Astronomy and Astrophysics – Astrophysics – Cosmology and Extragalactic Astrophysics
Scientific paper
2010-08-30
Please refer to Research in Astronomy and Astrophysics, 2010, Volume 10, Issue 5, pp. 427-437
Astronomy and Astrophysics
Astrophysics
Cosmology and Extragalactic Astrophysics
Scientific paper
From the literature, we construct from literature a sample of 25 Seyfert 2 galaxies (S2s) with a broad line region detected in near infrared spectroscopy and 29 with NIR BLR which was detected. We find no significant difference between the nuclei luminosity (extinction-corrected [OIII]~5007) and infrared color $\rm{f_{60}/f_{25}}$ between the two populations, suggesting that the non-detections of NIR BLR could not be due to low AGN luminosity or contamination from the host galaxy. As expected, we find significantly lower X-ray obscurations in Seyfert 2s with NIR BLR detection, supporting the unification scheme. However, such a scheme was challenged by the detection of NIR BLR in heavily X-ray obscured sources, especially in six of them with Compton-thick X-ray obscuration. The discrepancy could be solved by the clumpy torus model and we propose a toy model demonstrating that IR-thin X-ray-thick S2s could be viewed at intermediate inclinations, and compared with those IR-thick X-ray-thick S2s. We note that two of the IR-thin X-ray-thick S2s (NGC 1386 and NGC 7674) experienced X-ray transitions, i.e. from Compton-thin to Compton-thick appearance or vice versa based on previous X-ray observations, suggesting that X-ray transitions could be common in this special class of objects.
Cai Hong-bing
Shu Xin Wen
Wang Jun-Xian
Zheng Zhen-Ya
No associations
LandOfFree
The study of Seyfert 2 galaxies with and without infrared broad lines does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The study of Seyfert 2 galaxies with and without infrared broad lines, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The study of Seyfert 2 galaxies with and without infrared broad lines will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-400714