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Updated: Jul 11, 2026

10:35
Bringing the Visible Universe into Focus with Robo-AO
Published on: February 12, 2013
まとめ
1990年に新しい銀河中心トランジント (GCT) ラジオソースが現れ,1ヶ月後にピークに達した. このトランジタは,おそらくX線バイナリ系からのシンクロトロン放射の結果である.
科学分野:
- ラジオ天文学 ラジオ天文学
- 銀河中心の研究は,銀河中心研究である.
- 暫定的な天文現象である.
背景:
- 新しい無線源である銀河中心トランジエント (GCT) は,1990年後半に銀河の中心近くで発生した.
- GCTの強度は,銀河の中心にある既設のコンパクト無線源である Sagittarius A* (Sgr A*) の強さと同等だった.
研究 の 目的:
- 新しく発見された銀河中心トランジント (GCT) の特徴と起源を分析する.
- ラジオ吸収と赤外線観測を用いてGCTの位置と性質を決定する.
主な方法:
- GCTのフクス密度とラジオスペクトルを時間とともにモニタリングする.
- 中性水素 (HI) とヒドロキシル (OH) の吸収線スペクトロスコーピーを利用する.
- 既知の銀河中心の情報源とGCT吸収特性を比較する.
- 地域の赤外線画像を分析する.
主要な成果:
- GCTはフクロス密度の急速な増加を示し,1ヶ月以内にピークに達し,その後3ヶ月間にわたって徐々に減少しました.
- GCTの上昇段階と衰退段階の両方で,急なラジオスペクトルが一貫して観察されました.
- HI吸収は,Sgr A*に似たように,GCTが銀河の中心に近づいていることを示した.
- HIとOHの観測は,+20 km/sの分子雲に一致する吸収を明らかにし,GCTがこの雲に埋め込まれているか,またはその背後にあることを示唆しています.
- 赤外線観測により,この分子雲の存在が確認されましたが,その不透明性は近くの超新星を遮るには不十分でした.
結論:
- GCTは,局所的な静止基準に対して+20 km/sで移動する分子雲の近く,またはその中に位置しています.
- GCTの観測された性質は,超新星と矛盾しています.
- GCTの最も可能性の高い説明は,X線バイナリ系内のシンクロトロン放射から発生する一時的な無線放射である.
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