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The evolution of AGNs in the Hard X-Rays and the Infrared

F. La Franca·I. Matute·F. Fiore·C. Gruppioni·F. Pozzi·C. Vignali plus HELLAS·ELAIS collaborations
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Abstract

We present the estimate of the evolution of type 1 AGNs in the hard (2-10 keV) X-rays drawn from the HELLAS survey, and in the IR (15um) obtained from the ELAIS survey. We find that the local luminosity function (LF) of AGN1 in the 2-10 keV band is fairly well represented by a double-power-law-function. There is evidence for significant cosmological evolution according to a pure luminosity evolution model Lx(z)~(1+z)^k, with k=2.12 and k=2.19 in a (Omega_m,Omega_lambda)=(1.0,0.0) and in a (Omega_m,Omega_lambda)=(0.3,0.7) cosmology respectively. In a (Omega_m,Omega_lambda)=(1.0,0.0) Universe the data show an excess of faint high redshift type 1 AGN which is well modeled by a luminosity dependent density evolution, similarly to what observed in the soft X-rays. In the IR band, with a (Omega_m,Omega_lambda)=(1.0,0.0) cosmology, the evolution found is similar to what observed in other wavebands, the LF is a double-power-law-function with a bright slope 2.9 and a faint slope 1.1, following a luminosity evolution model L(z)~(1+z)^3.0.

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F. La Franca, I. Matute, F. Fiore, C. Gruppioni, F. Pozzi, C. Vignali plus HELLAS, ELAIS collaborations. 2001-11-07. The evolution of AGNs in the Hard X-Rays and the Infrared. https://arxiv.org/abs/astro-ph/0109308

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