The effect of bars on the obscuration of active nuclei
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چکیده
We present evidence for a strong correlation between the gaseous absorbing column density towards type 2 Seyfert nuclei and the presence of a stellar bar in their host galaxies. Strongly barred Seyfert 2 galaxies have an average NH that is two orders of magnitude higher than non-barred Seyfert 2s. More than 80% of Compton thick (NH > 1024cm−2) Seyfert 2s are barred. This result indicates that stellar bars are effective in driving gas in the vicinity of active nuclei.
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تاریخ انتشار 1998