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VLA-VIRMOS Deep Field 20-cm Source Catalog

Metadata Updated: September 19, 2025

The authors of this table conducted a deep survey (rms noise ~ 17 microJansky or uJy) with the Very Large Array (VLA) at 1.4 GHz, with a resolution of 6 arcseconds, of a 1 deg<sup>2</sup> region included in the VIRMOS VLT Deep Survey that is centered at RA and Dec (J2000.0) of 02 26 00, -04 30 00, hereafter the VLA-VIRMOS Deep Field, or VLA-VDF. In the same field, they already had multiband photometry down to I<sub>AB</sub> = 25, and spectroscopic observations were to be obtained during the VIRMOS VLT survey. The homogeneous sensitivity over the whole field allowed them to derive a complete sample of 1054 radio sources (5-sigma limit) down to a limit of 0.08 mJy. In their paper, the authors give a detailed description of the data reduction and of the analysis of the radio observations, with particular care to the effects of clean bias and bandwidth smearing, and of the methods used to obtain the catalog of radio sources. To estimate the effect of the resolution bias on their observations, they have modeled the effective angular-size distribution of the sources in their sample and they have used this distribution to simulate a sample of radio sources. Finally, they present the radio count distribution down to 0.08 mJy derived from the catalog. Their counts are in good agreement with the best fit derived from earlier surveys, and are about 50% higher than the counts in the Hubble Deep Field (HDF). The radio count distribution clearly shows, with extremely good statistics, the change in the slope for the sub-mJy radio sources. 19 of the 1054 radio sources were fitted with multiple components. In such cases, the authors list in the catalog an entry for each of the components, identified with a trailing letter (A, B, C or D) in the source name, and an entry for the whole source, identified with a trailing T in the source name. In these cases the total flux was calculated using the task TVSTAT, which allows the integration of the map values over irregular areas, and the sizes are the largest angular sizes. Thus, this catalog contains 1103 entries on 1054 sources, including 49 entries on individual components of composite sources. This table was created by the HEASARC in February 2012 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/403/857">CDS Catalog J/A+A/403/857</a> file catalog.dat. This is a service provided by NASA HEASARC .

Access & Use Information

Public: This dataset is intended for public access and use. License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

Downloads & Resources

Dates

Metadata Created Date April 11, 2025
Metadata Updated Date September 19, 2025

Metadata Source

Harvested from NASA Data.json

Additional Metadata

Resource Type Dataset
Metadata Created Date April 11, 2025
Metadata Updated Date September 19, 2025
Publisher High Energy Astrophysics Science Archive Research Center
Maintainer
Identifier ivo://nasa.heasarc/vvds20cm
Data Last Modified 2025-09-10
Category Astrophysics
Public Access Level public
Bureau Code 026:00
Metadata Context https://project-open-data.cio.gov/v1.1/schema/catalog.jsonld
Schema Version https://project-open-data.cio.gov/v1.1/schema
Catalog Describedby https://project-open-data.cio.gov/v1.1/schema/catalog.json
Harvest Object Id ffc687fe-3823-4e54-af44-2d2e6aab1025
Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
Harvest Source Title NASA Data.json
Homepage URL https://heasarc.gsfc.nasa.gov/W3Browse/all/vvds20cm.html
Program Code 026:000
Source Datajson Identifier True
Source Hash 6bb28f051e7dbb3fbba47df6c9e384d537ea4c1ad94feb0dac6cf0741ba68c22
Source Schema Version 1.1

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