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arXiv · 1011.2802

The orientation of the nuclear obscurer of the AGNs

Shiyin Shen·Zhengyi Shao·Minfeng Gu
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Abstract

We examine the distribution of axis ratios of a large sample of disk galaxies hosting type 2 AGNs selected from the Sloan Digital Sky Survey and compare it with a well-defined control sample of non-active galaxies. We find them significantly different, where the type 2 AGNs show both an excess of edge-on objects and deficit of round objects. This systematical bias can not be explained by a nuclear obscurer oriented randomly with respect to the stellar disk. However, a nuclear obscurer coplanar with the stellar disk also does not fit the data very well. By assuming that the nuclear obscurer having an opening angle of ~60 degree, we find the observed axis ratio distribution can be nicely reproduced by a mean tilt angle of ~30 degree between the nuclear obscurer and the stellar disk.

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Shiyin Shen, Zhengyi Shao, Minfeng Gu. 2010-11-12. The orientation of the nuclear obscurer of the AGNs. https://doi.org/10.1088/2041-8205%2F725%2F2%2Fl210

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