We present the optical-near infrared spectral energy distributions (SED) and
near infrared variability properties of 30 low-redshift iron low-ionization
Broad Absorption Line quasars (FeLoBALQs) and matched samples of LoBALQs and
unabsorbed quasars. Significant correlations between the SED properties and
accretion rate indicators found among the unabsorbed comparison sample objects
suggest an intrinsic origin for SED differences. A range of reddening likely
mutes these correlations among the FeLoBAL quasars. The restframe optical-band
reddening is correlated with the location of the outflow, suggesting a link
between the outflows and the presence of dust. We analyzed WISE variability and
provide a correction for photometry uncertainties in an appendix. We found an
anticorrelation between the variability amplitude and inferred continuum
emission region size, and suggest that as the origin of the anticorrelation
between variability amplitude and luminosity typically observed in quasars. We
found that the LoBALQ optical emission line and other parameters are more
similar to those of the unabsorbed continuum sample objects than the FeLoBALQs.
Thus, FeLoBAL quasars are a special population of objects. We interpret the
results using an accretion-rate scenario for FeLoBAL quasars. The high
accretion rate FeLoBAL quasars are radiating powerfully enough to drive a
thick, high-velocity outflow. Quasars with intermediate accretion rates may
have an outflow, but it is not sufficiently thick to include FeII absorption.
Low accretion rate FeLoBAL outflows originate in absorption in a failing torus,
no longer optically thick enough to reprocess radiation into the near-IR.
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Title
The Physical Properties of Low Redshift FeLoBAL Quasars. IV. Optical-Near IR Spectral Energy Distributions and Near-IR Variability Properties