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We present results from a deep Chandra observation of Abell 2052. A2052 is a bright, nearby, cooling flow cluster, at a redshift of z=0.035. Concentric surface brightness discontinuities are revealed in the cluster center, and these features are consistent with shocks driven by the AGN, both with Mach numbers of approximately 1.2. The southern cavity in A2052 now appears to be split into two cavities with the southernmost cavity likely representing a ghost bubble from earlier radio activity. There also appears to be a ghost bubble present to the NW of the cluster center. The cycle time measured for the radio source is t ≈ 2 × 10 7 yr using either the shock separation or the rise time of the bubbles. The energy deposited by the radio source, including a combination of direct shock heating and heating by buoyantly rising bubbles inflated by the AGN, can offset the cooling in the core of the cluster.

We present new radio and X-ray observations of Abell 262. The X-ray residual image provides the first evidence of an X-ray tunnel in this system while the radio data reveal that the central radio source is more than three times larger than previously known. We find that the well-known cluster-center Sshaped radio source B2 0149+35 is surrounded by extended emission to the east and south-west. The south-western extension is co-spatial with the X-ray tunnel seen in our new Chandra images while the eastern extension shows three clumps of emission with the innermost coincident with a faint X-ray cavity. The outer two eastern radio extensions are coincident with a newly detected X-ray depression. We use the projected separation of the emission regions to estimate a lower limit of τ rep = 28 Myr to the outburst repetition timescale of the central AGN. The total energy input into the cluster over multiple outburst episodes is estimated to be 2.2 × 10 58 ergs, more than an order of magnitude larger than previously thought. The total AGN energy output determined from our new observations shows that the source should be capable of offsetting radiative cooling over several outburst episodes.

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