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Superluminal motions: the first 100 sources

Published online by Cambridge University Press:  25 May 2016

R.C. Vermeulen*
Affiliation:
California Institute of Technology, Astronomy 105–24, Pasadena, CA 91125, USA

Abstract

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First results from a large homogeneous superluminal motion survey are presented. The data do not show compelling evidence for the existence of intrinsically different populations of galaxies, BL Lac objects, or quasars. βapp in the range 1–5 h–1 occur with roughly equal frequency; higher values, up to βapp = 10 h–1, are rather more scarce than appeared to be the case from earlier work, which evidently concentrated on sources which are not representative of the general population. The βapp distribution suggests that there might be a skewed distribution of Lorentz factors over the sample, with a peak at γb ≈ 2 h–1 and a tail up to at least γb ≈ 10 h–1. There appears to be a clearly rising upper envelope to the βapp distribution when plotted as a function of observed 5 GHz luminosity; a combination of source counts and the apparent velocity statistics in a larger sample could provide much insight into the properties of radio jet sources.

Type
Properties of Radio Sources
Copyright
Copyright © Kluwer 1996 

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