博碩士論文 104623006 詳細資訊




以作者查詢圖書館館藏 以作者查詢臺灣博碩士 以作者查詢全國書目 勘誤回報 、線上人數:6 、訪客IP:54.221.145.174
姓名 楊雋敏(Chun-Min Yang)  查詢紙本館藏   畢業系所 太空科學研究所
論文名稱 土衛六泰坦大氣的甲烷在土星系統的分佈
(The Density Distribution of Methane Escaping from Titan′s Atmosphere in the Saturnian System)
相關論文
★ 日冕拋射物質現象在太陽第23週期之統計研究★ 土星環粒子隨時間變化之表面溫度模擬
★ RHESSI觀測M型太陽閃焰的動態結構分析★ 太陽活動寧靜期日冕層影像與解析磁場模型之影像套疊與應用
★ 土衛八Iapetus的外球層模型★ 月球表面反射太陽風質子之粒子模擬
★ 土衛六-泰坦的大氣層密度和溫度的三維分佈★ 日冕物質拋射速度與緯度和太陽活動週期的關係
★ 隨季節變化之灶神星冰極模擬★ 藉由卡西尼太空船MIMI/LEMMS觀測資料分析土星高能電漿入射來源之統計
★ 土星環鄰近地區之帶電塵埃粒子動力學★ 直接模擬蒙地卡羅法於彗星之噴氣和塵埃噴流之應用
★ 克普勒任務觀測G型星超級閃焰的資料分析★ The Measurements of the Gas Density Distributions and Composition in the Water Plumes of Enceladus by the INMS Instrument on Cassini
★ 木星環系統帶電粒子動力學分析與 全球碰撞分布地圖--為JUNO任務預測★ 冥王星與其它矮行星的大氣季節性演化
檔案 [Endnote RIS 格式]    [Bibtex 格式]    [相關文章]   [文章引用]   [完整記錄]   [館藏目錄]   [檢視]  [下載]
  1. 本電子論文使用權限為同意立即開放。
  2. 已達開放權限電子全文僅授權使用者為學術研究之目的,進行個人非營利性質之檢索、閱讀、列印。
  3. 請遵守中華民國著作權法之相關規定,切勿任意重製、散佈、改作、轉貼、播送,以免觸法。

摘要(中) 行星大氣的外球層在熱平衡狀態,氣體分子遵循馬克斯威爾速度分佈,其中動能超過重力位能者可能脫離該天體,即所謂的大氣逃逸。已知土星環系統主要由中性氣體雲組成,這些氣體一部分由來自土星的衛星,例如土衛六泰坦提供了氮氣、甲烷與氫氣。2004年10月26日至2014年12月10日止,卡西尼(Cassini)探測器共計30次飛掠泰坦,透過離子與中性物質質譜儀(INMS)與惠更斯大氣結構分析儀(HASI)的紀錄,泰坦大氣結構與成分便逐一揭曉(Waite et al., 2005; Fulchignoni et al., 2005)。

Yelle et al. (2008)、Strobel (2009)與Cui et al. (2012)以流體模型擬合INMS觀測的泰坦大氣甲烷密度分佈,並預測甲烷(CH_4)逃逸率相當於?10?^27 s^(-1),這個遠大於瓊斯逃逸率的數值飽受爭議。Tucker & Johnson (2009)與Schaufelberger et al. (2012)以蒙地卡羅直接模擬法 (DSMC)計算泰坦外球層區域氣體分子之間的碰撞與位移,顯示即使採用瓊斯逃逸率也能夠重建同樣的觀測資料。

  根據甲烷從泰坦大氣逃逸的可能,我們選擇瓊斯逃逸率6.3×?10?^17 s^(-1)作甲烷的產率,在土星-泰坦系統內以限制性三體運動模擬大氣逃逸並考慮甲烷在系統內主要受光化學分解作用而產生CH_3、CH_2、CH與C,進一步計算這些粒子的密度分佈。此外,我們參考雙重馬克斯能量分佈,由(2-5)%超高溫甲烷增加高速粒子的比例(Jiang et al., 2017),分別揀選兩個特別高的甲烷產率1.2×?10?^25 CH_4 s^(-1)與2.2×?10?^27 CH_4 s^(-1)並建立兩組密度分佈與原本的瓊斯逃逸模型互相比較。

  所有的模型均顯示甲烷家族的密度分佈集中於泰坦的軌道與土星A環之間,高產率與被拓寬的高速分佈則分別使氣體雲的密度更大且分佈範圍更寬廣,假設甲烷的逸散率計算正確,泰坦就是土星環系統碳元素的主要來源之一;但,來自卡西尼電漿光譜儀(CAPS)的觀測數據,並沒有足夠數量的含碳離子證實甲烷氣環的存在(Johnson, 2009; Arridge et al., 2011),這些觀測反映流體擴散模型可能高估甲烷的逃逸率,或土星環內存在其它未知的機制抑制了碳離子的產量。
摘要(英) Atoms and molecules in an atmosphere in thermodynamic equilibrium have velocities which follow the Maxwell-Boltzmann distribution law. Some of these particles may escape to space if its energy is kinetic greater than its gravitational binding energy. The ring system of Saturn is dominated by neutral gas clouds originating from the icy satellites. One significant source of them, Titan, continuously provides?? N?_2,CH?_4,H_2. Thirty Cassini flybys with Titan, from 26 October 2004 to 10 December 2014, reveal the structure of its upper atmosphere by the Ion and Neutral Mass Spectrometer (INMS) and Huygens Atmospheric Structure Instrument (HASI) measurements (Waite et al., 2005; Fulchignoni et al., 2005).

