AGN feedback and iron enrichment in the powerful radio galaxy, 4C+55.16
  We present a detailed X-ray analysis of 4C+55.16, an unusual and interesting
radio galaxy, located at the centre of a cool core cluster of galaxies.
4C+55.16 is X-ray bright (L(cluster)~10^45 erg/s), radio powerful, and shows
clear signs of interaction with the surrounding intracluster medium. By
combining deep Chandra (100 ks) with 1.4 GHz VLA observations, we find evidence
of multiple outbursts from the central AGN, providing enough energy to offset
cooling of the ICM (P_bubbles=6.7x10^44 erg/s). Furthermore, 4C+55.16 has an
unusual intracluster iron distribution showing a plume-like feature rich in Fe
L emission that runs along one of the X-ray cavities. The excess of iron
associated with the plume is around 10^7M_sol. The metal abundances are
consistent with being Solar-like, indicating that both SNIa and SNII contribute
to the enrichment. The plume and southern cavity form a region of cool
metal-rich gas, and at the edge of this region, there is a clear discontinuity
in temperature (from kT~2.5 keV to kT~5.0 keV), metallicity (from ~0.4 solar to
0.8 solar), and surface brightness distribution, consistent with it being
caused by a cold front. However, we also suggest that this discontinuity could
be caused by cool metal-rich gas being uplifted from the central AGN along one
of its X-ray cavities.
