地球磁氣圈內磁重聯現象之流體粒子混成模型

Hybrid Model of Magnetic Reconnection in Earth Magnetosphere

黃子娟(Tzu-Chuan Huang)

指導教授 ： 江簡富

國立臺灣大學/電機資訊學院/電信工程學研究所/碩士(2016年)

https://doi.org/10.6342/NTU201610039

摘要

當具有南向星際磁場的太陽吹至地球時，在地球磁氣圈內可能導致磁重聯現象，其具體表徵為X-line的顯現。離子擴散層位於X-line的中心，在離子擴散層中，磁場的磁能會被轉換成質子的動能，將質子加速。本論文使用二維流體粒子混成模型模擬地球磁氣圈的磁重聯現象，在此模型中，電子被視為連續流體，而質子被視為離散粒子。文中分析磁場擾動、電流層厚度以及離子與電子質量比對磁場重聯率的影響。最後並使用磁氣圈內的Cluster太空船在2001年9月10日觀測到的數據驗證此模型。

關鍵字

磁場重聯 ； 流體粒子混成模型 ； 離子擴散層 ； 磁場重聯率

並列摘要

Magnetic reconnections were observed in the magnetotail when a southward interplanetary magnetic field (IMF) blows toward the Earth. Protons will be accelerated in an ion diffusion region (IDR) near the center of the X-line, and the magnetic energy in the field will be converted to increase the kinetic energy of the protons. Magnetic reconnection in the magnetotail is simulated with a two-dimensional hybrid model, in which electrons are treated as fluid and ions are treated as particles. The effects of magnetic field perturbation, current-sheet width and ion-to-electron mass ratio on the reconnection rate are analyzed. The parameters extracted from the data measured with the Cluster spacecraft in the magnetotail on September 10, 2001, are also used to check the validity of this model.

並列關鍵字

magnetic reconnection ； hybrid model ； ion diffusion region ； reconnection rate

參考文獻

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