With the CH_4 density profile based on the observations fitted by fluid model calculations, Yelle et al., (2008), Strobel (2009) and Cui et al. (2012) predicted a CH_4 escape rate at the level of ?10?^27 ? s?^(-1). Such a high value greater than the Jeans escape rate has been disputed by a number of authors. Describing the transition region of Titan’s atmosphere, Tucker & Johnson (2009) and Schaufelberger et al. (2012) show that the INMS data could be reproduced with a value similar with the Jeans escape rate by the Direct Simulation Monte Carlo (DSMC).

On the basis of the CH_4 emitted from Titan’s atmosphere, we simulate the escape process with the Jeans escape rate of 6.3×?10?^17 s^(-1) and calculate the methane-group (i.e., CH_4,CH_3, CH_2, CH and C) density distribution in the Saturn-Titan system by coupling the restricted three-body motion and the photochemical effects. In addition, we consider the double Maxwellian energy distribution contributed by a superthermal CH_4 population of (2-5)% on the high-energy tail, assuming two representative high CH_4 escape rates of 1.2×?10?^25 CH_4 s^(-1) and 2.2×?10?^27 CH_4 s^(-1) respectively (Jiang et al., 2017), and build two models in comparison with the original Jeans one.

All models suggest the methane-group densities peak between the orbit of Titan and the A ring. Gas clouds with high production rates and high-velocity population have more high density and extended distributions respectively. If the CH_4 escape rate calculation is correct, Titan is one of the major source of carbon. However, the Cassini Plasma Spectrometer (CAPS) has been no reported detection of carbon-containing ions in outer magnetosphere of Saturn commensurate with the compatible CH_4 torus (Johnson, 2009; Arridge et al., 2011). These observations reflect that fluid models may overestimate the CH_4 escape rate, or an extremely large chemical loss of carbon-containing ions due to dissociative mechanisms has not been found.
關鍵字(中) ★ 泰坦
★ 大氣逃逸
★ 軌道運動
關鍵字(英) ★ Titan
★ atmospheric escape
★ orbital motion
論文目次 目錄
摘要 ……………………………………………………………………… i
Abstract ……………………………………………………………………… ii
致謝 ……………………………………………………………………… iii
目錄 ……………………………………………………………………… iv
圖目錄 ……………………………………………………………………… v
表目錄 ……………………………………………………………………… v

第一章  概說…………………………………………………………………  1
  1-1 土星與土星環……………………………………………………… 1
  1-2  土衛六泰坦………………………………………………………… 3
  1-3  卡西尼任務的發現………………………………………………… 5
第二章 泰坦大氣的甲烷逃逸……………………………………………… 8
2-1  外球層基底與瓊斯逃逸…………………………………………… 8
2-2 甲烷的逃逸率……………………………………………………… 10
第三章 大氣逃逸模型……………………………………………………… 14
3-1 限制性三體運動…………………………………………………… 14
3-2 初始條件…………………………………………………………… 16
3-3 數值模擬法………………………………………………………… 18
3-4 逃逸過程…………………………………………………………… 22
第四章 模擬成果與討論…………………………………………………… 24
4-1 雙重馬克斯威爾分佈……………………………………………… 24
4-2 土星-泰坦系統內甲烷家族的密度分佈………………………… 26
第五章 總結………………………………………………………………… 34

參考文獻 ……………………………………………………………………… 36
參考文獻 Arridge, C.S., Andre, N., McAndrews, H.J., Bunce, E.J., Burger, M.H., Hansen, K.C., Hsu, H.W., Johnson, R.E., Jones, G.H., Kempf, S., Khurana, K.K., Krupp, N., Kurth, W.S., Leisner, J.S., Paranicas, C., Roussos, E., Russell, C.T., Schippers, P., Sittler, E.C., Smith, H.C., Thomsen, M.F., Dougherty, M.K., "Mapping Magnetospheric Equatorial Regions at Saturn from Cassini Prime Mission Observations", Space Sci. Rev., 164:1-83, 2011.
Bird, M. K., Dutta-Roy, R., Asmar, S. W., Rebold, T. A., “Detection
of Titan’s Ionosphere from Voyager 1 Radio Occultation Observations”, Icarus 130, 426–436, 1997.
Cui, J., Yelle, R. V., Strobel, D. F., Muller-Wodarg, I. C. F., Snowden, D. S., Koskinen, T. T., Galand, M, "The CH4 structure in Titan’s upper atmosphere revisited", J. Geophys. Res., 117, E11006, 2012.






