Global S&T Development Trend Analysis Platform of Resources and Environment
DOI | 10.1029/2019GL085271 |
A New Substorm Onset Mechanism: Increasingly Parallel Pressure Anisotropic Ballooning | |
Oberhagemann, L. R.; Mann, I. R. | |
2020-01-28 | |
发表期刊 | GEOPHYSICAL RESEARCH LETTERS
![]() |
ISSN | 0094-8276 |
EISSN | 1944-8007 |
出版年 | 2020 |
卷号 | 47期号:2 |
文章类型 | Article |
语种 | 英语 |
国家 | Canada |
英文摘要 | Recent observations demonstrating that auroral beads are observed prior to the majority of substorm onsets (Kalmoni et al., 2017, ) have reinforced the potential importance of ballooning instabilities for near-Earth magnetospheric substorm onset. Here we examine pressure anisotropic ballooning instabilities in stretched magnetotail geometries. Our results show that transition from an initially perpendicular anisotropy toward parallel anisotropy reduces the plasma beta threshold for triggering a ballooning instability. Such increasingly parallel anisotropies can form as a direct consequence of tail stretching that occurs during the late substorm growth phase through the well-known effects of drift shell splitting and the competition between betatron and Fermi processes in the tail. We propose such increasingly parallel ballooning triggers auroral substorm onset on field lines in the transition region between dipolar and tail-like fields, consistent with observational constraints on the location of the onset arc with respect to the ion isotropy boundary in the magnetotail. |
英文关键词 | substorm ballooning instability auroral beads pressure anisotropy |
领域 | 气候变化 |
收录类别 | SCI-E |
WOS记录号 | WOS:000517154600004 |
WOS关键词 | CURRENT SHEET ; PLASMA ; INSTABILITY |
WOS类目 | Geosciences, Multidisciplinary |
WOS研究方向 | Geology |
引用统计 | |
文献类型 | 期刊论文 |
条目标识符 | http://119.78.100.173/C666/handle/2XK7JSWQ/279555 |
专题 | 气候变化 |
作者单位 | Univ Alberta, Dept Phys, Edmonton, AB, Canada |
推荐引用方式 GB/T 7714 | Oberhagemann, L. R.,Mann, I. R.. A New Substorm Onset Mechanism: Increasingly Parallel Pressure Anisotropic Ballooning[J]. GEOPHYSICAL RESEARCH LETTERS,2020,47(2). |
APA | Oberhagemann, L. R.,&Mann, I. R..(2020).A New Substorm Onset Mechanism: Increasingly Parallel Pressure Anisotropic Ballooning.GEOPHYSICAL RESEARCH LETTERS,47(2). |
MLA | Oberhagemann, L. R.,et al."A New Substorm Onset Mechanism: Increasingly Parallel Pressure Anisotropic Ballooning".GEOPHYSICAL RESEARCH LETTERS 47.2(2020). |
条目包含的文件 | 条目无相关文件。 |
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。
修改评论