Evolution of Radio Source Components and the Quasar/Galaxy Unification Scheme

Abstract

In this work, a theoretical model is developed for explanation of temporal evolution of extragalactic radio sources via beaming, orientation effects and asymmetries. Equation of the form D≈P±q1+z−m is used to account for the D ∼ P/z relation. Also, D≈D01+z−1+z1+z2 accounted properly for Ω0=1 cosmology than the Ω0=0 counterpart in linear size versus redshift of radio sources. Similarly, D=Dc1∓lnPPc1/2 model explained redshift-luminosity relationship of extragalactic radio sources. The results from the regression analyses are q = +0.003 (r = 0.04) for sources with z < 1 and q = −1.59 (r = −0.6) for all z≥1 sources. A critical linear size, Dc of 316kpc which matches the maximum theoretical linear size, Dmax of 0.15D0 at a critical redshift zc∼1 and a critical luminosity Pc=26.33WHz−1 are obtained. The indication of all these results is that the linear size of radio sources evolves up to a certain limit in D–P plane and thereafter decreases with increasing luminosity as predicted in this work.