DOI: 10.1002/2017JA025041
Scopus记录号: 2-s2.0-85046248463
论文题名: A Statistical Study of Spatial Variation of Relativistic Electron Precipitation Energy Spectra With Polar Operational Environmental Satellites
作者: Shekhar S. ; Millan R.M. ; Hudson M.K.
刊名: Journal of Geophysical Research: Space Physics
ISSN: 21699380
出版年: 2018
卷: 123, 期: 5 起始页码: 3349
结束页码: 3359
语种: 英语
英文关键词: EMIC waves
; energy spectrum
; magnetosphere
; radiation belts
; relativistic electrons
; space weather
英文摘要: The mechanisms that drive relativistic electron precipitation (REP) from the radiation belts can be better understood with a better knowledge of the particle energies involved. National Oceanic and Atmospheric Administration Polar Operational Environmental Satellites, being a network of multiple satellites, can provide multiple point spectral data over a long time period, including the Van Allen Probe's era. The number of energy channels is limited, but the particle detectors on Polar Operational Environmental Satellites have a narrow field of view allowing an investigation of bounce loss cone particles. We use the ratio of count rates in the E3 (>300 keV) and the P6 (>700 keV) channels as a parameter to define spectral hardness. Using this parameter, the spatial variation of spectral hardness of REP events was investigated. It was found that very soft events were mostly found in the dusk-midnight-early morning magnetic local time sectors and L∼ 5–7 while the hardest events were located in the postnoon sector peaking at L∼ 4–5. The hardest events peaked at lower L shells, and less than 20% were coincident with low-energy (30–80 keV) proton precipitation. Further, around 70% of nightside REP coincident with proton precipitation was associated with stretched magnetic field lines indicating that curvature scattering may have been an important driver. Around 62% of nightside REP coincident with proton precipitation associated with relaxed magnetic field lines, suggesting a mechanism other than magnetic field curvature scattering, was highly energetic. ©2018. American Geophysical Union. All Rights Reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/114009
Appears in Collections: 气候减缓与适应
There are no files associated with this item.
作者单位: Department of Physics and Astronomy, Dartmouth College, Hanover, NH, United States; High Altitude Observatory, Boulder, CO, United States
Recommended Citation:
Shekhar S.,Millan R.M.,Hudson M.K.. A Statistical Study of Spatial Variation of Relativistic Electron Precipitation Energy Spectra With Polar Operational Environmental Satellites[J]. Journal of Geophysical Research: Space Physics,2018-01-01,123(5)