Radio Source Evolution & Unified Schemes

C.A. Jackson, PASA, 16 (2), 124
The html and gzipped postscript versions of this paper are in preprint form.
To access the final published version, download the pdf file
.

Next Section: Extragalactic radio sources: What
Contents Page: Volume 16, Number 2

Radio Source Evolution & Unified Schemes

C A Jackson1

Department of Astrophysics, School of Physics, University of Sydney, NSW 2006
cjackson@physics.usyd.edu.au

Abstract:

Powerful extragalactic radio sources are characterised by kpc-scale synchrotron emission associated with highly-collimated outflows of relativistic plasma. It is hypothesized that this outflowing plasma is powered by accretion processes concomitant with a central massive black hole. The radio morphologies of these sources comprise jets, lobes and for the most powerful sources, hotspots. At first sight, powerful extragalactic radio sources are a mixed group of objects, with the result that only some gross property delineates them further (e.g. steep-spectrum or flat-spectrum). However, there is accumulating observational evidence which suggests that it is the orientation of the radio axis to our line-of-sight which dictates their observed characteristics. This orientation-dependence has been incorporated into `unified schemes', which physically-link apparently disparate radio source types via the random orientation of a `parent' population on the plane of the sky. This paper summarises the `dual-population unified scheme' paradigm investigated by and discusses some of its implications with respect to radio source cosmology.

Keywords:galaxies:evolution, galaxies:jets, quasars:general, radio continuum:galaxies





Welcome... About Electronic PASA... Instructions to Authors
ASA Home Page... CSIRO Publishing PASA
Browse Articles HOME Search Articles
© Copyright Astronomical Society of Australia 1997
ASKAP
Public