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21. X-Ray Selected High-z AGN Catalog
ID:
ivo://nasa.heasarc/xshzagncxo
Title:
X-Ray Selected High-z AGN Catalog
Short Name:
XSHZAGNCXO
Date:
11 Apr 2025
Publisher:
NASA/GSFC HEASARC
Description:
This table contains the results from an analysis of the largest high-redshift (z > 3) X-ray-selected active galactic nucleus (AGN) sample to date, combining the Chandra Cosmological Evolution Survey and Chandra Multi-wavelength Project surveys and doubling the previous samples. The sample comprises 209 X-ray-detected AGNs, over a wide range of rest-frame 2-10 keV luminosities log L<sub>X</sub> = 43.3 - 46.0 erg/s. X-ray hardness ratios show that ~39 per cent of the sources are highly obscured, N<sub>H</sub> > 10<sup>22</sup> cm<sup>-2</sup>, in agreement with the ~37 per cent of type-2 AGNs found in this sample based on their optical classification. For ~26 per cent of objects, there are mismatched optical and X-ray classifications. Utilizing the 1/V<sub>max</sub> method, the authors confirm that the comoving space density of all luminosity ranges of AGNs decreases with redshift above z > 3 and up to z ~ 7. With a significant sample of AGNs (N = 27) at z > 4, it is found that both source number counts in the 0.5-2 keV band and comoving space density are consistent with the expectation of a luminosity-dependent density evolution (LDDE) model at all redshifts, while they exclude the luminosity and density evolution (LADE) model. The measured comoving space density of type-1 and type-2 AGNs shows a constant ratio between the two types at z > 3. These results for both AGN types at these redshifts are consistent with the expectations of LDDE model. The high-redshift AGN sample used in this work has been selected from the C-COSMOS X-ray catalog, combining the spectroscopic and photometric information available from the identification catalogue of X-ray C-COSMOS sources (Civano et al. 2011, ApJ, 741, 91; 2012, ApJS, 201, 30) and the ChaMP (Chandra Multi-wavelength Project) X-ray catalog using only the 323 ChaMP ObsIDs overlapping with Sloan Digital Sky Survey (SDSS; Richards et al. 2006, AJ, 131, 2766) DR5 imaging. This table was created by the HEASARC in March 2016 based on the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/MNRAS/445/1430">CDS catalog J/MNRAS/445/1430</a> file tablea1.dat. This is a service provided by NASA HEASARC .
22. XTE All-Sky Slew Survey AGN Catalog
ID:
ivo://nasa.heasarc/xteassagn
Title:
XTE All-Sky Slew Survey AGN Catalog
Short Name:
XTEASSAGN
Date:
11 Apr 2025
Publisher:
NASA/GSFC HEASARC
Description:
This table contains the RXTE All-Sky Slew Survey Catalog of AGN and AGN candidates. The catalog authors compiled a sample of 95 AGNs which were serendipitously detected in the 3-20 keV band at Galactic latitude |b| > 10 degrees during the RXTE Slew Survey (XSS, Revnivtsev et al., CDS Cat. <J/A+A/418/927>), and utilized it to study the statistical properties of the local population of AGN, including the X-ray luminosity function and absorption distribution. They find that among low X-ray luminosity (L<sub>X</sub> < 10<sup>43.5</sup> erg/s) AGN, the ratio of absorbed (characterized by intrinsic absorption in the range 10<sup>22</sup> cm<sup>-2</sup> < N<sub>H</sub> < 10<sup>24</sup> cm<sup>-2</sup>) and unabsorbed (N<sub>H</sub> < 10<sup>22</sup> cm<sup>-2</sup>) objects is 2:1, while this ratio drops to less than 1:5 for higher luminosity AGN. The summed X-ray output of AGN with L<sub>X</sub> > 10<sup>41</sup> 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 AGN, non-active galaxies and clusters of galaxies. The authors also presented a sample of 35 AGN candidates, composed of unidentified XSS sources. Most of these AGN belong to the local population (z < 0.1). For each confirmed AGN source, the following information is provided: AGN class, the count rate in two energy bands (3-8 keV and 8-20 keV), the observed and intrinsic (absorption-corrected) luminosity in the 3 - 20keV band, and the intrinsic absorption column density. For the AGN candidates, composed of unidentified XSS sources, the following information is provided: the count rate in two energy bands (3-8 keV and 8-20 keV), the estimated intrinsic absorption column density, and information about RASS Bright Source Catalog and HEAO A-1 X-ray source counterparts. This table was created by the HEASARC in December 2004 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/423/469">CDS Catalog J/A+A/423/469</a>, table1.dat and table2.dat (the corrected version of 01-Dec-2004). This is a service provided by NASA HEASARC .

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