The Massive and Distant Clusters of WISE Survey. IV. The Distribution of Active Galactic Nuclei in Galaxy Clusters at z?～?1

摘要

We present an analysis of the radial distribution of active galactic nuclei (AGNs) in 2300 galaxy clusters from the Massive and Distant Clusters of Wide-field Infrared Survey Explorer Survey (MaDCoWS). MaDCoWS provides the largest coverage of the extragalactic sky for a cluster sample at z?~?1. We use literature catalogs of AGNs selected via optical, midinfrared (MIR), and radio data, and by optical-to-MIR (OIR) color. Stacking the radial distribution of AGNs within the 6' of the centers of MaDCoWS galaxy clusters, we find a distinct overdensity of AGNs within 1' of the galaxy cluster center for AGNs of all selection methods. The fraction of red galaxies that host AGNs as a function of clustercentric distance is, however, dependent on the AGN selection. The fraction of red galaxies in cluster environments that host AGNs selected by optical signatures or blue OIR color is at a deficit compared to the field, whereas MIR-selected and red OIR color AGNs are enhanced in the centers of clusters when compared to field levels. The radio-selected AGN fraction is more than 2.5 times that of the field, implying that the centers of clusters are conducive to the triggering of radio emission in AGNs. We do not find a statistically significant change in the AGN fraction as a function of cluster richness. We also investigate the correlation of central radio activity with other AGNs in galaxy clusters. Clusters with radio activity have more central AGNs than do radio-inactive clusters, implying that central cluster radio activity and AGN triggering may be linked.