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تسجيل مستخدم جديدTwo New Turn-off Changing-look Active Galactic nuclei and Implication on Partially Obscured AGNs
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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.
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