Lockman Hole AGN Catalog: Optical and Infrared Properties for 409 X-ray Sources

401 counterparts were identified for X-ray sources in the Lockman Hole using optical, near-infrared, and mid-infrared catalogs. The catalog contains accurate photometry from U to 24 microns for 377 AGN and 32 other objects, created by NASA HEASARC in 2012. X-ray observations were conducted by XMM-Newton between 2000 and 2002, with optical data from the Large Binocular and Subaru telescopes.

Use Cases

• Classify AGN-dominated versus host-dominated sources based on mid-IR color-color selection criteria described.
• Analyze trends in X-ray-optical-infrared color-color diagrams for AGN behavior.
• Study the relationship between optical-near-infrared color and X-ray obscuration in AGN.
• Identify red AGN that are not obscured in X-rays, a finding noted in the description.

Strengths

• Photometry spans a broad wavelength range from U band to 24 microns.
• Catalog includes properties for 409 X-ray sources with a high counterpart identification rate of 401 objects.
• Sources are classified using X-ray and optical criteria to isolate 377 AGN from stars and galaxies.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count is unknown, which may limit suitability assessment.
• Last updated 2026-03-13 17:03:05.400593; freshness should be verified.

Provenance

Source

NASA HEASARC, based on CDS Catalog J/A+A/529/A135.

Collection Method

Likelihood ratio method used to assign optical/IR counterparts to X-ray sources from the XMM-Newton catalog.

Time Range

X-ray observations: April 2000 to December 2002. Optical observations: November 2001 to April 2002 (Subaru) and February 2007 to March 2009 (LBT).

Freshness

Last updated 2026-03-13 17:03:05.400593

Geography

The Lockman Hole, a region of low Galactic extinction.