The ratio R_T of the jet to the unbeamed luminosities for superluminal radio sources

Relativistic beaming model has been successfully used to explain the observational properties in active galactic nuclei. In this model the emissions are composed of two components, i.e. the boosted and the isotropic emissions. But how much is from each part is unknown. It has been assumed that the luminosity in the jet is proportional to the unbeamed in the comoving frame. However, the value of this ratio is not easy to determine. In this paper, we use the beaming model and the radio sources with superluminal motions to estimate the ratio, R_T, for each source. We find R_T= 0.044±0.02, which is consistent with that found by Orr and Browne.