气候变化领域集成服务门户(CCPortal): MAVEN-IUVS Observations of the CO2 + UV Doublet and CO Cameron Bands in the Martian Thermosphere: Aeronomy; Seasonal; and Latitudinal Distribution

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DOI	10.1029/2019JA026596
	MAVEN-IUVS Observations of the CO2 + UV Doublet and CO Cameron Bands in the Martian Thermosphere: Aeronomy; Seasonal; and Latitudinal Distribution
	Gérard J.-C.; Gkouvelis L.; Ritter B.; Hubert B.; Jain S.K.; Schneider N.M.
发表日期	2019
ISSN	21699380
起始页码	5816
结束页码	5827
卷号	124 期号:7
英文摘要	We analyze two Martian years of dayglow measurements of the CO Cameron bands and the CO2 + ultraviolet doublet (UVD) at 298–299 nm with the Imaging UltraViolet Spectrograph on board the Mars Atmosphere and Volatile EvolutioN (MAVEN) orbiter. We show that the altitude and the brightness of the two emissions peaks are strongly correlated, although data were collected over a wide range of latitudes and seasons. Averaged limb profiles are presented and compared with numerical simulations based on updated calculations of the production of the CO (a3Π) and the CO2 + (B 2Σ) states. The model simulations use the solar flux directly measured on board MAVEN with the Extreme Ultraviolet Monitor and the neutral densities provided by the Mars Climate Database version 5.3, adapted to the conditions of the observations. We show that the altitude and the shape of the sample limb profiles are well reproduced using the Mars Climate Database neutral atmosphere. The simulated peak intensities of the CO2 + UVD and Cameron bands are in good agreement considering the uncertainties on the excitation cross sections and the calibration of the Imaging Ultraviolet Spectrograph (IUVS) and Extreme Ultraviolet Monitor instruments. No significant adjustment of the electron impact cross section on CO2 to produce the a3Π state is needed. Seasonal-latitudinal maps of the Cameron and UVD peak altitude observed during two Martian years show variations as large as 23 km. Model simulations of the amplitude of these changes are in fair agreement with the observations except during the southern summer dust period (Ls = 270–320°) when the calculated rise of the dayglow layer is underestimated. ©2019. American Geophysical Union. All Rights Reserved.
英文关键词	carbon dioxide; composition; dust storm; Mars atmosphere; MAVEN; ultraviolet dayglow
来源期刊	Journal of Geophysical Research: Space Physics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/176546
作者单位	LPAP, STAR Institute, Université de Liège, Liège, Belgium; LASP, University of Colorado Boulder, Boulder, CO, United States
推荐引用方式 GB/T 7714	Gérard J.-C.,Gkouvelis L.,Ritter B.,et al. MAVEN-IUVS Observations of the CO2 + UV Doublet and CO Cameron Bands in the Martian Thermosphere: Aeronomy; Seasonal; and Latitudinal Distribution[J],2019,124(7).
APA	Gérard J.-C.,Gkouvelis L.,Ritter B.,Hubert B.,Jain S.K.,&Schneider N.M..(2019).MAVEN-IUVS Observations of the CO2 + UV Doublet and CO Cameron Bands in the Martian Thermosphere: Aeronomy; Seasonal; and Latitudinal Distribution.Journal of Geophysical Research: Space Physics,124(7).
MLA	Gérard J.-C.,et al."MAVEN-IUVS Observations of the CO2 + UV Doublet and CO Cameron Bands in the Martian Thermosphere: Aeronomy; Seasonal; and Latitudinal Distribution".Journal of Geophysical Research: Space Physics 124.7(2019).