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The density of extremely red objects around high-z radio-loud AGN

A. Cimatti·D. Villani·L. Pozzetti·S. di Serego Alighieri
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Abstract

We present the results of a K-band imaging survey of 40 arcmin^{2} in fields around 14 radio-loud AGN (6 radio galaxies and 8 quasars) with z>1.5. The survey, 80% complete to K<19.2 and complemented by R-band imaging, aimed at investigating whether extremely red objects (EROs) are present in excess around high-z AGN, and to study the environment of z>1.5 radio galaxies and radio-loud quasars. At $18 6 compared to the general field. Consistently, we also find that the R-K colour distribution of all the galaxies in the AGN fields are significantly redder than the colour distribution of the field galaxies. On the other hand, the distribution of the R-K colours is undistinguishable from that of galaxies taken from literature fields around radio-loud quasars at 1<z<2. We discuss the main implications of our findings and we compare the possible scenarios which could explain our results.

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A. Cimatti, D. Villani, L. Pozzetti, S. di Serego Alighieri. 2000-06-01. The density of extremely red objects around high-z radio-loud AGN. https://doi.org/10.1046/j.1365-8711.2000.03736.x

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