Satellites of Radio AGN in SDSS: Insights into AGN Triggering and
  Feedback
  We study the effects of radio jets on galaxies in their vicinity (satellites)
and the role of satellites in triggering radio-loud active galactic nuclei
(AGNs). The study compares the aggregate properties of satellites of a sample
of 7,220 radio AGNs at z < 0.3 (identified by Best & Heckman 2012 from the SDSS
and NVSS+FIRST surveys) to the satellites of a control sample of radio-quiet
galaxies, which are matched in redshift, color, luminosity, and axis ratio, as
well as by environment type: field galaxies, cluster members and brightest
cluster galaxies (BCGs). Remarkably, we find that radio AGNs exhibit on average
a 50% excess (17{\sigma} significance) in the number of satellites within 100
kpc even though the cluster membership was controlled for (e.g., radio BCGs
have more satellites than radio-quiet BCGs, etc.). Satellite excess is not
confirmed for high-excitation sources, which are only 2% of radio AGN. Extra
satellites may be responsible for raising the probability for hot gas AGN
accretion via tidal effects or may otherwise enhance the intensity or duration
of the radio-emitting phase. Furthermore, we find that the incidence of radio
AGNs among potential hosts (massive ellipticals) is similar for field galaxies
and for non-BCG cluster members, suggesting that AGN fueling depends primarily
on conditions in the host halo rather than the parent, cluster halo. Regarding
feedback, we find that radio AGNs, either high or low excitation, have no
detectable effect on star formation in their satellites, as neither induced
star formation nor star formation quenching is present in more than ~1% of
radio AGN.