Fulchignoni, M., Ferri, F., Angrilli, F., Ball, A.J., Bar-Nun, A., Barucci, M.A., Bettanini, C., Bianchini, G., Borucki, W., Colombatti, G., Coradini, M., Coustenis, A., Debei, S., Falkner, P., Fanti, G., Flamini, E., Gaborit, V., Grard, R., Hamelin, M., Harri, A.M., Hathi, B., Jernej, I., Leese, M.R., Lehto, A., Lion Stoppato, P.F., Lopez-Moreno, J.J., Makinen, T., McDonnell, J.A.M., McKay, C.P., Molina-Cuberos, G., Neubauer, F.M., Pirronello, V., Rodrigo, R., Saggin, B., Schwingenschuh, K., Seiff, A., Simoes, F. Svedhem, H., Tokano, T., Towner, M.C., Trautner, R., Withers, P., Zarnecki, J.C., “In situ measurements of the physical characteristics of Titan’s environment”, Nature 438, 785–791. doi:10.1038/nature04314, 2005.
Ingo, M.-W.,? Caitlin, A. G.,? Emmanuel, L.,? Thomas, E. C., “Titan: Interior, Surface, Atmosphere, and Space Environment”, Cambridge Planetary Science, 2013.
Ip, W.-H., “On the Neutral Cloud Distribution in the Saturnian Magnetosphere”, Icarus 126, 42-57, 1997.
Jiang, F., Cui, J., Xu, J., “The Structure of Titan’s N_2 and CH_4 Coronae”, Astrophys. J., 154:271, 2017.
Johnson, R. E., "Sputtering and heating of Titan′s upper atmosphere", Phil. Trans. R. Soc. A, 367, 753-771 2009.
Lembege, B., Eastwood, J. W., “Numerical Simulation of Space Plasmas”, Proceedings of the Third International School for Space Simulation: Tutorial Courses, 1987.
Michael, M., Johnson, R.E., “Energy deposition of pickup ions and heating of Titan’s atmosphere”, Planet. Space Sci. 53, 1510–1514, 2005.
Schaufelberger, A., Wurz, P., Lammer, H., Kulikov, Yu.N., "Is hydrodynamic escape from Titan possible?", Planetary and Space Science 61, 79-84, 2012.
Smith, B. A., "Encounter with Saturn: Voyager 1 imaging science results", Science, 212, 163, 1981.
Strobel, D.F., “Titan’s hydrodynamically escaping atmosphere”, Icarus 193, 588-594. 2008.
Strobel, D.F., “Titan’s hydrodynamically escaping atmosphere: Escape rates and the structure of the exobase region”, Icarus 202, 632-641, 2009.
Tadokoro, H., Misawa, H., Tsuchiya, F., Katoh, Y., Morioka, A., Yoneda M., “Effect of Photo-dissociation on the spreading of OH and O clouds in Saturn’s inner magnetosphere”, J. Geophys. Res., 117, A09226, 2012.


Tucker, O. J., Johnson, R. E., “Thermally driven atmosphere escape: Monte Carlo simulations for Titan’s atmosphere”, Planet. Space Sci. 57, 1889-1894, 2009.
Tomasko, M.G., Doose, L., Engel, S., Dafoe, L.E., West, R., Lemmon M., Karkoschka, E., See, C., “A model of Titan′s aerosols based on measurements made inside the atmosphere”, Planet. Space Sci. 56, 669–707, 2008.
Vervack, R. J., Jr., B. R. Sandel, and D. F. Strobel, "New perspectives on Titan’s upper atmosphere from a reanalysis of the Voyager 1 UVS solar occultations", Icarus, 170, 91– 112, 2004.
Yelle, R.V., Borggren, N., de la haye, V., Kasprzak, W. T., Niemann, H. B., Muller-Wodarg, I., Waite Jr., J.H., “The vertical structure of Titan’s upper atmosphere from Cassini Ion Neutral Mass Spectrometer measurements”, Icarus 182, 567-576, 2006.
Yelle, R.V., Cui, J., Muller-Wodarg, I. C. J., “Methane escape from Titan’s atmosphere”, J. Geophys. Res. 113, doi.10.1029/2007JE003031, 2008.
Yung, Y. L., "An updated of nitrile photochemistry on Titan", Icarus 72, 468-472, 1987.
指導教授 葉永烜(Wing-Huen Ip) 審核日期 2018-7-27
推文 facebook   plurk   twitter   funp   google   live   udn   HD   myshare   reddit   netvibes   friend   youpush   delicious   baidu   
網路書籤 Google bookmarks   del.icio.us   hemidemi   myshare   

若有論文相關問題,請聯絡國立中央大學圖書館推廣服務組 TEL:(03)422-7151轉57407,或E-mail聯絡  - 隱私權政策聲明