ChandraObservation of the Cooling Flow Cluster Abell 2052

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Abstract
We present an analysis of the Chandra X-ray observation of A2052, including large-scale properties of the cluster as well as the central region, which includes the bright radio source 3C 317. We present temperature and abundance profiles using both projected and deprojected spectral analyses. The cluster shows the cooling flow signatures of excess surface brightness above a β-model at the cluster center and a temperature decline into the center of the cluster. For A2052, the temperature drops by a factor of 3 from approximately 3 to 1 keV. The heavy-element abundances initially increase into the center, but decline within 30''. Temperature and abundance maps show that the X-ray-bright shells surrounding the radio source are the coolest and least abundant regions in the cluster. The mass deposition rate in the cooling flow is 26 M☉ yr-1 < < 42 M☉ yr-1. This rate is approximately a factor of 3 lower than the rates found with previous X-ray observatories. Based on a stellar population analysis using imaging and spectra at wavelengths spanning the far-ultraviolet to the near-infrared, we find a star formation rate of 0.6 M☉ yr-1 within a 3'' radius of the nucleus of the central cluster galaxy. Total and gas mass profiles for the cluster are also determined. We investigate additional sources of pressure in the X-ray holes formed by the radio source and limit the temperature of any hot, diffuse, thermal component that provides the bulk of the pressure in the holes to kT 20 keV. We calculate the magnetic field in the bright-shell region and find B ≈ 11 μG. The magnetic pressure in the cluster center is significantly lower than the gas pressure. The current luminosity of the central AGN is LX = 7.9 × 1041 ergs s-1, and its spectrum is well fitted by a power-law model with no excess absorption above the Galactic value. The energy output from several radio outbursts, occurring episodically over the lifetime of the cluster, may be sufficient to offset the cooling flow near the center.
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