CHAMP: 188 Hard X-Ray Emitting Active Galactic Nuclei from Chandra

188 active galactic nuclei (AGN) were identified from 497 hard X-ray sources in 20 Chandra fields. The data was created by NASA HEASARC in March 2007 based on the CDS table J/ApJ/618/123. The sample is based on X-ray and optical analysis to study sources responsible for the cosmic X-ray background.

Use Cases

• Classifying AGN types based on X-ray luminosity and optical signatures mentioned in the description
• Studying the composition of the 2-8 keV cosmic X-ray background based on the representative subset of sources
• Analyzing the relationship between X-ray flux and optical brightness for AGN selection
• Investigating obscured AGN populations where traditional optical signatures are absent, using high X-ray luminosity as a discriminant

Strengths

• Sample of 188 AGN derived from 497 hard X-ray sources across 20 Chandra fields
• Achieves 77% completeness for X-ray sources with optical counterparts brighter than r' < 22.5
• Provides detailed breakdown of source classifications: broad-line AGN (62%), narrow-line galaxies (24%), absorption-line galaxies (7%), stars (5%), clusters (2%)

Limitations

• Column-level documentation is absent; field semantics must be inferred after download
• Row count is unknown, which may limit suitability assessment

Provenance

Source

NASA HEASARC, based on CDS table J/ApJ/618/123

Collection Method

X-ray and optical analysis of Chandra Multiwavelength Project (ChaMP) observations

Time Range

Observational data from the Chandra Multiwavelength Project; table created March 2007

Freshness

Last updated 2026-03-13 18:57:22.045715; freshness should be verified

Geography

Observations from 20 Chandra fields covering 1.5 square degrees