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arXiv · 2008.11336

Host Galaxy Properties of Changing-look AGN Revealed in the MaNGA Survey

Xiaoling Yu·Yong Shi·Yanmei Chen·Jianhang Chen·Songlin Li·Longji Bing·Junqiang Ge·Rogemar A. Riffel·Rogério Riffel
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Abstract

Changing-look Active Galactic Nuclei (CL-AGNs) are a subset of AGNs in which the broad Balmer emission lines appear or disappear within a few years. We use the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey to identify five CL-AGNs. The 2-D photometric and kinematic maps reveal common features as well as some unusual properties of CL-AGN hosts as compared to the AGN hosts in general. All MaNGA CL-AGNs reside in the star-forming main sequence, similar to MaNGA non-changing-look AGNs (NCL-AGNs). The $80\% \pm 16\%$ of our CL-AGNs do possess pseudo-bulge features, and follow the overall NCL-AGNs $M_{BH}-\sigma_{*}$ relationship. The kinematic measurements indicate that they have similar distributions in the plane of angular momentum versus galaxy ellipticity. MaNGA CL-AGNs however show a higher, but not statistically significant ($20\% \pm 16\%$) fraction of counter-rotating features compared to that ($1.84\% \pm 0.61\%$) in general star-formation population. In addition, MaNGA CL-AGNs favor more face-on (axis ratio $>$ 0.7) than that of Type I NCL-AGNs. These results suggest that host galaxies could play a role in the CL-AGN phenomenon.

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Xiaoling Yu, Yong Shi, Yanmei Chen, Jianhang Chen, Songlin Li, Longji Bing, Junqiang Ge, Rogemar A. Riffel, Rogério Riffel. 2020-08-26. Host Galaxy Properties of Changing-look AGN Revealed in the MaNGA Survey. https://doi.org/10.1093/mnras%2Fstaa2627

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