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Chandra X-ray observations of the 3C295 cluster core

S. W. Allen·G. B. Taylor·P. E. J. Nulsen·R. M. Johnstone·L. P. David·S. Ettori·A. C. Fabian·W. Forman·C. Jones·B. McNamara
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Abstract

We examine the properties of the X-ray gas in the central regions of the distant (z=0.46), X-ray luminous cluster of galaxies surrounding the powerful radio source 3C 295, using observations made with the Chandra Observatory. Between radii of 50-500 kpc, the cluster gas is approximately isothermal with an emission-weighted temperature, kT ~5 keV. Within the central 50 kpc radius this value drops to kT ~3.7 keV. The spectral and imaging Chandra data indicate the presence of a cooling flow within the central 50 kpc radius of the cluster, with a mass deposition rate of approximately 280 solar masses per year. We estimate an age for the cooling flow of 1-2 Gyr, which is approximately one thousand times older than the central radio source. We find no evidence in the X-ray spectra or images for significant heating of the X-ray gas by the radio source. We report the detection of an edge-like absorption feature in the spectrum for the central 50 kpc region, which may be due to oxygen-enriched dust grains. The implied mass in metals seen in absorption could have been accumulated by the cooling flow over its lifetime. Combining the results on the X-ray gas density profile with radio measurements of the Faraday rotation measure in 3C295, we estimate the magnetic field strength in the region of the cluster core to be B ~12 \muG.

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S. W. Allen, G. B. Taylor, P. E. J. Nulsen, R. M. Johnstone, L. P. David, S. Ettori, A. C. Fabian, W. Forman, C. Jones, B. McNamara. 2001-01-10. Chandra X-ray observations of the 3C295 cluster core. https://doi.org/10.1046/j.1365-8711.2001.04315.x

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