...
  • 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 >Statistics of intense dawn-dusk currents in the Earth's magnetotail
【24h】

Statistics of intense dawn-dusk currents in the Earth's magnetotail

机译：统计的dawn-dusk电流地球磁尾

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

We consider Cluster observations of events with an intense current density (> 5 nA/m~2) in the magnetotail current sheet. We use measurements by Cluster mission in the central magnetotail (X 300 km/s). We introduce the parameter v_D∕v_(Ti) (where v_D = j_y∕en_e, n_e is an electron density, and vTi is a proton thermal velocity) and show that cases with v_D∕v_(Ti) ～1 correspond to the most intense currents observed in the vicinity of the reconnection regions. The comparison of electron and proton velocities demonstrates that electron often carry almost the entire current measured by a curlometer technique. The strong electron temperature anisotropy T_(e∥)∕T_(e⊥) >1.2 corresponds to large magnitudes of B_y component of the magnetic field. We conclude that intense current sheets are often characterized by significant (more than 30%) contribution of electron curvature currents to the cross-tail current. The comparison of observations and models shows that the electron anisotropy level is likely controlled by competition of two processes: the electron scattering on fluctuations generated by fire-hose instability and the acceleration in sheared magnetic field configurations. We also suggest that current sheets embedded into the strong plasma flows (v_x∕v_(Ti) > 0.1) can be balanced by ion flow anisotropy.
机译：我们考虑集群事件的观察强烈的电流密度(> 5 nA / m ~ 2)当前磁尾单。在中央磁尾(X 300 km / s)。我们介绍了参数v_D∕v_ (Ti) (v_D= j_y∕en_e, n_e电子密度,和vTi是一个质子热速度)和显示用例与v_D∕v_ (Ti) ~ 1对应于最激烈水流观察附近的重新连接区域。电子和质子的速度表明经常带着几乎整个当前衡量curlometer技术。各向异性温度T_ (e∥)识别∕T_ (e⊥)识别> 1.2对应于大的话组件的大小的磁场。当前表通常的特征重要的(30%以上)的贡献电子曲率cross-tail电流电流。模型表明,电子各向异性程度可能是由两个竞争过程:电子散射消防水龙带所产生的波动不稳定和加速度剪切磁场配置。表嵌入到强大的等离子体流(v_x∕v_ (Ti) > 0.1)可以通过离子平衡流动各向异性。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
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