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0.5 Mpc-scale extended X-ray emission in 4C 23.56

O. Johnson·O. Almaini·P. N. Best·J. Dunlop
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Abstract

We present an XMM-Newton observation of the radio galaxy 4C 23.56 at z=2.48 which reveals extended X-ray emission coincident with the radio lobes spanning \~0.5 Mpc. These are the largest X-ray-bright lobes known at z>2. Under the assumption that these features result from inverse-Compton scattering of cosmic microwave background photons by relativistic electrons in the radio source lobes, the measured luminosity of L_0.5-8 keV=7.5x10^44 erg s^-1 implies a minimum energy stored within the lobes of ~10^59 erg. We discuss the potential of the large-scale radio/X-ray lobes to influence evolution of the host galaxy and proto-cluster environment at high redshift.

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O. Johnson, O. Almaini, P. N. Best, J. Dunlop. 2006-08-30. 0.5 Mpc-scale extended X-ray emission in 4C 23.56. https://doi.org/10.1111/j.1365-2966.2006.11358.x

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