AGN with faint broad line regions: Some `True'-Seyfert 2s might be Narrow Line Seyfert 1s
Abstract
The intriguing existence of `True'-Seyfert 2s has opened a debate on the validity of the unified model of active galactic nuclei (AGN). These objects, also called `Naked'-AGN, seem to lack a broad line region. In some cases, their X-ray emission is unabsorbed, typical of Seyfert 1 galaxies, indicating a clear view toward the nucleus, but no broad lines are seen in the optical. In `True'-Seyfert 2s with higher column densities, observations of polarized light have failed to reveal the hidden broad emission. We performed high-resolution near-infrared integral-field observations of two `True'-Seyfert 2 candidates: IRAS 01072+4954 and NGC 7496. We found that the AGN in these sources might power very faint and narrow broad emission lines (FWHMbroad < 1500km s-1). Here, we discuss the properties of the broad components estimated from published X-ray and/or optical measurements and present their near-infrared candidate identification. Both galaxies host intermediate-mass black holes, with masses ~ 105-106 M⊙. Our results favor the unified model in the cases of high accretion rates, and stress the necessity of a multiwavelength approach to unveil the nature of `Naked'-AGN.
- Publication:
-
Multiwavelength AGN Surveys and Studies
- Pub Date:
- July 2014
- DOI:
- 10.1017/S1743921314004050
- Bibcode:
- 2014IAUS..304..274V
- Keywords:
-
- galaxies: Seyfert;
- galaxies: fundamental parameters;
- techniques: high angular resolution;
- line: profiles;
- galaxies: individual (IRAS 01072+4954;
- NGC 7496)