4,430アングストロムの星間吸収帯の原因はピレンのような分子イオンでしょうか?
1NASA-Ames Research Center, Space Science Division, Moffett Field, California 94035, USA.
Nature
|July 2, 1992
まとめ
拡散星間帯 (DIB) は,天文学的吸収特征である. 実験室での測定は,ピレンカチオンが特定のDIBの原因である可能性を示唆し,ポリサイクル芳香炭化水素が星間光をどのように処理するかを説明する可能性がある.
科学分野:
- 天文学と天体物理学について
- アストロケミストリー アストロケミストリー
- スペクトル顕微鏡検査です.
背景:
- 拡散星間帯 (DIB) は,天文スペクトルの多くの吸収特征である.
- DIBの媒介体は未だに特定されていないが,ガス型か穀物型かについては議論が続いている.
- ポリサイクル芳香炭化水素 (PAH) は,いくつかのDIBキャリアの分子候補である.
研究 の 目的:
- 実験室のマトリックスでピレンカチオン (C16H10+) の光学スペクトルを調査する.
- 実験室で測定したスペクトルとDIBの天文観測を比較する.
- 星間光の処理におけるPAHカチオンの潜在的な役割を調査する.
主な方法:
- ネオンとアルゴン行列を用いたピレンカチオン (C16H10+) の光学スペクトルの実験室測定.
- ピーク位置と連続体特性を含む吸収特性の分析.
- 既知の天文DIBとスペクトルデータの比較.
主要な成果:
- ピレンカチオンは4,430アングストーム近くの強い吸収特性を示し,顕著なDIB.と整列しています.
- この特定のDIBは,ピレンのような種に属している場合,宇宙の炭素の0.2%を必要とします.
- 紫外線から可視波長までの強烈で幅広い連続は,ナフタレンカチオンに似たピレンカチオンに観察されました.
結論:
- ピレンカチオンは,4,430アングストロムのDIB.の妥当な候補である.
- PAHカチオンは,UV/可視星間放射線を赤外線に変換する共通の連続体特性を有している可能性があります.
- この研究は,星間物質の組成とエネルギー転送プロセスの理解に貢献します.
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