GMRT Field I 150-MHz Radio Source Catalog for Epoch of Reionization Studies

150-MHz observations from the Giant Metrewave Radio Telescope characterize foregrounds for detecting the redshifted 21-cm signal from the Epoch of Reionization. The catalog for the most sensitive field (Field I) contains sources to a limiting flux of 9 mJy, with an rms noise of 1.3 mJy beam⁻¹. NASA HEASARC created this table in September 2013 based on data from a 9.8-hour observation made on 2008 January 8.

Use Cases

• Benchmarking foreground removal techniques based on the 1.5% residual artefact level for the brightest source.
• Modeling the radio source population based on the differential source count power law slope of -1.6.
• Studying the properties of classical radio-loud active galactic nuclei based on the lack of source count flattening at lower flux densities.
• Assessing point source subtraction efficacy in high Galactic latitude fields.

Strengths

• Catalog is derived from a 9.8-hour observation with a low rms noise of 1.3 mJy beam⁻¹.
• Residual artefacts for the brightest source are quantified at less than 1.5% in the most sensitive field.
• Differential source counts are characterized with a specific power law slope of -1.6.

Limitations

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

Provenance

Source

National Aeronautics and Space Administration (NASA HEASARC), based on CDS Catalog J/MNRAS/426/3295.

Collection Method

Observational data from the Giant Metrewave Radio Telescope (GMRT) Time Allocation Committee cycles.

Time Range

Primary observation for Field I was made on 2008 January 8.

Freshness

Last updated 2026-03-13 18:24:14.896002; freshness should be verified.

Geography

Field I is centered on J2000.0 RA 5h 30m 00s, Dec +60° 00' 00", at high Galactic latitude (b > 10°).