GEMSと星間粒子の間の赤外線スペクトルマッチ
J P Bradley1, L P Keller, T P Snow
1MVA Inc., Norcross, GA 30093, USA.
Science (New York, N.Y.)
|September 11, 1999
まとめ
惑星間塵粒子 (IDP) の赤外線スペクトルは,天文学的シリケートと一致する. いくつかのIDPは,太陽系彗星や若い恒星に似ているが,他のものは星間塵を鏡に映し,太陽系形成とのつながりを示唆している.
科学分野:
- 宇宙の塵と惑星の形成
- 赤外線スペクトロスコーピーは,赤外線スペクトロスコーピーを用います.
- アストロケミストリー アストロケミストリー
背景:
- 惑星間塵粒 (IDP) は,太陽系初期からの残骸である.
- 天文学的シリケートは,星と惑星の形成モデルにおける重要な構成要素である.
- シリケートの性質を理解することは,材料の起源を追跡するために非常に重要です.
研究 の 目的:
- IDPのシリケート粒子の赤外線スペクトル特性を天文学的シリケートと比較する.
- 太陽系内外の塵の起源と進化を調査する.
- IDPと様々な天文塵の集団のスペクトルの類似性を特定する.
主な方法:
- 赤外線スペクトロスコピーは,IDPのシリコン-酸素のストレッチバンドを分析するために使用されました.
- IDPのスペクトル特性 (細かい構造,帯域幅) と,既知の天文学的シリケートスペクトルとの比較.
- エンスタチット,フォーステライト,および金属と硫化物 (GEMS) が埋め込まれたガラスを含むIDPの分析.
主要な成果:
- エンスタチット,フォーステライト,およびいくつかのGEMSを含むIDPは,彗星やHerbig Ae/Be星に似たスペクトル特徴を示した.
- 特定のGEMSは,星間分子雲と若い恒星物体のスペクトルに一致する,広い,特徴のないシリコン-酸素帯を展示しました.
- これらのGEMSは,天文学的"無形"シリケートにスペクトルマッチを提供する.
結論:
- IDPは様々な赤外線スペクトル特性を示し,異なる形成と処理経緯を反映しています.
- いくつかのIDPは,星間物質から発生し,共通の塵のプールという考えを支持する可能性があります.
- GEMSとアモルフォスシリケートのスペクトルの類似性は,太陽系の構成要素としての役割を支持しています.
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