| 项目编号: | 1207445
|
| 项目名称: | Multipoint Observations of Compressional Pulsations: Testing Possible Generation Mechanisms |
| 作者: | Galina Korotova
|
| 承担单位: | University of Maryland College Park
|
| 批准年: | 2013
|
| 开始日期: | 2014-09-01
|
| 结束日期: | 2018-08-31
|
| 资助金额: | USD300000
|
| 资助来源: | US-NSF
|
| 项目类别: | Continuing grant
|
| 国家: | US
|
| 语种: | 英语
|
| 特色学科分类: | Geosciences - Atmospheric and Geospace Sciences
|
| 英文关键词: | mechanism
; wave
; compressional pulsation
; compressional wave
; themis observation
; cluster observation
; pulsation
; compressional pc
|
| 英文摘要: | The ultra-low frequency (3 to 15 minute periods) electromagnetic waves called Pc 5 pulsations have been studied for over 50 years. They are an important magnetospheric phenomenon because they convert energy from one form to another and transmit energy from one location to another. Although there have been a number of physical explanations proposed for these waves their origin remains unknown. This proposal seeks to determine the origin of one class of these waves ? compressional Pc 5 pulsations. The Principal Investigator of this proposal will be assisted by a graduate student in carrying out this research protocol.
These are waves in the Pc 5 frequency range for which there are oscillations along the direction of the background magnetic field. Three mechanisms have been proposed for these waves: drift mirror instabilities due to pressure anisotropies, drift bounce instabilities and injection of blobs of plasma sheet plasma into the inner magnetosphere. The combination of THEMIS observations near the equator and Cluster observations in polar orbit now makes it possible to determine which of these mechanisms are operating.
The following questions have been identified for study:
1. What mechanism generates compressional pulsations in the dawn and dusk magnetosphere?
2. What are the characteristics of the compressional pulsations, including their spatial extent and latitudinal structure?
3. What mechanism generates the subcategory of compressional waves exhibiting frequency doubling (the frequency of the compression component of the waves is twice that of the transverse components) and how do suprathermal particles respond to the pulsations? |
| 资源类型: | 项目
|
| 标识符: | http://119.78.100.158/handle/2HF3EXSE/95857
|
| Appears in Collections: | 影响、适应和脆弱性
气候减缓与适应
|
|
There are no files associated with this item.
|
| Recommended Citation: | |
Galina Korotova. Multipoint Observations of Compressional Pulsations: Testing Possible Generation Mechanisms. 2013-01-01.
|
|
|