超光X線源M 101 ULX-1のブラックホールに謎の蓄積がある
Ji-Feng Liu1, Joel N Bregman, Yu Bai
1Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, 20A Datun Road, Chaoyang District, 100012 Beijing, China.
Nature
|November 29, 2013
まとめ
超光るX線源 (ULXs) は,中等質量ブラックホールまたは恒星質量ブラックホールによって説明されます. M101 ULX-1の新しい観測は,恒星風からの増殖がこれらの極端な宇宙物体を動かすことを示唆しています.
科学分野:
- 天体物理学 天体物理学
- X線天文学 X線天文学
- ブラックホールの研究
背景:
- 超光るX線源 (ULXs) は,中間質量ブラックホール (IMBHs) または超エディントン速度で増加する恒星質量ブラックホール (SBHs) の2つの主要な形成仮説を提示しています.
- 注目すべきULXであるM101 ULX-1は,その高い明るさと柔らかい熱ディスクスペクトルにより,当初はIMBHと一致する特徴を示していた.
研究 の 目的:
- M101 ULX-1の性質を調査し,ULX形成理論における二分論を解決する.
- M101 ULX-1のブラックホールの質量と蓄積メカニズムを決定する.
主な方法:
- M101 ULX-1の光学スペクトルモニタリング
- 軌道周期とブラックホールの質量推定の分析.
- 増積過程を理解するためのスペクトル分析.
主要な成果:
- M101 ULX-1系におけるウルフ・ライエットの伴星が確認されました.
- 8.2日間の軌道周期を決定した.
- ブラックホールの質量は太陽の質量20~30倍と推定されており,IMBHの分類を強く否定している.
- 高いエディントン比で例外的に柔らかいスペクトルを観測し,標準的なSBH増殖モデルと矛盾しています.
結論:
- M101 ULX-1は中等質量ブラックホールである可能性は低い.
- M101 ULX-1の高い明るさは,捕獲された恒星風からの蓄積によって提供され,蓄積効率に関する以前の仮定に異議を唱えます.
関連する概念動画
Detection of Black Holes
2.6K
Although black holes were theoretically postulated in the 1920s, they remained outside the domain of observational astronomy until the 1970s.
Their closest cousins are neutron stars, which are composed almost entirely of neutrons packed against each other, making them extremely dense. A neutron star has the same mass as the Sun but its diameter is only a few kilometers. Therefore, the escape velocity from their surface is close to the speed of light.
Not until the 1960s, when the first neutron...
Their closest cousins are neutron stars, which are composed almost entirely of neutrons packed against each other, making them extremely dense. A neutron star has the same mass as the Sun but its diameter is only a few kilometers. Therefore, the escape velocity from their surface is close to the speed of light.
Not until the 1960s, when the first neutron...
2.6K
Schwarzschild Radius and Event Horizon
3.0K
No object with a finite mass can travel faster than the speed of light in a vacuum. This fact has an interesting consequence in the domain of extremely high gravitational fields.
The minimum speed required to launch a projectile from the surface of an object to which it is gravitationally bound so that it eventually escapes the object’s gravitational field is called the escape velocity. The escape velocity is independent of the mass of the object. Merging the idea of escape...
The minimum speed required to launch a projectile from the surface of an object to which it is gravitationally bound so that it eventually escapes the object’s gravitational field is called the escape velocity. The escape velocity is independent of the mass of the object. Merging the idea of escape...
3.0K
X-ray Imaging
11.1K
German physicist Wilhelm Röntgen (1845–1923) was experimenting with electrical current when he discovered that a mysterious and invisible "ray" would pass through his flesh but leave an outline of his bones on a screen coated with a metal compound. In 1895, Röntgen made the first durable record of the internal parts of a living human: an "X-ray" image (as it came to be called) of his wife’s hand. Scientists worldwide quickly began their own experiments with...
11.1K
Absorption of Radiation
1.6K
The rate of heat transfer by emitted radiation is described by the Stefan-Boltzmann law of radiation:
1.6K
Gravitation Between Spherically Symmetric Masses
1.5K
The gravitational potential energy between two spherically symmetric bodies can be calculated from the masses and the distance between the bodies, assuming that the center of mass is concentrated at the respective centers of the bodies.
1.5K
Momentum And Radiation Pressure
2.6K
An object absorbing an electromagnetic wave would experience a force in the direction of propagation of the wave. This force occurs because electromagnetic waves contain and transport momentum. The force accounts for the wave's radiation pressure exerted on the object. Maxwell's prediction was confirmed in 1903 by Nichols and Hull by precisely measuring radiation pressures with a torsion balance. The measuring instrument had mirrors suspended from a fiber kept inside a glass container.
2.6K


