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arXiv 2407.02244astro-ph.SRphysics.space-ph
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探测内日冕日冕物质抛射内部的速度弥散:关于CME起始的新见解

Probing Velocity Dispersion inside CMEs in Inner Corona: New Insights on CME Initiation

Satabdwa Majumdar, Elke D' Huys, Marilena Mierla, Nitin Vashishtha, Dana-Camelia Talpeanu, Dipankar Banerjee, Martin A. Reiss

AI总结:

本研究首次在内日冕发现CME内部速度弥散的临界高度(1.4-1.8太阳半径),并揭示其与磁通量绳半径和CME质量相关,为理解CME起始机制提供新见解。

摘要:

本研究在太阳观测者使用有源像素系统探测器和图像处理(SWAP)搭载于在轨自主项目(PROBA-2)卫星上,以及地面莫纳罗亚太阳天文台(MLSO)的K-Cor日冕仪的联合视场内,研究了6个日冕物质抛射(CME)的前沿和核心的运动学。我们首次报道了临界高度h$_\mathrm{c}$的存在,该高度标志着CME内部速度弥散的起始。对于所研究的事件,该高度位于内日冕的1.4-1.8 R$_{\odot}$之间。我们发现,与脉冲型CME相比,渐进型CME的临界高度相对较高,表明这两类CME的早期起始可能在物理上有所不同。我们发现了速度弥散对CME运动学的几个有趣印记。临界高度与磁通量绳的小半径和CME的质量密切相关。此外,速度弥散的幅度与上述两个参数显示出合理的正相关。我们相信这些结果将增进我们对CME起始机制的理解,并将有助于为CME起始模型提供改进的约束。

英文摘要:

This work studies the kinematics of the leading edge and the core of 6 Coronal Mass Ejections (CMEs) in the combined field of view of Sun Watcher using Active Pixel System detector and Image Processing (SWAP) on-board PRoject for On-Board Autonomy (PROBA-2) and the ground-based K-Cor coronagraph of the Mauna Loa Solar Observatory (MLSO). We report, for the first time, on the existence of a critical height h$_\mathrm{c}$, which marks the onset of velocity dispersion inside the CME. This height for the studied events lies between 1.4-1.8 R$_{\odot}$, in the inner corona. We find the critical heights to be relatively higher for gradual CMEs, as compared to impulsive ones, indicating that the early initiation of these two classes might be different physically. We find several interesting imprints of the velocity dispersion on CME kinematics. The critical height is strongly correlated with the flux-rope minor radius and the mass of the CME. Also, the magnitude of velocity dispersion shows a reasonable positive correlation with the above two parameters. We believe these results will advance our understanding of CME initiation mechanisms and will help provide improved constraints to CME initiation models.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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