Data · dataset · 2025
X-Ray Selected High-z AGN Catalog
Listed in NASA Data Portal
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.
Description
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.
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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="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 .
Links
Get the data
- Resource heasarc.gsfc.nasa.gov/W3Browse/all/xshzagncxo.html ↗
download · from data nasa gov
- Resource heasarc.gsfc.nasa.gov/xamin/vo/cone?showoffsets=&table=xshzagncxo ↗
download · from data nasa gov
Where it is published
- NASA Data Portal dataset page data.nasa.gov/dataset/x-ray-selected-high-z-agn-catalog ↗
landing page · from data nasa gov
Catalogue records · 1
- CKAN API data.nasa.gov/api/3/action/package_show?id=2aad5f99-605c-4efe-ac8b-4b567a010… ↗
metadata API · from data nasa gov
Topics
Provenance · 1 source records, 8 field assertions
| Source | Key | Last seen | Raw |
|---|---|---|---|
| NASA Data Portal | 2aad5f99-605c-4efe-ac8b-4b567a010c85 | 11 d ago | JSON v1 |
| Field | Assertion | Extractor | Evidence |
|---|---|---|---|
| concepts[modality].local:modality:imaging | enrichment · data nasa gov | keyword-concept-rules@1.0.0 | title+description (75%) |
| concepts[modality].local:modality:tabular | enrichment · data nasa gov | keyword-concept-rules@1.0.0 | title+description (65%) |
| created_date | source · data nasa gov | connector:data_nasa_gov@1.0.0 | |
| description | source · data nasa gov | connector:data_nasa_gov@1.0.0 | /notes |
| license_text | source · data nasa gov | connector:data_nasa_gov@1.0.0 | |
| publication_date | source · data nasa gov | connector:data_nasa_gov@1.0.0 | |
| title | source · data nasa gov | connector:data_nasa_gov@1.0.0 | /title |
| updated_date | source · data nasa gov | connector:data_nasa_gov@1.0.0 |