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arXiv · 0904.1374

Feedback through multiple outbursts in the cluster 2A 0335+096

J. S. Sanders·A. C. Fabian·G. B. Taylor
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Abstract

We examine the core of the X-ray bright galaxy cluster 2A 0335+096 using deep Chandra X-ray imaging and spatially-resolved spectroscopy, and include new radio observations. The set of around eight X-ray bright blobs in the core of the cluster, appearing like eggs in a bird's nest, contains multiphase gas from ~0.5 to 2 keV. The morphology of the coolest X-ray emitting gas at 0.5 keV temperature is similar to the Halpha emitting nebula known in this cluster, which surrounds the central galaxy. XMM-Newton grating spectra confirm the presence of material at these temperatures, showing excellent agreement with Chandra emission measures. On scales of 80 to 250 kpc there is a low temperature, high metallicity, swirl of intracluster medium as seen in other clusters. In the core we find evidence for a further three X-ray cavities, in addition to the two previously discovered. Enhancements in 1.5 GHz radio emission are correlated with the X-ray cavities. The total 4PV enthalpy associated with the cavities is around 5x10^59 erg. This energy would be enough to heat the cooling region for ~5x10^7 yr. We find a maximum pressure discontinuity of 26 per cent (2 sigma) across the surface brightness edge to the south-west of the cluster core. This corresponds to an upper limit on the Mach number of the cool core with respect to its surroundings of 0.55.

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J. S. Sanders, A. C. Fabian, G. B. Taylor. 2009-04-08. Feedback through multiple outbursts in the cluster 2A 0335+096. https://doi.org/10.1111/j.1365-2966.2009.14892.x

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