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arXiv · 2012.11610

Peering Into the Extended X-ray Emission on Megaparsec Scale in 3C 187

A. Paggi·F. Massaro·H. A. Pena-Herazo·V. Missaglia·F. Ricci·C. Stuardi·R. P. Kraft·G. R. Tremblay·S. A. Baum·B. J. Wilkes
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Abstract

Context. The diffuse X-ray emission surrounding radio galaxies is generally interpreted either as due to inverse Compton scattering of non-thermal radio-emitting electrons on the Cosmic Microwave Background (IC/CMB), or as the thermal emission arising from the hot gas of the intergalactic medium (IGM) permeating galaxy clusters hosting such galaxies, or as a combination of both. In this work we present an imaging and spectral analysis of Chandra observations for the radio galaxy 3C 187 to investigate its diffuse X-ray emission and constrain the contribution of these different physical mechanisms. Aims. The main goals of this work are: (i) to evaluate the extension of the diffuse X-ray emission from this source, (ii) to investigate the two main processes that can account for its origin - IC/CMB and thermal emission from the IGM - and (iii) to test the possibility for 3C 187 to belong to a cluster of galaxies, that can account for the observed diffuse X-ray emission. Methods. To evaluate the extension of the X-ray emission around 3C 187 we extracted surface flux profiles along and across the radio axis. We also extracted X-ray spectra in the region of the radio lobes and in the cross-cone region to estimate the contribution of the non-thermal (IC/CMB) and thermal (IGM) processes to the observed emission, making use of radio (VLA and GMRT) data to investigate the multi-wavelength emission arising from the lobes. We collected Pan-STARRS photometric data to investigate the presence of a galaxy cluster hosting 3C 187, looking for the presence of a "red sequence" in the source field in the form of a tight clustering of the galaxies in the color space...

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A. Paggi, F. Massaro, H. A. Pena-Herazo, V. Missaglia, F. Ricci, C. Stuardi, R. P. Kraft, G. R. Tremblay, S. A. Baum, B. J. Wilkes. 2020-12-21. Peering Into the Extended X-ray Emission on Megaparsec Scale in 3C 187. https://doi.org/10.1051/0004-6361/202039813

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