Statistical properties of local active galactic nuclei inferred from the   RXTE 3-20 keV all-sky survey
  We compiled a sample of 95 AGNs serendipitously detected in the 3-20 keV band at Galactic latitude |b|>10 during the RXTE slew survey (XSS, Revnivtsev et al.), and utilize it to study the statistical properties of the local population of AGNs, including X-ray luminosity function and absorption distribution. We find that among low X-ray luminosity (Lx < 10^43.5 erg/s) AGNs, the ratio of absorbed (characterized by intrinsic absorption in the range 10^22 cm^-2 < NH < 10^24 cm^-2) and unabsorbed (NH < 10^22 cm^-2) objects is 2:1, while this ratio drops to less than 1:5 for higher luminosity AGNs. The summed X-ray output of AGNs with Lx > 10^41 erg/s estimated here is smaller than the earlier estimated total X-ray volume emissivity in the local Universe, suggesting that a comparable X-ray flux may be produced together by lower luminosity AGNs, non-active galaxies and clusters of galaxies. Finally, we present a sample of 35 AGN candidates, composed of the unidentified XSS sources. 
S. Sazonov, M. Revnivtsev