镜头类类星体中强重力模式的反射在红移z = 0.658的红移z = 0.658的反射
R C Reis1, M T Reynolds1, J M Miller1
1Department of Astronomy, University of Michigan, Ann Arbor, Michigan 48109, USA.
Nature
|March 7, 2014
概括
超大质量黑洞在适度的红移时成长得连贯,而不是混乱. 这项研究使用相对论反射测量了z=0.658的高黑洞旋转,表明持续的积累增长.
科学领域:
- 天体物理学和宇宙学
- 黑洞物理学 黑洞物理学
- 银河系的进化 银河系的进化
背景情况:
- 超大质量黑洞 (SMBH) 旋转是它们与宿主星系共同进化的关键指标.
- 据认为,中小企业在高红色偏移 (z > 2) 的情况下通过合并驱动的增量增长,从而导致高旋转.
- 在中度红移 (z < 1) 时,SMBHs的积累模式 (连贯与混乱) 仍然不太清楚.
研究的目的:
- 通过测量其旋转来调查中度红移的SMBH的积累历史.
- 为了确定z ~ 0.5-1时的SMBH是否主要通过连贯或混乱的增殖生长.
主要方法:
- 对档案X射线数据的分析与对z = 0.658.8的重力透镜类星体的深度观测相结合.
- 通过研究来自内部积累盘的相对论反射特征来测量SMBH旋转.
- 使用引力透镜来克服探测微弱反射信号的距离限制.
主要成果:
- 检测来自黑洞三个引力半径内的相对论反射特征.
- 确定一个高黑洞旋转参数,a = 0.87(+0.08)(-0.15) 在3σ置信度,和a>0.66在5σ.
- 测量的高旋转强烈表明通过连贯的积累情节增长.
结论:
- 透镜类星体中的SMBH表现出高旋转,与通过连贯增长的增长相一致.
- 这一发现表明,在中度红移 (0.5 ≤ z ≤ 1) 的情况下,SMBH的增长主要是由连贯的增长驱动的.
- 该研究提供了第一个显著的检测相对论反射在一个中等红移类星,使旋转测量.
相关概念视频
01:21Schwarzschild Radius and Event Horizon
2.2K
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...
2.2K
01:10Detection of Black Holes
1.7K
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...
1.7K
01:16Focusing of Light in the Eye
6.2K
Light rays enter the eye through the cornea, a transparent dome-shaped tissue that is the eye's outermost layer. The cornea bends or refracts, light rays traveling to the pupil. The shape of the cornea determines how much of the light is bent and whether the image will be focused correctly on the retina at the back of the eye. Once the light has passed through both refraction layers, it converges into a single focal point onto a small area. This is where photoreceptors start transforming...
6.2K
01:05Total Internal Reflection Fluorescence Microscopy
11.0K
Total internal reflection fluorescence microscopy or TIRF is an advanced microscopic technique used to visualize fluorophores in samples close to a solid surface with a higher refractive index, such as a glass coverslip. TIRF only allows fluorophores in proximity to the solid surface to be excited. When light from a medium with a lower refractive index (such as air) hits the glass coverslip at a critical angle, the light undergoes total internal reflection stead of passing through the glass.
11.0K
01:37Super-resolution Fluorescence Microscopy
12.3K
Super-resolution fluorescence microscopy (SRFM) provides a better resolution than conventional fluorescence microscopy by reducing the point spread function (PSF). PSF is the light intensity distribution from a point that causes it to appear blurred. Due to PSF, each fluorescing point appears bigger than its actual size, and it is the PSF interference of nearby fluorophores that causes the blurred image. Various approaches to achieving higher resolution through SRFM have recently been...
12.3K
01:07Reflection of Waves
3.7K
When a wave travels from one medium to another, it gets reflected at the boundary of the second medium. A common example of this is when a person yells at a distance from a cliff and hears the echo of their voice. The sound waves (longitudinal waves) traveling in the air are reflected from the bounding cliff. Similarly, flipping one end of a string whose other end is tied to a wall causes a pulse (transverse wave) to travel through the string, which gets reflected upon reaching the wall. In...
3.7K