论文标题
可能：巨型射电星系比我们想象的更普遍？
MIGHTEE: Are giant radio galaxies more common than we thought?
论文作者
论文摘要
我们报告了使用Meerkat International GHz分层外层次探索（Mightee）调查发现了两个新的巨型射电星系（GRG）。在宇宙场内的一个1 deg^2区域中发现了两个GRG。它们的红移为Z = 0.1656，Z = 0.3363，物理大小分别为2.4MPC和2.0MPC。在先前的高分辨率VLA观测中，仅这些GRG的核心才能清楚地看到，因为裂片的弥漫性发射已解决。但是，新的Meerkat望远镜的出色灵敏度和紫外线覆盖范围可以检测到这种弥漫性发射。 GRG占据了无线电功率 - 大小参数空间的无人命的区域。基于对GRG数量密度的最新估计，在〜1Deg^2场中找到两个或多个grg的概率仅为2.7x10^-6，假定Poisson统计量为2.7x10^-6。这支持了以下假设：由于对低表面亮度发射的敏感性有限，过去GRG的患病率已被显着低估。此处介绍的两个GRG可能是通过Mightee等调查揭示的新人群中的第一个，该调查对扩散，扩展排放提供了精致的敏感性。
We report the discovery of two new giant radio galaxies (GRGs) using the MeerKAT International GHz Tiered Extragalactic Exploration (MIGHTEE) survey. Both GRGs were found within a 1 deg^2 region inside the COSMOS field. They have redshifts of z=0.1656 and z=0.3363 and physical sizes of 2.4Mpc and 2.0Mpc, respectively. Only the cores of these GRGs were clearly visible in previous high resolution VLA observations, since the diffuse emission of the lobes was resolved out. However, the excellent sensitivity and uv coverage of the new MeerKAT telescope allowed this diffuse emission to be detected. The GRGs occupy a unpopulated region of radio power - size parameter space. Based on a recent estimate of the GRG number density, the probability of finding two or more GRGs with such large sizes at z<0.4 in a ~1deg^2 field is only 2.7x10^-6, assuming Poisson statistics. This supports the hypothesis that the prevalence of GRGs has been significantly underestimated in the past due to limited sensitivity to low surface brightness emission. The two GRGs presented here may be the first of a new population to be revealed through surveys like MIGHTEE which provide exquisite sensitivity to diffuse, extended emission.
