The ATLAS 9.0 GHz Survey of the Extended Chandra Deep Field South: The Faint 9.0 GHz Radio Population

Abstract

We present a new image of the 9.0 GHz radio emission from the extended Chandra Deep Field South. A total of 181 hours of integration with the Australia Telescope Compact Array has resulted in a 0.276 square degree image with a median sensitivity of $\sim$20 $\mu$Jy/beam rms, for a synthesised beam of 4.0 $\times$ 1.3 arcsec. We present a catalogue of the 9.0 GHz radio sources, identifying 70 source components and 55 individual radio galaxies. Source counts derived from this sample are consistent with those reported in the literature. The observed source counts are also generally consistent with the source counts from simulations of the faint radio population. Using the wealth of multiwavelength data available for this region, we classify the faint 9 GHz population and find that 91% are radio loud AGN, 7% are radio quiet AGN and 2% are star forming galaxies. The 9.0 GHz radio sources were matched to 5.5 and 1.4 GHz sources in the literature and we find a significant fraction of flat or inverted spectrum sources, with 36% of the 9 GHz sources having ${\alpha }_{5.5GHz}^{9.0GHz}$ $>$ -0.3 (for $S\propto {\nu }^{\alpha }$). This flat or inverted population is not well reproduced by current simulations of radio source populations.

17 pages, 12 figures. Accepted for publication in MNRAS

References in corpus (15)

• 3D-HST WFC3-selected Photometric Catalogs in the Five CANDELS/3D-HST Fields: Photometry, Photometric Redshifts and Stellar Masses
• The Chandra Deep Field-South Survey: 7 Ms Source Catalogs
• The 0.4 < z < 1.3 star formation history of the Universe as viewed in the far-infrared
• Deep ATLAS radio observations of the CDFS-SWIRE field
• The Star Formation History of the Universe as Revealed by Deep Radio Observations
• A new method to separate star forming from AGN galaxies at intermediate redshift: The submillijansky radio population in the VLA-COSMOS survey
• An ALMA survey of submillimetre galaxies in the Extended Chandra Deep Field South: Spectroscopic redshifts
• OzDES multifibre spectroscopy for the Dark Energy Survey: Three year results and first data release
• The Australia Telescope 20 GHz (AT20G) Survey: The Bright Source Sample
• Extragalactic Radio Continuum Surveys and the Transformation of Radio Astronomy
• The ATESP 5 GHz radio survey I. Source counts and spectral index properties of the faint radio population
• Calibration update of the COMBO-17 CDFS catalogue
• ATLAS 1.4 GHz Data Release 2 -- I. Observations of the CDF-S and ELAIS-S1 fields and methods for constructing differential number counts
• The faint source population at 15.7 GHz - I. The radio properties
• Sub-millimetre source identifications and the micro-Jansky source population at 8.4 GHz in the William Herschel Deep Field

Cited by in corpus (6)

• Remnant Radio Galaxies Discovered in a Multi-frequency Survey
• The MAVERIC Survey: Radio catalogs and source counts from deep Very Large Array imaging of 25 Galactic globular clusters
• The cosmic radio background from 150 MHz--8.4 GHz, and its division into AGN and star-forming galaxy flux
• The VLA Frontier Fields Survey: Deep, High-resolution Radio Imaging of the MACS Lensing Clusters at 3 and 6 GHz
• Selecting and Modelling Remnant AGNs with Limited Spectral Coverage
• Properties of Polarized Radio Sources in the Wide Chandra Deep Field South from 2 to 4GHz