密集した分子雲の中のダイヤモンド:星間媒体の標準的なパラダイムへの挑戦
L J Allamandola1, S A Sandford, A G Tielens
1National Aeronautics and Space Administration, Ames Research Center, Mountain View, CA 94035.
Science (New York, N.Y.)
|April 2, 1993
まとめ
密度の高い雲の星間塵は,散らばった雲で見られるCH2およびCH3群とは異なり,独特のダイヤモンドのようなシグネチャーを示しています. この発見は,星間物質の形成と進化の既存のモデルに挑戦しています.
科学分野:
- アストロケミストリー アストロケミストリー
- 恒星間媒体の物理学
- マテリアルサイエンス 材料科学
背景:
- 星間塵の組成は,密集した領域と拡散した領域によって異なる.
- 粉塵の有機分子は,化学的進化において重要な役割を果たします.
- 以前の研究は,密集した星間雲の有機成分を完全に特徴づけることができませんでした.
研究 の 目的:
- 密集した雲の中の星間塵の有機組成を調査する.
- 密度と拡散の星間媒体の有機的シグネチャを比較するために.
- 星間有機物質の形成経路を理解する.
主な方法:
- C-Hストレッチングバンドを検出するための赤外線スペクトロスコーピー.
- 星間塵のスペクトルシグネチャーの分析.
- 密集した星間環境と拡散した星間環境からのデータの比較.
主要な成果:
- 新しい赤外線 C-H ストレッチングバンドが発見され,密集した雲の中でダイヤモンドのような物質の存在を示唆しています.
- 拡散した星間媒体の塵は,−CH2−と−CH3群によって特徴づけられる.
- 密集媒介と拡散媒介の間のアリファティックな有機成分には,重要な二分法が存在します.
結論:
- 密度の高い雲に存在する恒星間ダイヤモンドのような物質の存在は,恒星間過程の標準モデルに挑戦しています.
- この発見は,隕石によるダイヤモンド形成の特定のモデルを排除しています.
- このダイヤモンドのような物質の形成は,一般的な星間プロセスまたは星型に関連している可能性が高い.
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