The VLA-COSMOS Survey. IV. Deep Data and Joint Catalog

TL;DR

This paper presents a deep radio survey of the COSMOS field combining new and existing VLA data, resulting in a comprehensive catalog of faint radio sources with detailed properties and newly identified multi-component sources.

Contribution

It introduces a new deep mosaic and a joint catalog that improves source detection and characterization at low flux levels in the COSMOS field.

Findings

Detected sources down to 4 sigma in the deep mosaic.

Constructed a joint catalog with 43 new multi-component sources.

Provided detailed source properties at high resolution.

Abstract

In the context of the VLA-COSMOS Deep project additional VLA A array observations at 1.4 GHz were obtained for the central degree of the COSMOS field and combined with the existing data from the VLA-COSMOS Large project. A newly constructed Deep mosaic with a resolution of 2.5" was used to search for sources down to 4 sigma with 1 sigma ~ 12 microJy/beam in the central 50'x50'. This new catalog is combined with the catalog from the Large project (obtained at 1.5"x1.4" resolution) to construct a new Joint catalog. All sources listed in the new Joint catalog have peak flux densities of >5 sigma at 1.5" and/or 2.5" resolution to account for the fact that a significant fraction of sources at these low flux levels are expected to be slighty resolved at 1.5" resolution. All properties listed in the Joint catalog such as peak flux density, integrated flux density and source size are determined in the 2.5" resolution Deep image. In addition, the Joint catalog contains 43 newly identified multi-component sources.