在不同地磁风暴期间对等离子体β,Alfven马赫数和磁声马赫数的波形连贯性分析
Ashutosh Giri1, Binod Adhikari1, Rabin Baral2
1Department of Physics, St. Xavier's College, Tribhuvan University, Kathmandu, Nepal.
TheScientificWorldJournal
|July 4, 2024
概括
由CME或CIR驱动的地磁风暴表现出不同的等离子体行为. 等离子β和Alfven马赫数变化是预测G3强度以上风暴的关键指标.
科学领域:
- 空间物理 空间物理
- 等离子体物理学的物理学
- 地磁主义 地磁主义
背景情况:
- 地磁风暴是由太阳事件引发的,例如冠状质量喷射 (CME) 或旋转相互作用区域 (CIR).
- 了解太阳风等离子体行为对于预测地磁风暴影响至关重要.
- 主要的等离子体参数包括等离子体β,阿尔芬马赫数和磁声马赫数.
研究的目的:
- 分析在太阳周期23,24和25的地磁风暴期间等离子体β,Alfven马赫数和磁声马赫数的变化.
- 研究这些等离子体参数与地磁指数SYM-H.之间的关系.
- 为了确定风暴驱动机制 (CME与CIR) 是否影响等离子体参数行为和地磁活动.
主要方法:
- 使用的太阳风数据 (流压,质子密度,IMF Bz,温度,速度) 和地磁指数SYM-H.
- 采用波形连贯性 (WTC) 方法来分析等离子体参数和SYM-H之间的关系.
- 对CIR相关风暴和CME驱动风暴的等离子体参数变化进行比较.
主要成果:
- 与CIR相关的风暴表现出与阿尔芬马赫数和等离子β数上升相关的大幅度波;磁声马赫数显示的变化较小.
- CME驱动的风暴表现出不同的模式,磁共振马赫数的波动较小,相比阿尔芬马赫数和等离子体β.
- 在WTC分析中,SYM-H和等离子体参数之间的周期性 (64-512分钟) 显示出,在特定风暴事件 (例如,2004年11月,2015年6月) 中观察到显著的功率.
结论:
- 该研究强调了CME和CIR驱动的地磁风暴的独特等离子体动态.
- 等离子β,Alfven马赫数和磁声马赫数呈现出根据风暴起源的特征变化.
- 这些等离子体参数显示了超过G3强度的地磁风暴的预测潜力.
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