小規模なダイナモ磁気は,太陽の大気の加熱の原動力として働いています

Tahar Amari¹, Jean-François Luciani¹, Jean-Jacques Aly²

¹Centre de Physique Théorique, Ecole Polytechnique, CNRS, F-91128 Palaiseau Cedex, France.

Nature

|June 12, 2015

まとめ

太陽の大気の加熱は,クロモスフィアの熱プラズマの小さな噴火を示す新しいモデルによって説明されています. これらの噴火は下部コロナに到達し,アルフヴェン波は上部コロナを熱します.

科学分野:

太陽物理太陽物理学
プラズマ物理学のプラズマ物理学
天体物理学天体物理学

背景:

太陽の大気の加熱メカニズムは,長年の問題であり続けています.
以前の研究では,磁気再接続と波が強調され,染色球-コロナ相互作用が強調されました.
染色球現象によって冠状の加熱を説明する完全に一貫したモデルは,まだ欠けている.

研究の目的:

静かな太陽の大気の加熱をモデル化するために.
サブフォトスフィアの磁場発生とクロモスフィアの噴火の役割を調査する.
アルフヴェン波の冠状熱への貢献を理解するために.

主な方法:

顆粒化に結びついた亜光球流体ダイナモを介して磁場生成のモデルを開発した.
磁場がクロモスフィアに膨張し,プラズマが加熱されるシミュレーションを行いました.
垂直ネットワークの磁場の効果とアルフヴェン波の分散を組み込みました.

主要な成果:

モデルは,磁気エネルギーを放出し,音速運動を誘発する小規模な噴火を通じて染色球のプラズマ加熱 (4,500 W/m2) を再現しています.
エネルギーに満ちた噴火は1000万mの高さに達し,低層のコロナに影響を及ぼした.
クロモスフィアで生成されるアルフヴェン波は,冠状の加熱に必要なエネルギーフックスを (300W/m2) 運ぶ.
このモデルは,複雑な表面磁場 (160ガウス) を予測し,スパイキュル,点滅器,太陽竜巻のような特徴を備えている.

結論:

小規模な染色球噴火は染色球の加熱に不可欠であり,低いコロナに影響を与える可能性があります.
クロモスフィアから発生するアルフヴェン波は,コロナの加熱のための有効なメカニズムを提供します.
このモデルは,太陽の大気加熱を理解するための一貫した枠組みを提供し,サブフォトスフィアのプロセスをクロモスフィアおよびコロナ現象と統合しています.

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