A Search for Blazar Activity in Broad-Absorption-Line Quasars
  Our recently reported lack of Intra-Night Optical Variability (INOV) among
Broad-Absorption-Line (BAL) quasars exhibiting some blazar-like radio
properties, either questions polar ejection of BAL clouds, and/or hints at a
physical state of the relativistic jet modified due to interaction with the
thermal BAL wind on the innermost sub-parsec scale. As a robust check on this
unexpected finding for the BAL_blazar candidates, we report here the INOV study
of a new and much more rigorously defined comparison sample consisting of 9
normal (non-BAL) blazars, matched in both magnitude and redshift to the
aforementioned sample of BAL_blazar candidates. The present campaign spanning
27 sessions yields an INOV duty cycle of ~23% for the comparison sample of
normal blazars, employing the enhanced F-test. However, even this more
sensitive test does not detect INOV for the sample of BAL_blazar candidates.
This stark INOV contrast found here between the BAL_blazar candidates and
normal blazars can probably be traced to a physical interaction of the
relativistic jet with the thermal wind, within sub-parsec range from the
nucleus. The consequent enfeebling of the jet would additionally explain the
striking deficiency among BAL quasars of powerful FR II radio lobes on the much
larger scale of 10-100 kpc.
