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Discovery of an overdensity of faint red galaxies in the vicinity of the z=1.786 radio galaxy 3C 294

S. Toft·K. Pedersen·H. Ebeling·J. Hjorth
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Abstract

We report the discovery of an overdensity of faint red galaxies in the vicinity of the z=1.786 radio galaxy 3C 294. The overdensity, discovered in a 84 min Ks-band ISAAC/VLT image is significant at the 2.4 sigma level (compared to the local field density), and overlaps with the extended X-ray emission around 3C 294 detected with the Chandra X-ray Observatory. The near-infrared colours of the galaxies making up the overdensity show a large scatter and the galaxies do not follow a red sequence in the colour magnitude diagram. If the galaxies are in a cluster at z=1.786 they must be dominated by young stellar populations with different star-formation histories.

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S. Toft, K. Pedersen, H. Ebeling, J. Hjorth. 2003-03-31. Discovery of an overdensity of faint red galaxies in the vicinity of the z=1.786 radio galaxy 3C 294. https://doi.org/10.1046/j.1365-8711.2003.06678.x

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