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arXiv · 1412.8632

X-ray cavities and temperature jumps in the environment of the strong cool core cluster Abell 2390

S. S. Sonkamble·N. D. Vagshette·P. K. Pawar·M. K. Patil
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Abstract

We present results based on the systematic analysis of high resolution 95 ks Chandra observations of the strong cool core cluster Abell 2390 at the redshift of z= 0.228 that hosts an energetic radio AGN. This analysis has enabled us to investigate five X-ray deficient cavities in the atmosphere of Abell 2390 within central 30". Presence of these cavities have been confirmed through a variety of image processing techniques like, the surface brightness profiles, unsharp masked image, as well as 2D elliptical model subtracted residual map. Temperature profile as well as 2D temperature map revealed structures in the distribution of ICM, in the sense that ICM in the NW direction is cooler than that on the SE direction. Temperature jump in all directions is evident near 25" (90.5 kpc) corresponding to the average Mach number 1.44$\pm$0.05, while another jump from 7.47 keV to 9.10 keV at 68" (246 kpc) in the north-west direction, corresponding to Mach number 1.22$\pm$0.06 and these jumps are associated with the cold fronts. Tricolour map as well as hardness ratio map detects cool gas clumps in the central 30 kpc region of temperature $4.45_{-0.10}^{+0.16}$ keV. The entropy profile derived from the X-ray analysis is found to fall systematically inward in a power-law fashion and exhibits a floor near 12.20$\pm$2.54 keV cm$^2$ in the central region. This flattening of the entropy profile in the core region confirms the intermittent heating at the centre by AGN. The diffuse radio emission map at 1.4\,GHz using VLA L-band data exhibits highly asymmetric morphology with an edge in the north-west direction coinciding with the X-ray edge seen in the unsharp mask image.

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S. S. Sonkamble, N. D. Vagshette, P. K. Pawar, M. K. Patil. 2014-12-30. X-ray cavities and temperature jumps in the environment of the strong cool core cluster Abell 2390. https://doi.org/10.1007/s10509-015-2508-z

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