Swift XRT Counterparts to Unidentified Fermi Gamma-Ray Sources

267 Swift XRT X-ray sources detected within the fields of view of 112 unidentified gamma-ray sources from the 1FGL catalog. The data includes positions and 0.3-10 keV count rates for sources with a signal-to-noise ratio of 3 or more, derived from archival analysis of 134 high-latitude sources. This table was created by NASA HEASARC in September 2014 based on a reference paper in the Astrophysical Journal Supplement.

Use Cases

• Cross-matching X-ray and gamma-ray sources based on positional data and error ellipses.
• Analyzing spectral energy distributions (SEDs) from radio to gamma-rays for anomalous objects.
• Identifying unique astronomical objects based on X-ray detection criteria and signal-to-noise ratios.
• Studying the population of unidentified high Galactic latitude gamma-ray sources observed by Swift/XRT.

Strengths

• Focuses on 134 high-latitude unidentified gamma-ray sources from a well-defined catalog.
• Provides data for 267 X-ray sources with a defined signal-to-noise threshold of 3 or more.
• Includes positional data and 0.3-10 keV count rates for cross-reference with gamma-ray error ellipses.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count is unknown, which may limit suitability assessment.
• Data is based on observations made public by October 2011; newer catalogs may exist.

Provenance

Source

NASA HEASARC, based on Table 4 from a reference paper in the Astrophysical Journal Supplement.

Collection Method

Analysis of archival X-ray data from Swift/XRT for Fermi/LAT 1FGL catalog sources meeting specific selection criteria.

Freshness

Last updated 2026-03-13 18:38:22.091689; freshness should be verified.

Geography

High Galactic latitude (|b| > 10 degrees).