On the Merging Cluster Abell 578 and Its Central Radio Galaxy 4C +67.13
  Here we analyze radio, optical, and X-ray data for a peculiar cluster Abell
578. This cluster is not fully relaxed and consists of two merging sub-systems.
The brightest cluster galaxy, CGPG 0719.8+6704, is a pair of interacting
ellipticals with projected separation $\sim$10 kpc, the brighter of which hosts
the radio source 4C +67.13. The Fanaroff-Riley type-II radio morphology of 4C
+67.13 is unusual for central radio galaxies in local Abell clusters. Our new
optical spectroscopy revealed that both nuclei of the CGPG 0719.8+6704 pair are
active, albeit at low accretion rates corresponding to the Eddington ratio
$\sim10^{-4}$ (for the estimated black hole masses of $\sim 3 \times
10^8\,M_\odot$ and $\sim 10^9 \, M_\odot$). The gathered X-ray ({\it Chandra})
data allowed us to confirm and to quantify robustly the previously noted
elongation of the gaseous atmosphere in the dominant sub-cluster, as well as a
large spatial offset ($\sim 60$\,kpc projected) between the position of the
brightest cluster galaxy and the cluster center inferred from the modeling of
the X-ray surface brightness distribution. Detailed analysis of the brightness
profiles and temperature revealed also that the cluster gas in the vicinity of
4C\,+67.13 is compressed (by a factor of about $\sim 1.4$) and heated (from
$\simeq 2.0$\,keV up to 2.7\,keV), consistent with the presence of a weak shock
(Mach number $\sim 1.3$) driven by the expanding jet cocoon. This would then
require the jet kinetic power of the order of $\sim 10^{45}$\,erg\,s$^{-1}$,
implying either a very high efficiency of the jet production for the current
accretion rate, or a highly modulated jet/accretion activity in the system.
