GMRT J0916+6348 Field: 317 Radio Sources with Multi-Frequency Spectra

374 radio sources were observed in a deep field search for fossil radio lobes, with 317 sources detected at a minimum of three frequencies. The catalog, created by NASA HEASARC in March 2012, is based on Giant Metrewave Radio Telescope observations from 2005 and 2008. Almost all sources show a straight spectrum with a median spectral index of ~0.8, and 14 sources were identified with very steep spectra (alpha >~ 1.3).

Use Cases

• Identifying candidate fossil radio lobes and episodic activity based on spectral steepness.
• Analyzing the distribution of spectral indices for a population of radio sources.
• Cross-matching radio source catalogs using data from GMRT, WENSS, NVSS, and FIRST surveys.
• Studying the prevalence of very-steep-spectrum sources (alpha >~ 1.3) in deep low-frequency observations.

Strengths

• Includes 317 radio sources with measurements at a minimum of 3 frequencies out of 6 utilized.
• Combines deep GMRT observations with data from three major sky surveys (WENSS, NVSS, FIRST).
• Provides derived spectral index values, identifying 14 very-steep-spectrum sources.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count for the full initial detection list (374) is known, but the exact row count for the provided 317-source table is unspecified.
• Data may reflect observational bias inherent to the specific GMRT field centered on J0916+6348.

Provenance

Source

NASA HEASARC, based on CDS Catalog J/MNRAS/392/1403.

Collection Method

Observations from the Giant Metrewave Radio Telescope (GMRT) at 153, 244, 610, and 1260 MHz, combined with archival survey data.

Time Range

Observations from 2005-11-26, 2005-12-12, and 2008-04-22.

Freshness

Last updated 2026-03-13 16:57:08.342544; freshness should be verified.

Geography

Field centered on celestial coordinates J0916+6348.