Galaxy overdensities around 3C radio galaxies and quasars at 1 < z < 2.5 revealed by Spitzer 3.6/4.5 µm and Pan‐STARRS

Luminous radio sources are thought to lie in galaxy clusters or proto-clusters. The complete sample of 64 high-redshift 3C sources at 1 3 sigma) within 30 (approximate to 250kpc) projected distance from the radio source compared to the surrounding galaxy densities measured in the 50-120 annulus. The Pan-STARRS/IRAC cut reveals higher average overdensities than the IRAC1/2 cut and also a decline of overdensities at z>1.4. To infer the nature of the cluster members, we rerun the analysis using a stronger IRAC1/2 cut [3.6]-[4.5]<-0.1, which removes 1更多