VLACOSMOS - VLA-COSMOS Large Project 1.4-GHz Source Catalog

Overview

The international COSMOS (Cosmic Evolution) survey (Scoville et al. 2007, ApJS, 172, 1) is a panchromatic imaging and spectroscopic survey of a 1.4 degree by 1.4 degree field designed to probe galaxy and SMBH (supermassive black hole) evolution as a function of cosmic environment. One major aspect of the COSMOS survey is the Hubble Space Telescope (HST) Treasury Project (Scoville et al. 2007, ApJS, 172, 38), entailing the largest ever allocation of HST telescope time. The equatorial location of the COSMOS field offers the critical advantage of allowing major observatories from both hemispheres to join forces in this endeavor. State-of-the-art imaging data at all wavelengths (X-ray to centimeter, plus large optical spectroscopic campaigns using the VLT VIMOS and the Magellan IMACS instruments (Lilly et al. 2007; Impey et al. 2007; Trump et al. 2007) have been or are currently being obtained for the COSMOS field. These make the COSMOS field an excellent resource for observational cosmology and galaxy evolution in the important redshift range z ~ 0.5 - 3, a time span covering ~ 75% of the lifetime of the universe.

The VLA-COSMOS Large Project produced a catalog of 3643 radio sources found in the 2 square degrees COSMOS field at 1.4 GHz with a signal-to-noise threshold S/N >= 4.5. The observations in the VLA A and C configurations resulted in a resolution of 1.5" by 1.4" and a mean rms noise of ~ 10.5 µJy (µJy) beam^-1 in the central 1 deg², and of 15 uJy in the 2 deg² field. Eighty radio sources are clearly extended consisting of multiple components, and most of them appear to be double-lobed radio galaxies. The astrometry of the catalog has been thoroughly tested, and the uncertainty in the relative and absolute astrometry are 130 and < 55 mas, respectively.

Catalog Bibcode

2007ApJS..172...46S

References

The VLA-COSMOS Survey. II. Source Catalog of the Large Project
    Schinnerer E., Smolcic V., Carilli C.L., Bondi M., Ciliegi P., Jahnke K.,
    Scoville N.Z., Aussel H., Bertoldi F., Blain A.W., Impey C.D., Koekemoer
    A.M., Le Fevre O., Urry C.M.
   <Astrophys. J. Suppl. Ser., 172, 46-69 (2007)>
   =2007ApJS..172...46S

Provenance

This table was created by the HEASARC in September 2007 based on the electronic version of Table 3 from the reference paper which was obtained from the ApJ web site.

Parameters

Name
The radio source designation using the standard IAU-recommended format with a prefix ('COSMOSVLA'), and the J2000.0 truncated cordinates of the radio source, e.g., 'COSMOSVLA J095738.80+024203.1'. The HEASARC removed a (non-standard) underscore character ('_') between the prefix and the position string which was present in the names as given in the reference paper and the electronic ApJS version of table 3. pa

RA
The Right Ascension of the radio source in the selected equinox. This was given in J2000.0 coordinates to a precision of 0.001 seconds of time in the original table.

Dec
The Declination of the radio source in the selected equinox. This was given in J2000.0 coordinates to a precision of 0.01 arcseconds in the original table.

LII
The Galactic Longitude of the radio source.

BII
The Galactic Latitude of the radio source.

RA_Error
The RMS uncertainty in the Right Ascension of the radio source, in arcseconds.

Dec_Error
The RMS uncertainty in the Declination of the radio source, in arcseconds.

Flux_20_cm
The radio source 1.4-GHz peak (flux density) surface brightness, in mJy/beam. Due to bandwidth smearing effects the peak flux and, hence, the integrated flux for unresolved sources can be underestimated by up to 15% - 20%. A thorough analysis of this will be presented in Bondi et al. (2007, ApJ, submitted).

Flux_20_cm_Error
The RMS uncertainty in the radio Source 1.4-GHz peak flux density, in mJy/beam.

Int_Flux_20_cm
The radio source integrated 1.4-GHz flux density, in mJy. Due to bandwidth smearing effects the peak flux and, hence, the integrated flux for unresolved sources can be underestimated by up to 15% - 20%. A thorough analysis of this will be presented in Bondi et al. (2007, ApJ, submitted).

Int_Flux_20_cm_Error
The RMS uncertainty in the integrated 1.4-GHz flux density of the radio source, in mJy.

RMS_20_cm
The rms measured in the SExtractor noise map at the radio source position, in mJy/beam.

Major_Axis
The deconvolved major axis of the radio source, in arcseconds.

Minor_Axis
The deconvolved minor axis of the radio source, in arcseconds.

Position_Angle
The position angle of the deconvolved major axis of the radio source, in degrees, measured counterclockwise from north.

Resolved_Flag
This flag parameter is set to 'Y' or 'N' depending on whether the source is resolved or unresolved, respectively. In the original table, the corresponding values were 1 and 0.

Sidelobe_Flag
This flag parameter is set to 'Y' or 'N' depending on whether the source may be potentially spurious due to being a sidelobe of a bright source, or not. In the original table, the corresponding values were 1 and 0.

Multi_Component_Flag
This flag parameter is set to 'Y' or 'N' depending on whether the source has multiple or single components, respectively. In the original table, the corresponding values were 1 and 0.

Contact Person

Questions regarding the VLACOSMOS database table can be addressed to the HEASARC Help Desk.

Page Author: Browse Software Development Team
Last Modified: Monday, 16-Sep-2024 17:36:12 EDT