On the thermal electron balance in Titan's sunlit upper atmosphere
文献类型：期刊论文
| 作者 | Vigren, E.1; Galand, M.1; Yelle, R. V.2; Cui, J.3,4 ; Wahlund, J. -E.5; Agren, K.5; Lavvas, P. P.6; Mueller-Wodarg, I. C. F.1; Strobel, D. F.7; Vuitton, V.8
|
| 刊名 | ICARUS
 |
| 出版日期 | 2013-03-01 |
| 卷号 | 223期号:1页码:234-251 |
| 关键词 | Titan Ionospheres Atmospheres, Chemistry |
| 英文摘要 | The Cassini mission has investigated Titan's upper atmosphere in detail and found that, under solar irradiation, it has a well-developed ionosphere, which peaks between 1000 and 1200 km. In this paper we focus on the T40, T41, T42 and T48 Titan flybys by the Cassini spacecraft and use in situ measurements of N-2 and CH4 densities by the Ion Neutral Mass Spectrometer (INMS) as input into a solar energy deposition model to determine electron production rates. We combine these electron production rates with estimates of the effective recombination coefficient based on available laboratory data for Titan ions' dissociative recombination rates and electron temperatures derived from the Langmuir probe (LP) to predict electron number densities in Titan's upper atmosphere, assuming photochemical equilibrium and loss of electrons exclusively through dissociative recombination with molecular ions. We then compare these predicted electron number densities with those observed in Titan's upper atmosphere by the LP. The assumption of photochemical equilibrium is supported by a reasonable agreement between the altitudes where the electron densities are observed to peak and where the electron production rates are calculated to peak (roughly corresponding to the unit optical depth for Hell photons at 3038 nm). We find, however, that the predicted electron number densities are nearly a factor of two higher than those observed throughout the altitude range between 1050 and 1200 km (where we have made estimates of the effective recombination coefficient). There are different possible reasons for this discrepancy; one possibility is that there may be important loss processes of free electrons other than dissociative recombination in Titan's upper atmosphere. (C) 2012 Elsevier Inc. All rights reserved. |
| 收录类别 | SCI |
| 语种 | 英语 |
| WOS记录号 | WOS:000315977600018 |
| 源URL | [http://ir.bao.ac.cn/handle/114a11/6039]  |
| 专题 | 国家天文台_月球与深空探测研究部 |
| 作者单位 | 1.Univ London Imperial Coll Sci Technol & Med, Dept Phys, London SW7 2AZ, England 2.Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA 3.Nanjing Univ, Sch Astron & Space Sci, Nanjing 210008, Jiangsu, Peoples R China 4.Chinese Acad Sci, Natl Astron Observ, Beijing 100012, Peoples R China 5.Swedish Inst Space Phys, Uppsala, Sweden 6.Univ Reims, Grp Spectrometrie Mol & Atmospher, UMR 7331, F-51687 Reims, France 7.Johns Hopkins Univ, Dept Earth & Planetary Sci, Baltimore, MD 21218 USA 8.UJF Grenoble CNRS INSU, IPAG, F-38041 Grenoble, France |
| 推荐引用方式 GB/T 7714 | Vigren, E.,Galand, M.,Yelle, R. V.,et al. On the thermal electron balance in Titan's sunlit upper atmosphere[J]. ICARUS,2013,223(1):234-251. |
| APA | Vigren, E..,Galand, M..,Yelle, R. V..,Cui, J..,Wahlund, J. -E..,...&Bazin, A..(2013).On the thermal electron balance in Titan's sunlit upper atmosphere.ICARUS,223(1),234-251. |
| MLA | Vigren, E.,et al."On the thermal electron balance in Titan's sunlit upper atmosphere".ICARUS 223.1(2013):234-251. |
入库方式： OAI收割
来源：国家天文台
浏览0
下载0
收藏0
其他版本
除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。