在现场观测大幅度的阿尔夫恩波加热和加速太阳风
Yeimy J Rivera1, Samuel T Badman1, Michael L Stevens1
1Center for Astrophysics, Harvard and Smithsonian, Cambridge, MA 02138, USA.
概括
由帕克太阳探测器和太阳轨道器观测到的大幅度阿尔夫恩波被发现足以加热和加速太阳风的内部日球,挑战了以前的预期.
科学领域:
- 太空物理
- 血物理
- 太空物理学
背景情况:
- 太阳风在离开太阳冠后加速和冷却,但其速度比自由膨胀的亚底气体预测的要慢.
- 阿尔夫恩波是行星间磁场的扰动, 已知能运输能量.
研究的目的:
- 研究阿尔夫恩波在太阳风的加热和加速中所起的作用.
- 分析穿越该地区的空间飞船的现场测量结果.
主要方法:
- 使用来自帕克太阳探测器和太阳轨道飞船的现场测量.
- 观测太阳风在太阳层内移动的特定流.
主要成果:
- 观测证实了冠冕边缘与金星轨道之间的等离子体加热和加速.
- 在该区域内检测到大振幅的阿尔夫恩波.
- 计算表明这些波的阻尼和机械作用足以驱动所观察到的太阳风现象.
结论:
- 阿尔夫恩波缓和和机械工作足以解释太阳内部快速风的加热和加速.
- 这些发现为推动太阳风在太阳附近演变的能量转移提供了机制.
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