EVOLUTIONARY TRACKS OF FRII SOURCES THROUGH THE P-D DIAGRAM

This is the second in a series of papers presenting an analytical mode l for the evolution of FRII radio sources. In this paper we evaluate t he expected radio emission from a radio source incorporating energy-lo ss processes for the relativistic electrons. By combining these result s with our earlier dynamical model we calculate evolutionary tracks th rough the power-linear size diagram. These tracks are in good agreemen t with the observed distribution of sources in this diagram. The effec ts of different forms for the evolution of the magnetic held in the co coon, the redshift of the source, the environment of the source, and t he defining parameters of the jet are investigated. The evolutionary t racks are found to be insensitive to the assumed form of the magnetic held evolution. Some evidence against protons as a major constituent o f the jet material is also found.