Stormy weather in 3C 196.1: nuclear outbursts and merger events shape
  the environment of the hybrid radio galaxy 3C 196.1
  We present a multi-wavelength analysis based on archival radio, optical and
X-ray data of the complex radio source 3C 196.1, whose host is the brightest
cluster galaxy of a $z=0.198$ cluster. HST data show H$\alpha$+[N II] emission
aligned with the jet 8.4 GHz radio emission. An H$\alpha$+[N II] filament
coincides with the brightest X-ray emission, the northern hotspot. Analysis of
the X-ray and radio images reveals cavities located at galactic- and cluster-
scales. The galactic-scale cavity is almost devoid of 8.4 GHz radio emission
and the south-western H$\alpha$+[N II] emission is bounded (in projection) by
this cavity. The outer cavity is co-spatial with the peak of 147 MHz radio
emission, and hence we interpret this depression in X-ray surface brightness as
being caused by a buoyantly rising bubble originating from an AGN outburst
$\sim$280 Myrs ago. A \textit{Chandra} snapshot observation allowed us to
constrain the physical parameters of the cluster, which has a cool core with a
low central temperature $\sim$2.8 keV, low central entropy index $\sim$13 keV
cm$^2$ and a short cooling time of $\sim$500 Myr, which is $<0.05$ of the age
of the Universe at this redshift. By fitting jumps in the X-ray density we
found Mach numbers between 1.4 and 1.6, consistent with a shock origin. We also
found compelling evidence of a past merger, indicated by a morphology
reminiscent of gas sloshing in the X-ray residual image. Finally, we computed
the pressures, enthalpies $E_{cav}$ and jet powers $P_{jet}$ associated with
the cavities: $E_{cav}\sim7\times10^{58}$ erg, $P_{jet}\sim1.9\times10^{44}$
erg s$^{-1}$ for the inner cavity and $E_{cav}\sim3\times10^{60}$ erg,
$P_{jet}\sim3.4\times10^{44}$ erg s$^{-1}$ for the outer cavity.
