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来自GOES数据30年的Pc5 ULF波的发生特征和振幅频率关系
Fadil Inceoglu1,2, Paul T M Loto'aniu3,4
1Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, Boulder, CO, USA. fadil.inceoglu@colorado.edu.
Scientific reports
|October 21, 2025
概括
这项研究揭示了Pc5超低频 (ULF) 波是由太阳风压力和凯尔文-赫尔姆霍尔茨不稳定性驱动的,其发生率与太阳周期和准双年振荡 (QBOs) 相关. 这些发现改善了空间天气预报和辐射带动态的理解.
科学领域:
- * 空间物理 空间物理
- * * 地质物理学
- * 等离子体物理学
背景情况:
- * Pc5超低频 (ULF) 波是地球磁层中的重要现象.
- * 之前的研究显示,在理解ULF波特征和驱动因素方面存在差异.
- * 长期分析对于识别太阳周期和其他调节至关重要.
研究的目的:
- * 调查Pc5 ULF波的发生特征和振幅频率关系.
- * 确定ULF波活动的主要驱动因素和依赖因素.
- * 解决先前研究中的差异,并改进空间天气模型.
主要方法:
- *利用了30年的GOES磁场数据 (1995-2025年).
- *采用了增强的CLEAN算法,用于在平均场对齐坐标中识别波事件.
- *分析了振幅-频率关系和与太阳风参数和太阳周期的相关性.
主要成果:
- *确定了27,279个辐射,26,145个亚齐图斯和31,259个平行ULF波事件.
- * 辐射波和平行波在9-15MLT (太阳风压) 达到峰值,亚齐图斯波和平行波在15-21MLT (凯尔文-赫尔姆霍尔茨不稳定) 达到峰值.
- *观察到强烈的功率规律振幅频率关系,根据太阳风条件和MLT部门而异;发生在太阳最大值期间达到峰值,并显示近两年一次的振荡 (QBOs).
结论:
- * ULF波动力学是由太阳周期,QBO和MLT依赖驱动器的组合形成的.
- * 结果澄清了ULF波生成机制和依赖关系,解决了之前的差异.
- *结果对理解辐射带动力学和增强太空天气预报有重大影响.
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