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arXiv · astro-ph/9802139

Galaxies and clusters around and in front of radio sources

M. Lacy
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Abstract

Some recent work on radio source fields at z~0.7 and z~4 is discussed. At z~0.7 we find that radio-loud quasars are typically found in moderately rich environments independent of radio luminosity, consistent with previous results at z~0.5. In the field of the z=4.41 radio galaxy 6C0140+326 we find several candidate z>4 galaxies using the Lyman-break technique, two of which have detectable UV absorption features. In two z>4 radio galaxies, we find evidence for gravitational lensing affecting the fluxes by a few tens of percent, although we cannot rule out unusual lensing events which have larger magnifications associated with them. A simple calculation suggests lensing of z>4 radio sources should be very common.

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M. Lacy. 1998-02-11. Galaxies and clusters around and in front of radio sources. https://arxiv.org/abs/astro-ph/9802139

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