太陽に落下した噴火した断片による明るい熱い衝突:恒星増殖の模板
Fabio Reale1, Salvatore Orlando, Paola Testa
1Dipartimento di Fisica e Chimica, Università di Palermo, Piazza del Parlamento 1, 90134 Palermo, Italy. reale@astropa.unipa.it
Science (New York, N.Y.)
|June 22, 2013
まとめ
太陽にぶつかった太陽フレアの断片は,物質を蓄積する若い恒星に似た明るいスポットを作り出します. このプロセスは,高エネルギー放出と,観測された恒星増殖率の違いを説明します.
科学分野:
- 太陽物理 太陽物理学
- 天体物理学 天体物理学
- プラズマ物理学のプラズマ物理学
背景:
- 2011年6月7日の太陽フレアの観測は,太陽表面に衝突する落下した断片を明らかにした.
- これらの衝撃は,特に紫外線 (UV) と極紫外線の波長で,強烈でコンパクトな輝きを生み出しました.
- 観測された現象は,若い恒星物体の蓄積の流れに類似しています.
研究 の 目的:
- 太陽フレア中に落ちる断片によって生成される明るい斑点の背後にある物理的メカニズムを調査するために.
- これらの太陽現象を,若い恒星物体の蓄積過程と比較するために.
- 観測された高エネルギー排出量と質量増量速度測定における不一致を説明するために.
主な方法:
- ソーラーダイナミクス天文台の大気画像アセンブリからのUVと極紫外線画像データの分析.
- 太陽の表面に密度の高いプラズマが衝突する高解像度の水力力学シミュレーション.
主要な成果:
- シミュレーションにより,高密度のプラズマが太陽表面に高速で衝突すると,強烈な輝きが生じることが確認されました.
- これらの明るい斑点は,プラズマ温度が ~10^4 から ~10^6 ケルビンまで上昇することを表しています.
- 断片衝突による高エネルギー放射は,光学的に厚いプラズマによって大幅に吸収されます.
結論:
- 太陽フレア断片の衝突は,若い恒星における蓄積現象を模倣する.
- 高エネルギー放射のプラズマによる吸収は,UV光学近赤外線観測と比較して,X線データから推論されたより低い質量増量率を説明する可能性がある.
- この研究は,太陽フレアと若い恒星物体の蓄積円盤の両方で,高エネルギー現象に関する統一された視点を提供します.
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