銀河中心地域の赤外線拡散型星間波帯は,銀河の中心地域にある

T R Geballe¹, F Najarro, D F Figer

¹Gemini Observatory, 670 N. A'ohoku Place, Hilo, Hawaii 96720, USA. tgeballe@gemini.edu

Nature

|November 4, 2011

まとめ

研究者らは,銀河の中心で13の新しい分散星間帯 (DIB) を発見した. これらの宇宙吸収特性は,おそらく炭素ベースの分子であり,以前に観測されたDIBよりも厳しい環境で現れる.

科学分野:

天文学天文学
天体物理学天体物理学
スペクトロスコーピーは,スペクトロスコーピーを用います.

背景:

拡散星間帯 (DIB) は,星間物質による星間スペクトルで観測される吸収特性です.
500以上のDIBが知られているが,主に可視波長と近赤外線波長で発生する.
DIBsの媒体は,多原子炭素を含む分子であると疑われるが,いずれも決定的に特定されていない.

研究の目的:

より長い赤外線波長 (1.5-1.8マイクロメートル) で新しいDIBを探し,特徴づけます.
新しく発見されたDIBの起源と環境を調査する.
銀河中心のDIB特性を他の拡散雲の特性と比較するために.

主な方法:

高解像度スペクトロスコープによる,銀河の中心に向かって,高度に絶滅している恒星の観測.
1.5-1.8マイクロメートルの波長区間のスペクトルの分析.
DIB強度と星間絶滅値の比較.

主要な成果:

1.5-1.8マイクロメートルの範囲で13の新しい分散型恒星間帯を発見した.
これらのDIBは,主に銀河の中心に向かって観測され,この地域からの起源を示唆しています.
これらのDIBの相対的な強さは,以前に知られているDIBに類似して,星間絶滅と相関しています.

結論:

銀河の中心には,これまで知られていなかった星間波帯が広がっており,温暖で厳しい環境から発生しています.
これらの新しいDIBsのキャリアは,既知のDIBsのキャリアに似ており,おそらく多原子炭素分子である可能性があります.
DIBの強さは,特定の環境に関係なく,一般的には拡散した恒星間物質の量に比例します.

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