CLANS: Optical and Infrared Catalog for Chandra X-ray Sources

The Chandra Lockman Area North Survey (CLANS) catalog contains redshift and photometric data for X-ray sources. It was created by NASA HEASARC in December 2008 based on data from the Astrophysical Journal. The survey bridges the gap between ultra-deep and shallow, large-area X-ray surveys, probing sources that contribute to the 2-8 keV X-ray background.

Use Cases

• Analyzing the effect of spectral type on X-ray luminosity function evolution based on survey data.
• Comparing optical spectral types with X-ray spectral properties as described in the OPTX Project.
• Studying the population of X-ray sources in the flux range of the observed break in the log N - log S distribution.
• Extending redshift information for X-ray source samples using photometric redshift techniques.

Strengths

• Redshifts for the CLANS field are described as all new.
• For fluxes above 10^-14 ergs cm^-2 s^-1 (2-8 keV), the authors report redshifts for 76% of sources across the CLANS, CLASXS, and CDF-N surveys.
• The survey is described as one of the most spectroscopically complete to date.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count is unknown, which may limit suitability assessment.
• Description metadata is limited; actual data quality requires manual inspection after download.

Provenance

Source

National Aeronautics and Space Administration (NASA HEASARC)

Collection Method

Created based on an electronic version of a table from a paper obtained from the Astrophysical Journal website.

Freshness

Last updated 2026-03-13 17:00:08.901957; freshness should be verified.