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arXiv · 1609.02178

The environment of radio sources in the VLA-COSMOS Survey field

Nicola Malavasi·Sandro Bardelli·Paolo Ciliegi·Olivier Ilbert·Lucia Pozzetti·Elena Zucca
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Abstract

This work studies the correlation among environmental density and radio AGN presence up to $z = 2$. Using data from the photometric COSMOS survey and its radio 1.4 GHz follow-up (VLA-COSMOS), a sample of radio AGNs has been defined. The environment was studied using the richness distributions inside a parallelepiped with base side of 1 Mpc and height proportional to the photometric redshift precision. Radio AGNs are found to be always located in environments significantly richer than those around galaxies with no radio emission. Moreover, a distinction based on radio AGN power shows that the significance of the environmental effect is only maintained for low-power radio sources. The results of this work show that denser environments play a significant role in enhancing the probability that a galaxy hosts a radio AGN and, in particular, low-power ones.

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Nicola Malavasi, Sandro Bardelli, Paolo Ciliegi, Olivier Ilbert, Lucia Pozzetti, Elena Zucca. 2016-09-07. The environment of radio sources in the VLA-COSMOS Survey field. https://doi.org/10.1007/978-3-319-19330-4_17

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