NGC 1068の活発な核の中央の塵に満ちたトーラス
W Jaffe1, K Meisenheimer, H J A Röttgering
1Leiden Observatory, Niels Bohrweg 2, 2333 CA Leiden, The Netherlands. jaffe@strw.leidenuniv.nl
Nature
|May 7, 2004
まとめ
インターフェロメトリックの中赤外線観測により,活性銀河核 (AGN) の塵の渦が初めて空間的に解明されました. この構造は,AGNの外観を理解するために不可欠であり,安定性を保つために継続的なエネルギー投入を必要とします.
科学分野:
- 天文学 天文学
- 天体物理学 天体物理学
- 銀河の進化 銀河の進化 銀河の進化
背景:
- 活発な銀河核 (AGN) は,超大質量ブラックホールに物質の蓄積が起因するエネルギー現象を示しています.
- AGNの観測外観は,中心部地域を遮る環核塵による方向効果の影響を受けていると広く信じられています.
- 以前の間接的な証拠は,これらの塵雲のパーセックサイズの,トーラス状の分布を示唆していたが,直接的な解像度は難しかった.
研究 の 目的:
- 活発な銀河核の中央エンジンを取り囲むパーセックサイズの塵の構造を空間的に解明するために.
- AGNにおける提案されたトーラスモデルに対する直接的な観察的証拠を提供すること.
- 解けた塵構造の物理的条件と安定性を調査する.
主な方法:
- インターフェロメトリックの中赤外線観測を用いた.
- 高解像度画像を撮るために,銀河NGC 1068を標的にしました.
- 塵の構造の空間的分布と温度を分析した.
主要な成果:
- 空間的に解明された熱い (320 K) 塵は,NGC 1068のより熱い中心部周辺のトーラス状の構造 (厚さ 2.1 pc,直径 3.4 pc) にあります.
- AGNにおける環原子塵構造の直接的な,解像度の高い画像を初めて提供した.
- 観測された塵の構成は,短い時間スケールで動的に不安定である.
結論:
- NGC 1068の塵の渦の直接的な解像度は,AGN観測の形成におけるその役割を確認しています.
- 観測された塵構造の不安定性は,AGNと共存する継続的なエネルギー入力メカニズムを暗示しています.
- この運動エネルギー投入の源と,AGNの進化に与える影響を特定するために,さらなる研究が必要です.
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