太陽の噴火につながる磁気環境の特徴と予測
Tahar Amari1, Aurélien Canou1, Jean-Jacques Aly2
1Centre de Physique Théorique, Ecole Polytechnique, CNRS, F-91128 Palaiseau Cedex, France.
Nature
|October 25, 2014
まとめ
冠状体の質量放出は,歪んだ磁気流のロープによって動かされ,不安定になります. 私たちのモデリングは,光球磁場から形成され成長するこれらのフルスロープが,磁気エネルギーが均衡を超えるとエジェクションにつながることを示しています.
科学分野:
- 太陽物理 太陽物理学
- マグネトヒドロダイナミクス
- 宇宙天気は,宇宙の天気です.
背景:
- 冠状質量噴射 (CME) を駆動する物理的メカニズムは,太陽の低い冠状の3D磁場を観察する上で課題があるため,依然として不確実です.
- 2つの主要なモデルが存在します:噴火中のアーケード再接続によるフルスロープの不安定性とフルスロープ形成です.
研究 の 目的:
- 計算モデリングを使用して冠状管質量放出の原因となる物理的メカニズムを調査する.
- CMEのフクスロープ不安定性モデルに観測およびモデリングのサポートを提供すること.
主な方法:
- CMEの4日前の観測された光球磁場データを,磁場構成モデリングの境界条件として利用した.
- 噴火前の磁場を準静的溶液として処理し,ゆっくりとした進化を可能にしました.
- 噴火条件をシミュレートするために,フルスキャンセルなどの光球の変化下でモデルを動的に進化させた.
主要な成果:
- フルスロープの形成と成長がモデル化され,噴火までの数日間に,自由な磁気エネルギーの増加が特徴です.
- 蓄積された磁気エネルギーが均衡の限界を超えると,フルスロープが不安定になり,射出されると実証されました.
- この不安定性に関連した後の磁気再接続が,質量放出を駆動していることを確認しました.
結論:
- この研究は,冠状質量放出のためのフルスロープ不安定性モデルを支持する強力なモデリングの証拠を提供します.
- この発見は,CMEの開始において,既にある,進化する磁気流動ロープの重要な役割を強調している.
- この研究は,強力な太陽噴火や宇宙天候現象を制御する基本的な物理学の理解を前進させる.
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