论文标题
从ASAS-SN调查中选择的可变性活性银河核：限制低光度AGN种群
Variability Selected Active Galactic Nuclei from ASAS-SN Survey: Constraining the Low Luminosity AGN Population
论文作者
论文摘要
低亮度活跃的银河核（LLAGN）探针积物物理学，在低爱丁顿制度中，可以提供有关星系进化的其他线索。 AGN的可变性无处不在，因此为查找AGN提供了可靠的工具。我们分析了1218个星系的超新星光曲线的全高自动化调查，其中$ g <14 $ mag和斯隆数字天空调查光谱，以寻找AGN。我们发现37个既有变量又具有类似AGN的结构函数的对象，约占样品的3％。所选AGN的大多数可变性为llagn，爱丁顿比率从$ 10^{ - 4} $到$ 10^{ - 2} $不等。因此，我们估计星系人群中LLAGN的分数为2％，降至中位数埃丁顿的比例为$ 2 \ times10^{ - 3} $。将BPT线比的诊断和广泛的AGN结合在一起，可通过光谱镜进行确认。 BPT诊断还将10-30％的候选者归类为星系星系，而不是AGN。
Low luminosity active galactic nuclei (LLAGN) probe accretion physics in the low Eddington regime and can provide additional clues about galaxy evolution. AGN variability is ubiquitous and thus provides a reliable tool for finding AGN. We analyze the All-Sky Automated Survey for SuperNovae light curves of 1218 galaxies with $g<14$ mag and Sloan Digital Sky Survey spectra in search of AGN. We find 37 objects that are both variable and have AGN-like structure functions, which is about 3% of the sample. The majority of the variability selected AGN are LLAGN with Eddington ratios ranging from $10^{-4}$ to $10^{-2}$. We thus estimate the fraction of LLAGN in the population of galaxies as 2% down to a median Eddington ratio of $2\times10^{-3}$. Combining the BPT line ratio diagnostics and the broad-line AGN, up to $\sim$60% of the AGN candidates are confirmed spectroscopically. The BPT diagnostics also classified 10-30% of the candidates as star forming galaxies rather than AGN.
