在太阳附近探测能量粒子环境
D J McComas1, E R Christian2, C M S Cohen3
1Department of Astrophysical Sciences, Princeton University, Princeton, NJ, USA. dmccomas@princeton.edu.
Nature
|December 6, 2019
概括
美国宇航局的帕克太阳探测器观察到太阳附近的能量粒子,揭示了各种加速过程. 这些发现挑战了现有的太阳能粒子事件模型, 并改善了我们对太空天气的理解.
科学领域:
- * 天体物理学和空间等离子体物理学.
- 太阳能粒子 (SEP) 的加速和传输.
- * 内部日球和太阳冠状物理学.
背景情况:
- 太阳能粒子 (SEP) 通过"冲动" (太阳耀斑) 和"渐进" (冠状质量喷射) 事件加速.
- *以前的观测,大多在1个天文单位,面临的运输效应掩盖了接近太阳的加速物理.
- * 粒子特性上的差异表明超出了两种过程模型的复杂性.
研究的目的:
- 通过使用帕克太阳探测器的数据, 调查太阳附近的高能粒子辐射环境.
- 直接观察和分析太阳附近的SEP加速和运输机制.
- * 解决目前SEP加速模型中的模糊问题.
主要方法:
- * 帕克太阳探测器在最初的轨道上对能量粒子进行实地测量.
- *分析粒子事件特征,包括能量谱和组成.
- *粒子事件与太阳现象如耀斑和冠状物质喷射的相关性.
主要成果:
- 在太阳附近观测各种能量粒子事件,包括冲动和CME相关事件.
- * 有当地和远程加速过程的证据,包括旋转的相互作用区域.
- 直接来自内层日球的数据挑战了简单的SEP加速的两种过程模型.
结论:
- * 接近太阳的环境中存在各种SEP加速机制.
- 直接观测解决了了解粒子加速和传输的模两可.
- 这些发现为太阳附近的太阳能粒子提供了关键的见解.
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