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Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
銀河の中心に向かって爆発する強力な無線源
Scott D Hyman1, T Joseph W Lazio, Namir E Kassim
1Department of Physics and Engineering, Sweet Briar College, Sweet Briar, Virginia 24595, USA. shyman@sbc.edu
Nature
|March 4, 2005
まとめ
天文学者は,銀河の中心近くで,GCRT J1745-3009という新しい一時的なラジオ源を発見しました. そのユニークな爆破特性により,これまで未知だった宇宙トランジントの分類が示唆され,ダイナミックな天体イベントの洞察が提供されています.
科学分野:
- ラジオ天文学 ラジオ天文学
- 天体物理学 天体物理学
- 暫定的な天文現象である.
背景:
- 暫定的な天文学的源は,しばしば爆発的な出来事を意味し,通常はコンパクトな物体によって電力を供給されます.
- ラジオ天文学は高時間解像度の観測を提供しているが,狭い視野によって制限されており,ダイナミックなラジオ空のサンプル採取が不十分である.
- X線およびガンマ線帯域の広場器具は,現在のラジオ天文学の能力とは異なり,一時的な源を定期的に検出します.
研究 の 目的:
- 新型一時的な無線源の検出を報告するには,GCRT J1745-3009.
- この新しい源のバースト特性を特徴付け,既知の無線トランジメンタと比較する.
- 高い明るさの温度とエネルギー密度の影響が放出メカニズムに及ぼす影響を調査する.
主な方法:
- 銀河中心地域の適度な広場モニタリングプログラムを活用しました.
- 0.33GHzの周波数で観測を行った.
- 検出された爆発の時間的特徴とスペクトルの性質を分析した.
主要な成果:
- 銀河中心の領域で,GCRT J1745-3009という一時的な無線源が検出されました.
- 観測されたバストの特徴は,既知のすべてのクラスの無線トランジタとは異なる.
- 約10^16 Kの輝度温度を測定し,一貫した放射と一致する非常に高いエネルギー密度を示しました.
結論:
- GCRT J1745-3009は,これまで知られていなかった,一時的な無線源のクラスを表しています.
- この発見は,新しい広場無線望遠鏡が新しい天文現象を明らかにする可能性を強調しています.
- この発見は,ダイナミックな無線天空は,まだ発見されていない多くのトランジッタ類を宿している可能性があることを示唆している.
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