...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Geophysical Research, A. Space Physics: JGR >Radiation belt electron precipitation into the atmosphere: Recovery from a geomagnetic storm
【24h】

Radiation belt electron precipitation into the atmosphere: Recovery from a geomagnetic storm

机译：辐射带电子降水进入大气:康复地磁风暴

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Large geomagnetic storms are associated with electron population changes in the outer radiation belt and the slot region, often leading to significant increases in the relativistic electron population. The increased population decays in part through the loss, that is, precipitation from the bounce loss cone, of highly energized electrons into the middle and upper atmosphere (30–90 km). However, direct satellite observations of energetic electrons in the bounce loss cone are very rare due to its small angular width. In this study we have analyzed ground-based subionospheric radio wave observations of electrons from the bounce loss cone at L = 3.2 during and after a geomagnetic disturbance which occurred in September 2005. Relativistic electron precipitation into the atmosphere leads to large changes in observed subionospheric amplitudes. Satellite-observed energy spectra from the CRRES and DEMETER spacecraft were used as an input to an ionospheric chemistry and subionospheric propagation model, describing the ionospheric ionization modifications caused by precipitating electrons. We find that the peak precipitated fluxes of >150 keV electrons into the atmosphere were 3500 ± 300 el cm?2 s?1 at midday and 185 ± 15 el cm?2 s?1 at midnight. For 6 d following the storm onset the midday precipitated fluxes are approximately 20 times larger than observed at midnight, consistent with observed day/night patterns of plasmaspheric hiss intensities. The variation in DEMETER observed wave power at L = 3.2 in the plasmaspheric hiss frequency band shows similar time variation to that seen in the precipitating particles. Consequently, plasmaspheric hiss with frequencies below ～500 Hz appears to be the principal loss mechanism for energetic electrons in the inner zone of the outer radiation belts during the nonstorm time periods of this study, although off-equatorial chorus waves could contribute when the plasmapause is L < 3.0.
机译：大地磁风暴与相关联外层电子人口变化辐射带和槽区域,通常领先在相对论显著增加电子的数量。衰变中损失,的反射损失锥,沉淀高能量电子进入中产和高层大气(30 - 90公里)。卫星观测的高能电子反弹损失锥由于其非常罕见小角宽度。分析了地面subionospheric无线电波观察电子的反射损失锥地磁L = 3.2期间和之后扰动发生在2005年9月。相对论电子降水进入大气中导致观察到的巨大变化subionospheric振幅。退休研究中心的能量谱和得墨忒耳飞船被用作一个一个的输入电离层化学和subionospheric传播模型,描述了电离层电离的修改由沉淀造成的电子。通量> 150 keV电子到大气中是3500±300 el厘米?15 el厘米?风暴开始中午沉淀通量观察到约20倍午夜,符合观察白天/黑夜plasmaspheric嘘强度的模式。得墨忒耳的变化观察波浪发电L =3.2 plasmaspheric嘶嘶声频段显示了类似的时间变化的沉淀颗粒。plasmaspheric嘶嘶声频率低于~ 500赫兹似乎是本金损失的机制高能电子的内部区域在nonstorm时间外辐射带本研究时期,尽管off-equatorial合唱时可以提供等离子体层顶是L < 3.0。

著录项

相似文献

  • 外文文献
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号