On the counting of radio sources in the steady-state

Abstract

The problem of the number count of radio sources as a function of the incident flux is shown to depend on two crucial features: (i) the size and behaviour of condensations (ii) the dependence on age of the probabillty of a galaxy being a radio source. Provided the probability rises by a factor 102 for galaxies with ages from H-1 to about -1, and provided the primary condensations of the steady-state theory possess initial dimensions of order 30 megaparsecs, the radio source count can rise more steeply than is the case for sources umformly distributed in Euclidean space. Each primary condensation contains of the order of io galaxies, which in the main expand apart from each other as the universe expands. It is shown that a luminosity function can be chosen for the radio sources giving results consistent with observation, not only for the source count, but also with the data on angular diameters and with experience in the problem of optical identifications.