X-ray luminosity functions of different morphological and X-ray type AGN populations

Abstract

Luminosity functions are one of the most important observational clues when studying galaxy evolution over cosmic time. In this paper we present the X-ray luminosity functions for X-ray detected AGN in the SXDS and GWS fields. The limiting fluxes of our samples are 9.0 ×10^(-15) and 4.8 ×10^(-16) erg cm^(-2) s^(-1) in the 0.5-7.0 keV band in the two fields, respectively. We carried out analysis in three X-ray bands and in two redshift intervals up to z≤1.4. Moreover, we derive the luminosity functions for different optical morphologies and X-ray types. We confirm strong luminosity evolution in all three bands, finding the most luminous objects at higher redshift. However, no signs of density evolution are found in any tested X-ray band. We obtain similar results for compact and early-type objects. Finally, we observe the “Steffen effect", where X-ray type-1 sources are more numerous at higher luminosities in comparison with type-2 sources.