Abstract
This paper presents results from our new statistical analysis which is based on unified schemes for the high-power FRII and moderate-power FRI radio sources, and which explores the evolution and Doppler beaming of these sources. The evolution of the ‘parent’, unbeamed, FRI and FRII radio sources is established from radio survey data at 151 MHz, and then extrapolated to high frequency to determine the beaming required to reproduce the 5 GHz source count. This model is used predict the population mix in the 2.7 GHz source count. Comparing the predicted flat-spectrum ‘quasar fraction’ with that found in a large sample of sources selected from the Parkes catalogue indicates good agreement with our unified-scheme prediction. Throughout this paper we use Ω = 1 and h = 0.5.
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Jackson, C.A., Wall, J.V. (1998). Declining Quasar Fractions as Evidence for Unified Schemes. In: Bremer, M.N., Jackson, N., Pérez-Fournon, I. (eds) Observational Cosmology. Astrophysics and Space Science Library, vol 226. Springer, Dordrecht. https://doi.org/10.1007/978-94-011-5238-9_35
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DOI: https://doi.org/10.1007/978-94-011-5238-9_35
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