天文学进展2017，Vol.35Issue(1)：54-92,39.DOI:10.3969/j.issn.1000-8349.2017.01.04
高红移低光度活动星系核的研究进展
Studies of High-Redshift Low-Luminosity AGNs
摘要
Abstract
The studies of Active Galactic Nuclei (AGNs) at high redshifts (z ≈ 3) have been mostly limited to color selected quasars (QSOs).QSOs are bright and have point-like morphologies,making them easy to be selected in imaging surveys.However,QSOs are the minorities in the full AGN population,as is well studied in the luminosity function of AGNs.The majority of the AGN population-the low-luminosity AGNs (hereafter LLAGNs)-remains largely inaccessible.Throughout this paper,we refer to AGNs that are at least one or two magnitudes fainter than the SDSS-Ⅲ/BOSS QSOs as LLAGNs.Particularly,the surveys with LLAGNs should be 23 ～ 24 AB mag deep in g-band (-24 ～ Mg[z =3] mag-1 (≦)-23) or deeper (the limiting magnitude for the SDSS-Ⅲ/BOSS survey is r ＜ 21.85 mag or g ＜ 22 mag)[10].LLAGNs are important,for example,for the purpose of constraining the faint end of the luminosity function of AGNs,studying the differences in the fueling mechanisms between weak and strong AGNs,and exploring the potential relationship between supermassive black holes and the large-scale structure in which their host galaxies reside.The sky coverages and the sample sizes of current deep surveys that contain LLAGNs at z ≈ 3 are limited ((≦) 2 deg2,(≈) 102).In this paper,we present both photometric and spectroscopic surveys that include LLAGN samples at z (≈) 3.We also introduce the HETDEX survey,which will be online in 2017 and will observe more than 104 low-luminosity type 1 AGNs at 2 ＜ z ＜ 4.We summarize these surveys according to their luminosity functions,clustering,and Eddington ratios.To better show the power of studies on the clustering of AGNs,we include the results of the clustering of LLAGNs at low redshifts,in addition to those at high redshifts,that are based on relatively limited samples.关键词
高红移星系/低光度活动星系核/星系演化/宇宙大尺度结构Key words
high-redshift galaxies/Low-Luminosity AGN/galaxies evolution/large-scale structure of universe分类
天文与地球科学引用本文复制引用
刘辰旭,郝蕾..高红移低光度活动星系核的研究进展[J].天文学进展,2017,35(1):54-92,39.基金项目
国家自然科学基金(11473305) （11473305）
