The Physical Properties of Low-Redshift FeLoBAL Quasars: II. The Rest-Frame Optical Emission Line Properties

Abstract

We report the results of analysis of the Hbeta emission-line region of a sample of thirty 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 [OIII] and FeII emission (Boroson & Green 1992). Using a summary statistic called E1 to quantify this anticorrelation, we found that while the distribution of E1 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-BAL quasars are consistent, and therefore the difference in the Hbeta region emission between FeLoBAL quasars and unabsorbed quasars is a new result. The two populations of FeLoBAL quasars are characterized by low and high bolometric luminosities and Eddington ratios. Some previous studies have suggested that BAL quasars 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 Hbeta FWHM is systematically broader among the FeLoBALQs compared with the non-BAL quasars implying a higher inclination viewing angle or a dearth of low-velocity line-emitting gas.

Resubmitted to ApJ after review

References in corpus (18)

• Some Aspects of Measurement Error in Linear Regression of Astronomical Data
• The Sloan Digital Sky Survey Quasar Catalog: twelfth data release
• The Radius-Luminosity Relationship for Active Galactic Nuclei: The Effect of Host-Galaxy Starlight on Luminosity Measurements
• A Catalog of Broad Absorption Line Quasars in Sloan Digital Sky Survey Data Release 5
• The diversity of quasars unified by accretion and orientation
• A Universal Scaling for the Energetics of Relativistic Jets From Black Hole Systems
• Correcting CIV-Based Virial Black Hole Masses
• The Intrinsic Fraction of Broad Absorption Line Quasars
• Outflows and the Physical Properties of Quasars
• Mining for Dust in Type 1 Quasars
• A Hard X-ray Test of HCN Enhancements as a Tracer of Embedded Black Hole Growth
• An Investigation into the Effects of Luminosity on the Mid-Infrared Spectral Energy Distributions of Radio-Quiet Quasars
• Discovery of a Remarkably Powerful Broad Absorption Line Quasar Outflow in SDSS J135246.37+423923.5
• Near-IR spectroscopy of luminous LoBAL quasars at 1<z<2.5
• Exploring the Diversity of Type 1 Active Galactic Nuclei Identified in SDSS-IV/SPIDERS
• On the origins of C IV absorption profile diversity in broad absorption line quasars
• Variability of Low-ionization Broad Absorption Line Quasars Based on Multi-epoch Spectra from The Sloan Digital Sky Survey
• Placing LOFAR-detected quasars in CIV emission space: implications for winds, jets and star formation

Cited by in corpus (1)

• The Physical Properties of Low Redshift FeLoBAL Quasars. I. Spectral Synthesis Analysis of the BAL Outflows using $SimBAL$