一个重复的快速无线电爆发源定位在附近的螺旋星系
B Marcote1, K Nimmo2,3, J W T Hessels4,5
1Joint Institute for VLBI ERIC (JIVE), Dwingeloo, The Netherlands.
Nature
|January 8, 2020
概括
第二次重复的快速无线电爆发 (FRB) 正确地定位到一个巨大的螺旋星系. 这一发现表明重复的FRB来自不同的环境, 挑战了关于它们起源的先前假设.
科学领域:
- 天文学与天体物理学
- 宇宙现象
背景情况:
- 快速无线电爆发 (FRB) 是一个神秘的,强大的银河系外无线电信号,
- 虽然已经发现了100多个FRB源,但只有少数被精确地定位为宿主星系.
- 第一个局部重复的FRB (FRB 121102) 在一个矮星系中被发现,与大质量星系中不重复的FRB形成鲜明对比.
研究的目的:
- 准确地定位第二个重复的快速无线电爆发 (FRB) 源.
- 调查这个新的反复FRB源的宿主星系和本地环境.
- 将该源的特性与之前局部化的重复FRB (FRB 121102) 和非重复FRB进行比较.
主要方法:
- 对FRB 180916 J0158+65反复发射源进行精确的无线电干扰测定.
- 天文观测以描述宿主星系的属性 (例如红移,形态,恒星形成活动).
- 分析当地环境,包括寻找持久无线电对应物和测量法拉第旋转.
主要成果:
- FRB 180916.J0158+65被精确地定位在一个附近的大型螺旋星系中的恒星形成区域 (z = 0.0337 ± 0.0002).
- 主星系及其附近与已知的FRB主星系有很大的不同.
- 当地环境缺乏明亮的持续无线电对应物,并表现出低法拉第旋转量,与FRB 121102不同.
结论:
- 重复的FRB可以来自不同的宿主星系和本地环境,而不仅仅是矮星系.
- 这些发现表明重复FRB的发光度和起源范围比以前推断的更广.
- 这一发现需要对FRB原始体及其进化途径进行修订.
相关概念视频
Detection of Black Holes
2.5K
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...
2.5K
IR Frequency Region: X–H Stretching
1.3K
In IR spectroscopy, signals produced by the X−H bonds (such as C−H, O−H, or N−H) can be observed in the frequency range of 2700–4000 cm–1. The C−H stretching vibration forms sharp bands in the region 2850–3000 cm–1. The presence of the O−H stretching vibration leads to the forming of an absorption band in the frequency range 3650–3200 cm−1. At the same time, N−H stretching can be confirmed by absorption bands in...
1.3K
Super-resolution Fluorescence Microscopy
12.1K
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...
12.1K
Schwarzschild Radius and Event Horizon
2.6K
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...
2.6K
Atomic Nuclei: Larmor Precession Frequency
2.6K
The earth's gravitational field produces a 'twisting force' perpendicular to the angular momentum of a spinning mass (such as a spinning top) that causes the mass to 'wobble' around the gravitational field axis in a phenomenon called precession. Similarly, the magnetic moment (μ) of a spinning nucleus precesses due to an external magnetic field directed along the z-axis. The precession of the magnetic moment vector about the magnetic field is called Larmor precession,...
2.6K
Gravitation Between Spherically Symmetric Masses
1.2K
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.
1.2K


