Galactic Center Chandra X-Ray Catalog: 9,017 Sources

9,017 X-ray point sources were identified in Chandra ACIS-I observations totaling 2.25 Ms of exposure around the Galactic center, doubling the known sources in the region. The catalog, created by NASA HEASARC in 2009, includes sources detected as of August 2007, with 60% having positions accurate to <1 arcsecond. It is designed to be inclusive, containing sources of varying quality, including 134 with net counts consistent with zero at 90% confidence.

Use Cases

• Identifying variable X-ray sources based on the reported 3% intra-observation and 10% inter-observation flux variations.
• Studying the spatial distribution of X-ray sources relative to stellar models, particularly around star clusters like the Arches and Quintuplet.
• Investigating periodic signals in X-ray sources, such as the 1745-second periodic signal found in CXOUGC J174622.7-285218.
• Analyzing source luminosity distributions, which are noted to be flatter near specific star-forming regions.
• Cataloging faint or marginal sources, including those detected in a single energy band or with transient behavior.

Strengths

• Large catalog of 9,017 sources, increasing known X-ray sources in the region by a factor of 2.5.
• High positional accuracy for 60% of sources (<1 arcsecond) and 20% (<0.5 arcsecond) at 95% confidence.
• Deep exposure of 2.25 Ms, with sensitivity to luminosities of 4e32 erg/s over 1 square degree at 8 kpc.
• Inclusive design that documents sources of questionable quality, providing a complete observational record.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count is unknown, which may limit suitability assessment.
• The catalog incorporates observations only as of August 2007; newer data is not included.

Provenance

Source

National Aeronautics and Space Administration (NASA) via HEASARC.

Collection Method

Compiled from Chandra ACIS-I observations, superseding previous HEASARC tables CHANGALCEN and CHANC150PC.

Time Range

Observations as of August 2007.

Freshness

Last updated 2026-03-13 20:12:08.254004; freshness should be verified.

Geography

Covers a 2° by 0.8° field around the Galactic center.