Two New "Turn-off" Changing-look Active Galactic nuclei and Implication on "Partially Obscured" AGNs [GA]

http://arxiv.org/abs/1910.02392


We here report a spectroscopic identification of two new changing-look AGNs (CL-AGNs): SDSS\,J104705.16+544405.8 and SDSS\,J120447.91+170256.8 both with a “turn-off” type transition from type 1 to type 1.8/1.9. The identification is arrived by a follow-up spectroscopic observation of the five changing-look AGN (CL-AGN) candidates that are extracted from the sample recently released in Macleod et al. The candidates are extract by the authors from the Sloan Digit Sky Survey Data Release 7 spectroscopically confirmed quasars with large amplitude variability. By compiling a sample of 26 previously identified CL-AGNs, we confirm the claim in Macleod et al. that CL-AGNs tend to be biased against low Eddington ratio, and identify an overlap between the CL-AGNs at their dim state and the so-called intermediate-type AGNs. The overlap implies that there two populations of the intermediate-type AGNs with different origins. One is due to the torus orientation effect, and the another the intrinsic change of the accretion rate of the central supermassive blackholes.

Read this paper on arXiv…

J. Wang, D. Xu, Y. Wang, et. al.
Tue, 8 Oct 19
31/88

Comments: 10 pages, 6 figures and 2 tables, accepted by ApJ