パルサーによって刺激されたパルス型OHマザー放射の発見
Joel M Weisberg1, Simon Johnston, Bärbel Koribalski
1Australia Telescope National Facility/Commonwealth Scientific and Industrial Research Organisation, Post Office Box 76, Epping, NSW 1710, Australia. jweisber@carleton.edu
Science (New York, N.Y.)
|May 28, 2005
まとめ
天文学者は,パルサーB1641-45.5によって誘発された恒星間ヒドロキシル (OH) 雲からの刺激された放射の放射を観測しました. この発見は急速な変化を明らかにし,星間ガス雲の構造についての洞察を提供します.
科学分野:
- 天体物理学 天体物理学
- ラジオ天文学 ラジオ天文学
- 星間媒介は,星間媒介である.
背景:
- 刺激された放射線の放出は,天体物理的な環境では直接観察されていません.
- 星間ヒドロキシル (OH) マザーに関する以前の観測は,より遅い変動を示した.
研究 の 目的:
- 天体物理学的な文脈で刺激された放射線の放射を直接観察する.
- 星間ヒドロキシル (OH) 雲の性質とパルサーとの相互作用を調査する.
主な方法:
- 恒星間ヒドロキシル (OH) 雲からの1720メガヘルツ以上の線放射の観測.
- 1612メガヘルツのスペクトルと1720メガヘルツのスペクトルの組み合わせの分析.
- パルサー信号の吸収を他の背景からの吸収と比較.
主要な成果:
- パルサーB1641-45からの光子によって誘発された恒星間OH雲からの刺激された放射の直接観測.
- パルサーの信号に関連した,刺激された放射の急速な (ミリ秒の時間スケール) 変動の検出.
- 1612メガヘルツのスペクトルが1720メガヘルツのスペクトルの逆転したコピーである"結合線"現象の識別.
- OH雲は中性水素雲よりも小規模な塊状性が大きいことを確認し,パルサー信号の吸収がより深く示されています.
結論:
- この研究は,天体物理環境における刺激された放射の放射の直接的証拠を初めて提供している.
- "結合線"現象は,星間OHガスの性質を制限するための新しい方法を提供します.
- パルサーの観測は,星間OH雲の塊状の性質を小規模で確認しています.
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