類型Ia超新星における環恒星物質は,ナトリウム吸収特性を介して超新星となる
A Sternberg1, A Gal-Yam, J D Simon
1Benoziyo Center for Astrophysics, Faculty of Physics, Weizmann Institute of Science, Rehovot 76100, Israel. assaf.sternberg@weizmann.ac.il
Science (New York, N.Y.)
|August 13, 2011
まとめ
宇宙距離測定に不可欠なタイプIa超新星は,単一の退化系から発生する可能性が高い. 証拠によると,これらの祖先系からガスの流出が示唆されており,近隣の多くの超新星についてこのモデルを支持しています.
科学分野:
- 天文学と天体物理学について
- コスモロジー・コスモロジーとは
- 恒星の進化について
背景:
- タイプIa超新星は,宇宙距離の重要な指標である.
- その起源は議論の的であり,主に単一変性 (星相伴星と白矮星の収束) と二重変性 (白矮星2つ) のモデルで論じられている.
- 祖先系における大量ドナーのアイデンティティは不明である.
研究 の 目的:
- タイプIア超新星の祖先系における質量ドナーの性質を調査する.
- 観察的証拠が単発性または双発性シナリオを支持するかどうかを判断する.
- タイプIア超新星の視線に沿って物質を吸収する特性を分析する.
主な方法:
- 35のタイプIア超新星の吸収物質の速度構造を分析した.
- ガス流出の指標としてブルーシフト速度構造を解釈した.
- 異なる祖先モデルの理論的予測と相関する観察された特徴.
主要な成果:
- 吸収物質の速度構造は,サンプル全体で主にブルーシフトでした.
- ブルーシフトによるガス流出は,超新星原始系から放出された物質と一致しています.
- 観測されたアウトフローは,単発退化系からのガス放出を含むシナリオを好む.
結論:
- 観測されたブルーシフト吸収特性は,原始システムからのガス流出を示唆しています.
- これらのアウトフローは,白矮星が非白矮星伴星から蓄積される単一退化系のサインである可能性が高い.
- 近隣の渦巻き銀河にある多くのタイプIア超新星は,単一退化した祖先から発生している可能性があります.
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