Abstract
We present a kinematic model for asymmetries in radio sources, which enabled an estimation of the projected hotspot/lobe advance speed for high-luminosity radio sources using the arm-length ratio (Q) and apparent flux ratio (R). We obtain a mean projected speed along the line of sight </line{beta}> = 0.15±0.05 for all the sources in our sample, using the Q parameter and </line{beta}> ∼0.12-0.32 for rho=2alpha+1 (where rho is the electron energy spectrum index) using the R parameter. Our results indicate that the adopted model of brightness evolution of plasma element affects the values of projected speed. Regression analyses indicate that the estimated speeds using the Q and R parameters show some correlation with distance (L) and luminosity (P), especially for quasars.
