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アシンプトティック・ジャイアント・ブランチにある恒星からの分子ガスのコリマートジェット
Hiroshi Imai1, Kumiko Obara, Philip J Diamond
1VERA Project Office, National Astronomical Observatory, Mitaka, Tokyo 181-8588, Japan. imai@jive.nl
Nature
|June 21, 2002
まとめ
天文学者は,星W43A.から分子ガスのコリマート,プレセッシングジェットを検出しました. この発見は,恒星が遷移期に延長された惑星星雲を形成する方法を説明しています.
科学分野:
- 天文学と天体物理学について
- 恒星の進化について
- アストロケミストリー アストロケミストリー
背景:
- 進化した星 (約. 1太陽質量) は,典型的には球形である.
- 惑星性星雲は,球形の対称性ではなく,しばしば不対称性を表します.
- コリマートジェットとアウトフローは惑星の星雲で観察され,不対称性の説明としてプレセッションが提案されています.
研究 の 目的:
- 惑星の星雲における非対称性の起源を調査する.
- 惑星性星雲のコリマートジェットの背後にあるメカニズムを決定する.
- ジェット形成の理論的モデルのための観察的証拠を提供する.
主な方法:
- 水蒸気マザースポットを用いて分子ガスの検出.
- 星W43A.から約500天文学単位 (au) のジェットが観測された.
- ジェットコリマーションとプレセッションの分析.
主要な成果:
- 分子ガスのコリマート・プレセッシング・ジェットの検出.
- ジェットは,星W43A.の近くの水蒸気マザースポットによって追跡されます.
- ジェットは,中央の星に近いところから発生します.
結論:
- 観測されたジェットは,星のすぐ近くで形成されています.
- 長方形の惑星星雲は,おそらくそのようなジェットによって形成されています.
- このプロセスは,短い原惑星性星雲期 (1000年未満) で起こります.
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