Spitzer Number Counts of Active Galactic Nuclei in the GOODS Fields

Abstract

We present mid-infrared observations of AGN in the GOODS fields, performed with the Spitzer Space Telescope. These are the deepest infrared and X-ray fields to date and cover a total area of ~0.1 square degrees. AGN are selected on the basis of their hard (2-8 keV) X-ray emission. The median AGN infrared luminosity is at least 10 times larger than the median for normal galaxies with the same redshift distribution, suggesting that the infrared emission is dominated by the central nucleus. The X-ray to infrared luminosity ratios of GOODS AGN, most of which are at 0.5