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The Phoenix survey: the pairing fraction of faint radio sources

A. Georgakakis·B. Mobasher·L. Cram·A. Hopkins
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Abstract

The significance of tidal interactions in the evolution of the faint radio population (sub-mJy) is studied using a deep and homogeneous radio survey (1.4 GHz), covering an area of 3.14 deg$^2$ and complete to a flux density of 0.4 mJy. Optical photometric and spectroscopic data are also available for this sample. A statistical approach is employed to identify candidate physical associations between radio sources and optically selected `field' galaxies. We find an excess of close pairs around optically identified faint radio sources, albeit at a low significance level, implying that the pairing fraction of the sub-mJy radio sources is similar to that of `field' galaxies (at the same magnitude limit) but higher than that of local galaxies.

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A. Georgakakis, B. Mobasher, L. Cram, A. Hopkins. 1999-10-07. The Phoenix survey: the pairing fraction of faint radio sources. https://doi.org/10.1046/j.1365-8711.1999.03141.x

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