Extragalactic hard X-ray source counts with INTEGRAL observatory: A Progress Report

Abstract

We present results from the hard X-ray sky survey being performed with INTEGRAL observatory. During two years of operation the significant sky area was covered with moderate sensitivity which now allows us to estimate surface number density of Active Galactic Nuclei (AGN) in hard (17-60 keV) energy band. Our catalog of detected sources comprises $>60$ AGN with wide range of intrinsic absorption. We used $24000 deg^{2}$ sky coverage (high Galactic latitude observations) with total exposure $>2$ Msec to derive source number-flux relation. The estimated surface density of extragalactic hard X-ray sources with flux $>10^{-11}$ erg s$^{-1}$ cm$^{-2}$ is $(1.0 \pm 0.5) 10^{-2} deg^{-2}$.