Multispacecraft and ground-based observations of substorm timing and activations: Two case studies

	Multispacecraft and ground-based observations of substorm timing and activations: Two case studies
	Cao, X.1; Pu, Z. Y.1,19; Zhang, H.1; Mishin, V. M.14; Ma, Z. W.13; Dunlop, M. W.4; Fu, S. Y.1; Xie, L.1 ; Xiao, C. J.17; Wang, X. G.16
刊名	JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
	2008-05-21
卷号	113 期号:A7
英文摘要	Two case studies are performed to investigate substorm timing and activations based on Double Star TC1, Cluster, Polar, IMAGE, LANL geostationary satellites and ground-based geomagnetic field measurements. In both events, an earthward flow associated with plasma sheet thinning is measured by Cluster 8-10 min ahead of the auroral breakup. A couple of minutes after the breakup, either TC1 at similar to X-10 R(E) first detects plasma sheet expansion and then the LANL satellites near the midnight measure energetic electron injections at geostationary orbit or the LANL satellites first measure the electron injections and then TC1 detects the plasma sheet expansion. More than about 20 min later, Cluster at X similar to 16 R(E) and Polar (at higher latitude) successively observe plasma sheet expansion. The open magnetic flux of the polar cap, Psi, is found to continually increase during the early substorm phase and then to rapidly fall when the IMF turns northward. When Psi reaches its minimum value, bright and broad auroral activities start to decrease. Tailward progression of the magnetic dipolarization and a poleward expansion of auroral bulges are shown to closely map to one another. These results suggest that substorm activations start in the midtail before ground onset and then move earthward, which leads to an expansion onset in the near- Earth tail around X similar to-(8-9) R(E). After onset, the activations progress both earthward and tailward. Substorm onset is possibly related to plasma sheet reconnection of close field lines, while tail lobe reconnection of open field lines release more energy to support the full expansion of the substorm. In a fully developed expansion phase, an initial dipolarization in the near- Earth may eventually evolve to enable disruption of the cross-tail current over a wide region of the magnetotail.
收录类别	SCI
语种	英语
WOS记录号	WOS:000256142100001
内容类型	期刊论文
源URL	[http://ir.bao.ac.cn/handle/114a11/7432]
专题	国家天文台_太阳物理研究部
作者单位	1.Peking Univ, Sch Earth & Space Sci, Beijing 100871, Peoples R China 2.Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London SW7 2AZ, England 3.Ctr Etud Spatiale Rayonnements, F-31028 Toulouse 4, France 4.Rutherford Appleton Lab, Space Sci & Technol Dept, Chilton OX11 0QX, England 5.European Space Agcy, Estec, NL-2200 AG Noordwijk, Netherlands 6.UCL, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England 7.Max Planck Inst Solar Syst Res, D-37191 Katlenburg Lindau, Germany 8.Los Alamos Natl Lab, Los Alamos, NM 87545 USA 9.Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA 10.Tech Univ Carolo Wilhelmina Braunschweig, IGM, D-38106 Braunschweig, Germany
推荐引用方式 GB/T 7714	Cao, X.,Pu, Z. Y.,Zhang, H.,et al. Multispacecraft and ground-based observations of substorm timing and activations: Two case studies[J]. JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS,2008,113(A7).
APA	Cao, X..,Pu, Z. Y..,Zhang, H..,Mishin, V. M..,Ma, Z. W..,...&Escoubet, C. P..(2008).Multispacecraft and ground-based observations of substorm timing and activations: Two case studies.JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS,113(A7).
MLA	Cao, X.,et al."Multispacecraft and ground-based observations of substorm timing and activations: Two case studies".JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS 113.A7(2008).