太陽の重力モードを追跡する: 太陽の核の動態

Rafael A García¹, Sylvaine Turck-Chièze, Sebastian J Jiménez-Reyes

¹DSM/DAPNIA/Service d'Astrophysique, CEA Saclay, 91191 Gif-sur-Yvette Cedex, France. rafael.garcia@cea.fr

Science (New York, N.Y.)

|May 5, 2007

まとめ

科学者たちは,低周波グローバル振動器を用いて,太陽の核を探査するために不可欠な太陽重力モードを検出しました. 分析は,これまでモデル化されていたよりも,より速いコア回転を示唆している.

科学分野:

*ヘリオ地震学と太陽物理学.
* 恒星の構造と進化.
* 太陽の内部ダイナミクス.

背景:

* 太陽の重力モードは,太陽の核を理解するために不可欠ですが,表面の振幅が小さいため検出が困難です.
* 太陽のこれらのモードを検出する以前の試みは,無結論でした.
* 音響モードは,太陽の外層と全体的な物理学の洞察を提供します.

研究の目的:

* 太陽重力の二極モードの最初の決定的な検出を達成するために.
* 太陽の中心内の自転速度を調査する.
* 太陽の内部構造と動力のモデルを精査する.

主な方法:

* 全球低周波振動 (GOLF) 計器からのデータを使用した.
*重力二極モードを示す周期構造のデータを分析した.
* 観測データを,音響モード解析に基づく太陽内部のシミュレーションと比較した.

主要な成果:

* 重力二極モードの理論的予測と一致する周期構造が検出されました.
*検出された信号の特徴は,これらの難解なモードの存在を裏付けている.
* 確立された太陽物理を組み込んだシミュレーションは,太陽の核のより速い回転率を示唆しています.

結論:

*この発見は,太陽重力二極モードの検出のための強力な証拠を提供します.
*この結果は,太陽の核が,音響モードのみに基づいたモデルによって予測されたより速く回転することを示唆しています.
* この発見は,太陽の核を直接探査し理解するための新しい道を開きます.

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