マクニールの星雲を照らす,急速に収縮している若い星からのX線爆発
J H Kastner1, M Richmond, N Grosso
1Rochester Institute of Technology, Rochester, New York 14623-5604, USA. jhk@cis.rit.edu
Nature
|July 23, 2004
まとめ
若い恒星は強力なX線フレアを発し,惑星形成に影響を与える可能性があります. 蓄積現象は,X線放射を著しく増幅し,初期の恒星系発達に潜在的に影響を与える.
科学分野:
- * 天体物理学 * 天体物理学
- * 恒星の進化について
- * 惑星系外惑星の研究
背景:
- *若い低質量恒星は,明るいX線源である.
- *これらの恒星からのX線フレアが惑星形成に影響を与える可能性がある.
- *X線放射の起源 (冠状の活動と蓄積) は議論されている.
研究 の 目的:
- *若い恒星のX線放射の起源を調査する.
- * 質量増積がX線光度に影響するかどうかを判断する.
- * 蓄積爆発とX線フレアとの関係を研究する.
主な方法:
- *X線画像スペクトロスコピーの観測.
- * 光学/赤外線爆発中の若い星の監視.
- *X線流量変化の分析.
主要な成果:
- *若い恒星からのX線流の50倍の増加を観測した.
- *X線波は壮大な光学/赤外線爆発と一致しました.
- * 爆発は,恒星に急速な質量蓄積が起因していると考えられた.
結論:
- * 高い蓄積率は,若い恒星からの高エネルギー放射を強く強化する原因となる.
- * 収縮強化X線放射は,短期的な現象である可能性が高い.
- * 強い恒星円盤の相互作用は,物質の流入によって急速に消える.
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