Deep 3 GHz polarised source counts detect 65 sources (51 deg^{-2}), consistent with 1.4 GHz literature due to spectral index and depolarisation, with a 2σ upper limit of <2.0 deg^{-2} on polarised SFG density.
Sample variance, source clustering and their influence on the counts of faint radio sources
3 Pith papers cite this work. Polarity classification is still indexing.
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Pith papers citing it
abstract
The shape of the curves defined by the counts of radio sources per unit area as a function of their flux density was one of the earliest cosmological probes. Radio source counts continue to be an area of interest, used to study the relative populations of galaxy types in the Universe (as well as investigate any cosmological evolution in luminosity functions). They are a vital consideration for determining how source confusion may limit the depth of a radio interferometer observation, and are essential for characterising extragalactic foregrounds in CMB experiments. There is currently no consensus as to the relative populations of the faintest (sub-mJy) source types, where the counts turn-up. Most of the source counts in this regime are gathered from multiple observations that each use a deep, single pointing with a radio interferometer. These independent measurements show large amounts of scatter (factors ~ a few) that significantly exceeds their stated uncertainties. In this article we use a simulation of the extragalactic radio continuum emission to assess the level at which sample variance may be the cause of the scatter. We find that the scatter induced by sample variance in the simulated counts decreases towards lower flux density bins as the raw source counts increase. The field-to-field variations are significant, and could even be the sole cause at >100 {\mu}Jy. We present a method for evaluating the flux density limit that a survey must reach in order to reduce the count uncertainty induced by sample variance to a specific value. We also derive a method for correcting Poisson errors on counts in order to include the uncertainties due to the cosmological clustering of sources. An empirical constraint on the effect of sample variance at these low luminosities is unlikely to arise until the completion of new large-scale surveys with next-generation radio telescopes.
years
2026 3verdicts
UNVERDICTED 3representative citing papers
Including radiative losses in analytic models of high-redshift radio galaxies reduces predicted radio and X-ray luminosities compared to models that neglect them.
First measurement of angular clustering w(theta) for radio sources at 816 MHz over 800 deg2 yields positive signal and effective bias 1.53-2.0 depending on N(z) prior.
citing papers explorer
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The VLA-COSMOS 3 GHz Large Project: Polarised source counts and catalogue
Deep 3 GHz polarised source counts detect 65 sources (51 deg^{-2}), consistent with 1.4 GHz literature due to spectral index and depolarisation, with a 2σ upper limit of <2.0 deg^{-2} on polarised SFG density.
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A simulation-based analytic model of radio galaxies II: self-consistent radiative losses
Including radiative losses in analytic models of high-redshift radio galaxies reduces predicted radio and X-ray luminosities compared to models that neglect them.
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Tracing Large-scale Structure with the MeerKLASS On-the-Fly Survey: Angular Clustering of Radio Sources at 816 MHz
First measurement of angular clustering w(theta) for radio sources at 816 MHz over 800 deg2 yields positive signal and effective bias 1.53-2.0 depending on N(z) prior.