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A 100 KW Class Applied-field Magnetoplasmadynamic Thruster
Published on: December 22, 2018
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作为太阳大气层加热的驱动力,小规模的磁力发电机磁力
Tahar Amari1, Jean-François Luciani1, Jean-Jacques Aly2
1Centre de Physique Théorique, Ecole Polytechnique, CNRS, F-91128 Palaiseau Cedex, France.
Nature
|June 12, 2015
概括
太阳大气的升温是由新的模型解释的,这些模型显示了染色体热等离子体中的小喷发. 这些喷发可以到达低冠状,而阿尔夫恩波可以加热高冠状.
科学领域:
- 太阳物理 太阳物理
- 血物理学的等离子体物理学
- 天体物理学 天体物理学
背景情况:
- 太阳大气层的加热机制仍然是一个长期存在的问题.
- 之前的研究强调了磁再连接和磁波,强调了染色体 - 冠状元相互作用.
- 仍然缺乏一个完全一致的模型,通过染色体现象来解释冠状热.
研究的目的:
- 为了模拟平静的太阳大气层的升温.
- 为了研究亚光球磁场生成和色球爆发的作用.
- 了解阿尔夫文波对冠状热的贡献.
主要方法:
- 通过与颗粒结合的亚光球流体动力发电机开发了一种磁场生成模型.
- 模拟磁场扩展到染色体和随后的等离子体加热.
- 结合了垂直网络磁场和阿尔夫恩波散射的影响.
主要成果:
- 该模型通过小规模的喷发重现了染色体等离子体加热 (4,500 W/m2),释放磁能并驱动声波运动.
- 观察到能量喷发达到1000万米的高度,影响了低冠状.
- 在染色体中产生的阿尔弗温波携带所需的能量流 (300 W/m2) 进行冠状热.
- 该模型预测了复杂的表面磁场 (160高斯) 和类似于尖头,闪光灯和太阳龙卷风的特征.
结论:
- 小规模的染色层喷发对于加热染色层至关重要,并且可以影响低冠状.
- 来自染色体的阿尔弗文波提供了一个可行的加热冠状的机制.
- 该模型为了解太阳大气加热提供了一个一致的框架,将亚光球过程与染色球和冠状现象集成在一起.
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