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Superluminal Motions: The First 100 Sources

  • R. C. Vermeulen
Conference paper
Part of the International Astronomical Union book series (IAUS, volume 175)

Abstract

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. β app in the range 1–5h −1 occur with roughly equal frequency; higher values, up to β app = 10h −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 β app distribution suggests that there might be a skewed distribution of Lorentz factors over the sample, with a peak at γb ≈ 2h −1 and a tail up to at least γb ≈ 10h −1. There appears to be a clearly rising upper envelope to the β app 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.

Keywords

Radio Source Lorentz Factor Apparent Velocity Radio Luminosity Extragalactic Radio Source 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© International Astronomical Union 1996

Authors and Affiliations

  • R. C. Vermeulen
    • 1
  1. 1.California Institute of TechnologyPasadenaUSA

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