It is proved that the apparent transverse velocities β_(app) and the spectral powers at 10GHz P_(10) of the cores of known superluminal sources are correlated. An interpretation ofthis result within the framework of ...It is proved that the apparent transverse velocities β_(app) and the spectral powers at 10GHz P_(10) of the cores of known superluminal sources are correlated. An interpretation ofthis result within the framework of the relativistic jet model shows that the jet Lorentzfactor γ depends on the intrinsic luminosity of the sources. The probable existence of twosubpopulations of the superluminal sources is shown by a linear regression analysis. 'Small'sources f i.e. the sources without extended emission or with a distance from the core tothe outer edge of the lobe<20 kpc, show lower β_(app) than the 'large' objects; this can beinterpreted as an orientation effect. Since all BL Lac objects belong to the 'small' class,this result sheds new light on such a question as why these sources have lower apparent ve-locities than the 'classical' superluminal quasars.展开更多
基金Supported by the National Natural Science Foundation of China and an honorarium provided by the MPG.
文摘It is proved that the apparent transverse velocities β_(app) and the spectral powers at 10GHz P_(10) of the cores of known superluminal sources are correlated. An interpretation ofthis result within the framework of the relativistic jet model shows that the jet Lorentzfactor γ depends on the intrinsic luminosity of the sources. The probable existence of twosubpopulations of the superluminal sources is shown by a linear regression analysis. 'Small'sources f i.e. the sources without extended emission or with a distance from the core tothe outer edge of the lobe<20 kpc, show lower β_(app) than the 'large' objects; this can beinterpreted as an orientation effect. Since all BL Lac objects belong to the 'small' class,this result sheds new light on such a question as why these sources have lower apparent ve-locities than the 'classical' superluminal quasars.