A numerical study of the continuous beam model of extragalactic radio sources

Several authors have recently proposed that the extended components of extragalactic radio sources must be continuously supplied with energy and/or relativistic particles in a beam emanating from the nuclear regions. This paper reports a numerical study of the dynamics of such a beam in a nonrelativistic, two-fluid approximation. We present results for a variety of beam parameters and include maps of radio surface brightness for comparison with real radio sources. We show that the model does produce radio surface brightness distributions which compare well with observations and show that it is possible to produce both simple, relatively compact sources and sources which have a tail of low surface brightness extending back toward the central galaxy or quasar.