在范·艾伦辐射带中对超相对论电子构成不可穿透的屏障
D N Baker1, A N Jaynes1, V C Hoxie1
1Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80303, USA.
Nature
|November 28, 2014
概括
范·艾伦辐射带的辐射带.
科学领域:
- 太空物理空间物理学
- 血物理学的等离子体物理学
- 地质物理学 地质物理学
背景情况:
- 地球的范艾伦辐射带以高能粒子的内部和外部区域为特征.
- 一个"槽"区域通常将这些区域分开,中等能量的电子填充了两者.
- 等离子区间,等离子球的外界,已与辐射带结构联系起来.
研究的目的:
- 为了研究辐射带的意想不到的形态,特别是在超相对论能量.
- 为了确定观察到超相对论电子的尖内界的原因.
- 了解限制能量电子向内辐射传输的机制.
主要方法:
- 对一个扩展的辐射带观测数据集的分析.
- 检查对粒子运输和波相互作用同时测量的数据.
- 在等离子体中模拟粒子扩散和散射过程.
主要成果:
- 对于范艾伦带中的超相对论电子,确定了一个极其利的内部边界.
- 这一边界不是由物理磁场边界或发射波场造成的.
- 异常缓慢的向内辐射扩散和持续的波粒子散射会给能量电子迁移带来障碍.
结论:
- 外部辐射区域的尖内界是动态特征,而不是静态磁场极限.
- 自然过程,特别是缓慢的扩散和微弱的散射,对观察到的电子屏障负责.
- 了解这些机制对于预测地球辐射带的行为至关重要.
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