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arXiv · 1905.02904

Initial results from a systematic search for changing-look active galactic nuclei selected via mid-infrared variability

Zhenfeng Sheng·Tinggui Wang·Ning Jiang·Jiani Ding·Zheng Cai·Hengxiao Guo·Luming Sun·Liming Dou·Chenwei Yang
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Abstract

Changing look active-galatic-nuclei (CL AGNs) can yield considerable insight into accretion physics as well as the co-evolution of black holes and their host galaxies. A large sample of these CL AGNs is essential to achieve the latter goal. We propose an effective method to select CL candidates from spectroscopic quasar catalogs using the mid-infrared (MIR) variability information derived from ALL-WISE/NEOWISE data releases. Our primary selection criteria include both a large amplitude flux variation and a transition of MIR color from an AGN to a normal galaxy. A pilot spectroscopic follow-up of 7 candidates among about 300 candidates selected from Sloan Digital Sky Survey low-redshift (z<0.5) AGN sample results in 6 new turn-off CL AGNs. We expect to obtain hundreds of CL AGNs once full spectroscopic follow-up of the sample is carried out.

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Zhenfeng Sheng, Tinggui Wang, Ning Jiang, Jiani Ding, Zheng Cai, Hengxiao Guo, Luming Sun, Liming Dou, Chenwei Yang. 2019-05-08. Initial results from a systematic search for changing-look active galactic nuclei selected via mid-infrared variability. https://doi.org/10.3847/1538-4357%2Fab5af9

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