The distribution of galactic neighbours of X-ray-selected active galactic nuclei

ABSTRACT We combine X-ray data from the X-ray Multi-Mirror Mission 12th data release (4XMM DR12) and the extended ROentgen Survey with an Imaging Telescope Array (eROSITA) Final Equatorial-Depth Survey (eFEDS) early data release catalogues with the Galaxy and Mass Assembly spectroscopic galaxy survey to form a sample of 526 local ($0.05\le z \le 0.3$), moderately luminous active galactic nuclei (AGNs; $L_{\rm X} \ge 10^{42}$ erg s-1). We compare the distribution of AGN hosts with that of the general galaxy population, finding no evidence of AGNs being preferentially hosted within over/underdense environments at a 7-Mpc scale. Next, we compare the distances to nearest-neighbour galaxies and find that AGN host galaxies are separated from their neighbours by the same distance as galaxies in a matched non-AGN sample. Finally, we consider mid-IR colour, provided by the All-WISE survey, the $L_{\rm X}/L_{6\, \mu \mathrm{m}}$ ratio, and X-ray hardness as tracers of AGN obscuration, to explore whether there is a change in the galaxy environment for obscured AGNs. We find no evidence of increasing AGN obscuration with decreasing separation in close galaxy pairs. We conclude that close galaxy–galaxy interactions may not be sufficiently disruptive to cause any observable increase in AGN activity.