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The effect of bars on the obscuration of active nuclei

R. Maiolino·G. Risaliti·M. Salvati
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Abstract

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 Sy2s. More than 80% of Compton thick (Nh>10^24 cm^-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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R. Maiolino, G. Risaliti, M. Salvati. 1998-11-15. The effect of bars on the obscuration of active nuclei. https://arxiv.org/abs/astro-ph/9811237

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