What broad emission lines tell us about how active galactic nuclei work
نویسندگان
چکیده
منابع مشابه
4 A ug 2 00 9 What broad emission lines tell us about how active galactic nuclei work
I review progress made in understanding the nature of the broad-line region (BLR) of active galactic nuclei (AGNs) and the role BLRs play in the AGN phenomenon. The high equivalent widths of the lines imply a high BLR covering factor, and the absence of clear evidence for absorption by the BLR means that the BLR has a flattened distribution and that we always view it near pole-on. The BLR gas i...
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Using an empirical relation between the broad line region size and optical continuum luminosity, we estimated the black hole mass and accretion rate for 135 AGNs with double-peaked broad emission lines in two samples, one from the SDSS and the other from a survey of radio-loud broad emission line AGNs. With black hole masses in a range from 3×10M⊙ to 5×10 M⊙, these AGNs have the dimensionless a...
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Aims. Type II AGNs with polarimetric broad emission line provided strong evidence for the orientation-based unified model for AGNs. We want to investigate whether the polarimetric broad emission line in type II AGNs can be used to calculate their central supermassive black hole (SMBH) masses, like that for type I AGNs. Methods. We collected 12 type II AGNs with polarimetric broad emission line ...
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ژورنال
عنوان ژورنال: New Astronomy Reviews
سال: 2009
ISSN: 1387-6473
DOI: 10.1016/j.newar.2009.09.006