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Title: The Physical Properties of Low-redshift FeLoBAL Quasars. III. The Location and Geometry of the Outflows
Abstract We present continued analysis of a sample of low-redshift iron low-ionization broad-absorption-line quasars (FeLoBALQs). Choi et al. presented SimBAL spectral analysis of broad-absorption-line (BAL) outflows in 50 objects. Leighly et al. analyzed the optical emission lines of 30 of those 50 objects and found that they are characterized by either a high accretion rate ( L Bol / L Edd > 0.3) or low accretion rate (0.03 < L Bol / L Edd < 0.3). We report that the outflow velocity is inversely correlated with the BAL location among the high-accretion-rate objects, with the highest velocities observed in parsec-scale outflows. In contrast, the low-Eddington-ratio objects showed the opposite trend. We confirmed the known relationship between the outflow velocity and L Bol / L Edd and found that the scatter plausibly originates in the force multiplier (launch radius) in the low(high)-accretion-rate objects. A log volume filling factor between −6 and −4 was found in most outflows but was as high as −1 for low-velocity compact outflows. We investigated the relationship between the observed [O iii ] emission and that predicted from the BAL gas. We found that these could be reconciled if the emission-line covering fraction depends on the Seyfert type and BAL location. The difference between the predicted and observed [O iii ] luminosity is correlated with the outflow velocity, suggesting that [O iii ] emission in high-Eddington-ratio objects may be broad and hidden under Fe ii emission. We suggest that the physical differences in the outflow properties as a function of location in the quasar and accretion rate point to different formation, acceleration, and confinement mechanisms for the two FeLoBALQ types.  more » « less
Award ID(s):
2006771 1518382 2007023
PAR ID:
10432992
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
936
Issue:
2
ISSN:
0004-637X
Page Range / eLocation ID:
110
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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