On the diversity of the jet production efficiency in Swift/BAT AGNs
  We address the very large diversity of the jet production efficiency in
active galactic nuclei (AGNs) by using data on low redshift AGNs selected from
the Swift/BAT catalog and having black hole (BH) masses larger than
$10^{8.5}\,M_{\odot}$. Most of these AGNs accrete at intermediate rates and
have bolometric luminosities dominated by mid-IR radiation. Our sample contains
$14\%$ radio-loud (RL), $6\%$ radio-intermediate (RI), and $80\%$ radio-quiet
(RQ) AGNs. All RL objects are found to have extended radio structures and most
of them have classical FR II morphology. Converting their radio loudness to the
jet production efficiency, we find that the median of this efficiency is on the
order of $(\epsilon_d/0.1)\%$, where $\epsilon_d=L_{\rm bol}/\dot{M}c^2$ is the
radiation efficiency of the accretion disk. Without knowing the contribution of
jets to the radio emission in the RQ AGNs, we are only able to estimate their
efficiencies using upper limits. Their median is found to be
$0.002(\epsilon_d/0.1)\%$. Our results suggest that some threshold conditions
must be satisfied to allow production of strong, relativistic jets in RL AGNs.
We discuss several possible scenarios and argue that the production of
collimated, relativistic jets must involve the Blandford-Znajek mechanism and
can be activated only in those AGNs whose lifetime is longer than the time
required to enter the magnetically arrested disk (MAD). Presuming that MAD is
required to collimate relativistic jets, we expect that the weak
nonrelativistic jets observed in some RQ AGNs are produced by accretion disks
rather than by rotating BHs.
