CRATES: Combined Radio All-Sky Targeted Eight-GHz Survey of 11,000 Sources

11,131 bright, flat-spectrum radio sources were cataloged in the CRATES survey, which provides precise positions and spectral indices. The catalog was assembled by NASA HEASARC in 2007 from existing observations, new data, and reprocessed archival VLA and ATCA data. It contains 14,467 entries, including 762 non-detections, due to multiple 8.4-GHz counterparts for single 4.8-GHz sources.

Use Cases

• Identifying high-energy blazar candidates based on flat-spectrum radio properties.
• Comparing source structures and spectral indices with other high-frequency radio surveys.
• Studying the morphology of extragalactic radio sources using subarcsecond resolution data.

Strengths

• Catalog contains precise positions and spectral indices for approximately 11,000 sources.
• Provides nearly uniform extragalactic sky coverage for sources brighter than 65 mJy at 4.8 GHz.
• Combines data from multiple established surveys (CLASS, PMN-CA) with new and reprocessed observations.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count is unknown, which may limit suitability assessment.
• Last updated 2026-03-13 16:44:47.421639; freshness should be verified.

Provenance

Source

NASA HEASARC, based on electronic version from the ApJ web site.

Collection Method

Assembled from existing surveys (CLASS, PMN-CA), reprocessed archival VLA/ATCA data, and new observations to fill gaps.

Freshness

Catalog created in August 2007; last metadata update 2026-03-13.

Geography

Nearly uniform extragalactic sky coverage (|b| > 10 degrees).