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Title: The Physical Properties of Low-redshift FeLoBAL Quasars. II. The Rest-frame Optical Emission Line Properties
Abstract We report the results of an analysis of the H β emission line region of a sample of 30 low-redshift ( z < 1) iron low-ionization broad absorption line quasars (FeLoBALQs). Eleven of these objects are newly classified as FeLoBALQs. A matched sample of 132 unabsorbed quasars was analyzed in parallel. The emission lines showed the well-known anticorrelation between the [O iii ] and Fe ii emission. Using a summary statistic called E 1 to quantify this anticorrelation, we found that while the distribution of E 1 for the unabsorbed quasars has a single peak, the FeLoBALQs have a bimodal shape in this parameter. Previous studies have shown that the line emission properties of BAL and non-BALQs are consistent; therefore, the difference in the H β region emission between FeLoBALQs and unabsorbed quasars is a new result. The two populations of FeLoBALQs are characterized by low and high bolometric luminosities and Eddington ratios. Some previous studies have suggested that BALQs are high accretion rate objects and therefore the discovery of the low accretion rate branch of FeLoBAL quasars was unexpected. We also found that the H β FWHM is systematically broader among the FeLoBALQs, implying a higher inclination viewing angle or a dearth of low velocity line emitting gas.  more » « less
Award ID(s):
2006771 1518382 2007023
PAR ID:
10432990
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
935
Issue:
2
ISSN:
0004-637X
Page Range / eLocation ID:
92
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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