双离子成分下的赤道电离层R-T不稳定性

李彩云; 黄文耿

doi:10.11728/cjss2013.01.034

双离子成分下的赤道电离层R-T不稳定性

doi: 10.11728/cjss2013.01.034

中国科学院空间科学与应用研究中心北京 100190

基金项目: 国家重点基础研究发展计划项目资助(2011CB811406)

详细信息

中图分类号: P353
计量
- 文章访问数: 2692
- HTML全文浏览量: 51
- PDF下载量: 1053
- 被引次数: 0
出版历程
- 收稿日期: 2011-09-06
- 修回日期: 2012-11-28
- 刊出日期: 2013-01-15

Equatorial ionosphere Rayleigh-Taylor instability in the presence of double-ion species

Center for Space Science and Applied Research, Chinese Academy of Sciences, Beijing 100190

摘要

摘要: 等离子体R-T(Rayleigh-Taylor)不稳定性被认为是赤道夜间F区电离层产生不规则体的主要机制, 经典理论中只考虑了氧离子一种正离子成分, 等离子体R-T不稳定性的表达式与氧离子质量和密度无关. 事实上, 在有些情况下, 电离层F区往往不仅仅只有一种正离子存在. 本文利用连续性方程、动量方程和电流守恒方程, 采用微扰方法, 推导了双离子成分条件下, 赤道电离层R-T不稳定性线性增长率的表达式, 研究多种正离子成分对R-T不稳定性的影响. 结果表明, 双离子成分下线性增长率与两种正离子的数密度和质量都相关, 增长率的大小依赖于两种正离子成分所占的比例.
- R-T不稳定性 /
- 双离子 /
- 赤道扩展F /
- 增长率
Abstract: Plasma Rayleigh-Taylor instability plays a crucial role in the development of irregularities in the nocturnal equatorial ionosphere. In traditional theories, only the dominant element O⁺ is taken into consideration. As a result, the liner equation is independent with the ion mass and density. In fact, in some cases, there are not only one kind of positive ion in the F region of the ionosphere, such as in dusty plasma or in the ionospheric disturbances resulting from artificially chemical releases. It is essential to understand the effect of molecular ions in the collisional Rayleigh-Taylor instability. In this paper, a linear perturbation analysis associated with continuity equations, momentum equations and current conservation equation has been used to obtain a growth rate expression in the presence of double-ion species. The new expression reveals that the growth rate is dependent with the number densities and masses of both the ion elements, and especially, the proportions of the two kinds of ions contribute to growth rate.
- Rayleigh-Taylor instability /
- Double-ion /
- ESF /
- Growth rate

HTML全文

参考文献(22)

[1]	Groves K M, Basu S, Weber E J, et al. Equatorial scintillation and systems support[J]. Radio Sci., 1997, 32:2047-2064
[2]	Farley D T, Balsley B B, Woodman R F, et al. Equatorial spread F implication of VHF radar observations[J]. J. Geophys. Res., 1970, 75(34):7199-7216
[3]	Ossakow S L. Spread-F theories--A review[J]. J. Atmos. Terr. Phys., 1981, 43:437-443
[4]	Chaturvedi P K, Ossakow S L. Nonlinear theory of the collisional Rayleigh-Taylor instability in equatorial spread F[J]. Geophys. Res. Lett., 1977, 4:558-561
[5]	Hanson W B, Cragin B L, Dennis A. The effect of vertical drift on the equatorial F region region stability[J]. J. Atmos. Terr. Phys., 1986, 48:205
[6]	Huang C C, Kelly M C. Nonlinear evolution of equatorial spread F:gravity wave seeding of Rayleigh-Taylor instability[J]. J. Geophys. Res., 1996, 101:293
[7]	Sekar R, Raghavarao R. Role of vertical winds on the Rayleigh-Taylor mode instabilities of the nighttime equatorial ionosphere[J]. J. Atmos. Terr. Phys., 1987, 49:981
[8]	Zalesak S T, Ossakow S L, Chaturvedi P K. Nonlinear equatorial spread-F: The effect of neutral winds background Pedersen conductivity[J]. J. Geophys. Res., 1982, 87:151-166
[9]	Woodman R F. Vertical drift velocities and east-west electric fields at the magnetic equator[J]. J. Geophys. Res., 1970, 75:6249
[10]	Chiu Y T, Straus J M. Rayleigh-Taylor and wind driven instabilities of the night-time equatorial ionosphere[J]. J. Geophys. Res. 1979, 84:3283
[11]	Sekar R, Kelley M C. On the combined effects of vertical shear and zonal electric field patterns on nonlinear equatorial spread F evolution[J]. J. Geophys. Res., 1998, 103:20735-20747
[12]	Anderson D N, Rusch D W. Composition of the night-time ionospheric F₁ region near the magnetic equator[J]. J. Geophys. Res., 1980, 85:569
[13]	Sekar R, Kherani E A. Effects of molecular ions on the Rayleigh-Taylor instability in the night-time equatorial ionosphere[J]. J. Atmos. Solar-Terr. Phys., 1999, 61:399
[14]	Ossakow S L, Zalesak S T, Zalesak B E. Nonlinear equatorial spread F: dependence on altitude of the F peak and bottomside background electron density gradient scale length[J]. J. Geophys. Res., 1979, 84:17-29
[15]	Ossakow S L, Zalesak S T, Chaturvedi P K. Nonlinear equatorial spread F: The effects of neutral winds and background Pedersen conductivity[J]. J. Geophys. Res., 1982, 87:151-166
[16]	Narcisi R S, Szuszczewicz E P. Direct measurements of electron density, temperature and ion composition in an equatorial spread F ionosphere[J]. J. Atmos. Terr. Phys., 1981, 43:463
[17]	Luo Weihua, Xu Jisheng, Xu Liang. Analysis of controlling factors leading to the development of R-T instability in equatorial ionosphere[J]. Chin. J. Geophys., 2009, 52(4): 849-858. In Chinese (罗伟华, 徐继生, 徐良. 赤道电离层R-T不稳定性发展的控制因素分析[J]. 地球物理学报, 2009, 52(4):849-858)
[18]	Szuszczewicz E P. Tsunoda R T, Narcisi R, Holmes J C. Coincident radar and rocket observations of equatorial spread-F[J]. Geophys. Res. Lett., 1980, 7:537
[19]	Xie Hong, Xiao Zuo. Numerical simulation of spread F in low and mid-latitudes[J]. Chin. J. Geophys., 1993, 36(1):18-26. In Chinese (谢红, 肖佐. 中低纬Spread F的数值模拟[J]. 地球物理学报, 1993, 36(1):18-26)
[20]	Fukuyama A, Sen S, Honary F. Unstable Rayleigh-Taylor modes in the ionosphere in the presence of dusts[J]. Rad. Effects Defects Solids, 2010, 165:123-133
[21]	Huang Wengeng, Gu Shifen. Ionospheric disturbances produced by artificially chemical releases[J]. Chin. J. Space Sci., 2005, 25(4):254-258. In Chinese (黄文耿, 古士芬. 化学物质释放人工改变电离层[J]. 空间科学学报, 2005, 25(4):254-258)
[22]	Choueiri E Y, Oraevsky V N, Dokukin V S, et al. Observations and modeling of neutral gas releases from the APEX satellite[J]. J. Geophys. Res., 2001, 106:25673