10C continued: a deeper radio survey at 15.7 GHz

Abstract

We present deep 15.7-GHz observations made with the Arcminute Microkelvin Imager Large Array in two fields previously observed as part of the Tenth Cambridge (10C) survey. These observations allow the source counts to be calculated down to 0.1 mJy, a factor of five deeper than achieved by the 10C survey. The new source counts are consistent with the extrapolated fit to the 10C source count, and display no evidence for either steepening or flattening of the counts. There is thus no evidence for the emergence of a significant new population of sources (e.g. starforming) at 15.7 GHz flux densities above 0.1 mJy, the flux density level at which we expect starforming galaxies to begin to contribute. Comparisons with the de Zotti et al. model and the SKADS Simulated Sky show that they both underestimate the observed number of sources by a factor of two at this flux density level. We suggest that this is due to the flat-spectrum cores of radio galaxies contributing more significantly to the counts than predicted by the models.

arXiv comment11 pages, 11 figures. Accepted for publication in MNRAS

References in corpus (20)

• A semi-empirical simulation of the extragalactic radio continuum sky for next generation radio telescopes
• Radio and Millimeter Continuum Surveys and their Astrophysical Implications
• Predictions for high-frequency radio surveys of extragalactic sources
• Extragalactic Source Counts and Contributions to the Anisotropies of the Cosmic Microwave Background. Predictions for the Planck Surveyor mission
• The Arcminute Microkelvin Imager
• Extragalactic radio source evolution under the dual-population unification scheme
• High--frequency predictions for number counts and spectral properties of extragalactic radio sources. New evidences of a break at mm wavelengths in spectra of bright blazar sources
• Radio imaging of the Subaru/XMM-Newton Deep Field - III. Evolution of the radio luminosity function beyond z=1
• 9C: A Survey of Radio Sources at 15 GHz with the Ryle Telescope
• The Australia Telescope 20GHz (AT20G) Survey: analysis of the extragalactic source sample
• An infrared-radio simulation of the extragalactic sky: from the Square Kilometer Array to Herschel
• Sample variance, source clustering and their influence on the counts of faint radio sources
• 10C Survey of Radio Sources at 15.7 GHz: I - Observing, mapping and source extraction
• 10C Survey of Radio Sources at 15.7 GHz: II - First Results
• Galaxy and Mass Assembly (GAMA): The evolution of bias in the radio source population to z ~ 1.5
• The faint source population at 15.7 GHz - I. The radio properties
• 9C continued: a radio-source survey at 15 GHz
• Deep 20-GHz survey of the Chandra Deep Field South and SDSS Stripe 82: source catalogue and spectral properties
• The faint radio source population at 15.7 GHz - II. Multi-wavelength properties
• The host galaxies of micro-Jansky radio sources

Cited by in corpus (16)

• The faint radio sky: radio astronomy becomes mainstream
• The LOFAR window on star-forming galaxies and AGN - curved radio SEDs and IR-radio correlation at $0<z<2.5$
• The Tiered Radio Extragalactic Continuum Simulation (T-RECS)
• Galaxy Evolution in the Radio Band: The Role of Starforming Galaxies and Active Galactic Nuclei
• A Digital Correlator Upgrade for the Arcminute MicroKelvin Imager
• The prevalence of core emission in faint radio galaxies in the SKA Simulated Skies
• Linear radio size evolution of $\mu$Jy populations
• The Tiered Radio Extragalactic Continuum (T-RECS) simulation II: HI emission and continuum-HI cross-correlation
• The ATLAS 9.0 GHz Survey of the Extended Chandra Deep Field South: The Faint 9.0 GHz Radio Population
• GMRT 610-MHz observations of the faint radio source population - and what these tell us about the higher-radio-frequency sky
• The faint radio source population at 15.7 GHz -- IV. The dominance of core emission in faint radio galaxies
• Modelling radio luminosity functions of radio-loud AGN by the cosmological evolution of supermassive black holes
• AMI-LA Observations of the SuperCLASS Super-cluster
• ATCA detections of massive molecular gas reservoirs in dusty, high-z radio galaxies
• Artificial Broadcasts as Galactic Populations: III. Constraints on Radio Broadcasts from the Cosmic Population of Inhabited Galaxies
• An empirical model of the extragalactic radio background