zhuhai, Peoples R China 3.Chinese Acad Sci, Key Lab Lunar & Deep Space Explorat, Natl Astron Observ, Beijing, Peoples R China 4.Chinese Acad Sci, Ctr Excellence Comparat Planetol, Hefei, Anhui, Peoples R China 5.Macau Univ Sci & Technol, Space Sci Inst, Macau, Peoples R China
推荐引用方式 GB/T 7714	Cui, J.,Wu, X. -S.,Gu, H.,et al. Photochemical escape of atomic C and N on Mars: clues from a multi-instrument MAVEN dataset[J]. ASTRONOMY & ASTROPHYSICS,2018,621:8.
APA	Cui, J.,Wu, X. -S.,Gu, H.,Jiang, F. -Y.,&Wei, Y..(2018).Photochemical escape of atomic C and N on Mars: clues from a multi-instrument MAVEN dataset.ASTRONOMY & ASTROPHYSICS,621,8.
MLA	Cui, J.,et al."Photochemical escape of atomic C and N on Mars: clues from a multi-instrument MAVEN dataset".ASTRONOMY & ASTROPHYSICS 621(2018):8.