Multiwavelength Comparison of X-ray and Infrared Selected Active Galactic Nuclei

Active galactic nuclei emit energy across the entire electromagnetic spectrum. Using only one wavelength region to identify AGNs may miss sources with unique characteristics. In this work, we compare the multiwavelength properties of X-ray and infrared (IR) selected AGN in the COSMOS field for z<6. Our X-ray-selected AGN sample includes all sources with a 0.5-10 keV X-ray luminosity greater than 10⁴³ erg s^-1. We define our IR-selected AGN sample using the four Spitzer/IRAC channels. We find that both selection methods miss a significant fraction of AGNs that are identified using the competing method. X-ray AGN selection is able to capture the most diverse range of multiwavelength emission properties, but misses a fraction of heavily obscured AGNs. Meanwhile, IR AGN selection is generally biased towards more powerful, dusty AGNs.