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Radio Source Counts at Centimetre Wavelengths

Published online by Cambridge University Press:  07 February 2017

I. I. K. Pauliny-Toth
Affiliation:
Max-Planck-Institut für Radioastronomie, Bonn, F.R.G.
K. I. Kellermann
Affiliation:
National Radio Astronomy Observatory, Green Bank, W.Va. 24944, U.S.A.∗

Abstract

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Counts of radio sources at 5 GHz (6 cm wavelength) have been derived from a number of surveys including a new strong source survey. The source counts do not appear to differ markedly from an integral number-flux relation having a slope of − 1.5 between 5 and 5 × 103 sources per steradian, and show a sharp drop at source densities smaller than 5 sr-1. On the basis of the form of the number counts and the observed anisotropies in the distribution of sources and of their spectra, the cosmological significance of the source counts is questioned. In particular, the evidence for strong cosmic evolution appears weaker than is generally thought unless the cosmological origin of the quasar redshifts is assumed. Measurements of the radio spectra of the sources suggest a dependence of the spectral curvature on flux density.

Type
Part II: The Structure of the Universe
Copyright
Copyright © Reidel 1974 

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