Radio Emission from Galaxies In The Hubble Deep Field

We report on sensitive radio observations made with the VLA at 8.5 GHz, centered on the Hubble Deep Field (HDF). We collected data in the A, CnB, C, DnC, and D configurations, corresponding to angular resolutions ranging from 0.3 to 10. We detected 29 radio sources in a complete sample within 4.6 of the HDF center and above a flux density limit of 9.0 μJy (5 σ). Seven of these sources are located within the HDF itself, while the remaining 22 sources are covered by the Hubble Flanking Fields (HFFs) or ground based optical images. All of the sources in the HDF are identified with galaxies with a mean magnitude R = 21.7, while the mean magnitude of the identifications outside the HDF is R = 22.1. Three radio sources have no optical counterparts to R = 27. Based on a radio and optical positional coincidence, we detected an additional 19 radio sources in this field (seven of which are contained in the HDF) with 6.3 μJy ≤ Sν < 9.0 (3.5 σ ≤ Sν < 5 σ) and R ≤ 25, but which are not included in the complete sample. 1 Based on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc.