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NGC 188の青い落後者にとっての質量移転の起源は,半太陽質量の同伴者によって明らかになりました
Aaron M Geller1, Robert D Mathieu
1Department of Astronomy, University of Wisconsin-Madison, Wisconsin 53706, USA. a-geller@northwestern.edu
Nature
|October 21, 2011
まとめ
NGC 188星団の青い落とし星には,太陽の質量の半分を重くする同伴星があります. この発見は,それらの起源として質量移転を支持し,恒星衝突を排除しています.
科学分野:
- 天文学 天文学
- 天体物理学 天体物理学
- 恒星の進化について
背景:
- ブルー・ストラグラー星は,開いた星団では予想以上に明るく,青くなります.
- その形成は議論されており,二重質量移動,合併,恒星衝突などの仮説が提唱されている.
研究 の 目的:
- 古い開いた星団NGC188の青い落とし子星の起源を調査する.
- 星の衝突と質量移転/合併のシナリオを区別するために.
主な方法:
- NGC 188星団内の長周期バイナリーの青い滞留者の分析.
- 伴星質量とその分布の決定.
主要な成果:
- NGC 188のブルー・ラグラーズには,太陽の半分ほどの質量を持つ同伴者がいます.
- 伴侶の狭い質量分布は,恒星衝突の起源を排除しています.
- 階層的なトリプルスターでの合併は,わずかにしか支持されていません.
結論:
- 観測された同伴の質量は,これらの青い滞留者にとって支配的な形成機構としての質量移転を強く支持しています.
- 仲間は,太陽の質量の約半分を持つ白矮星である可能性が高い.
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