The Jet Power, Radio Loudness, and Black Hole Mass in Radio-loud Active Galactic Nuclei

Jet formation is thought to be closely connected with the mass of the central supermassive black hole in active galactic nuclei. The radio luminosity commonly used in investigating this issue is merely an indirect measure of the energy transported through the jets from the central engine and is severely Doppler boosted in core-dominated radio quasars. In this work, we investigate the relationship between the jet power and the black hole mass, by estimating the jet power using extrapolated extended 151 MHz flux density from the VLA 5 GHz extended radio emission, for a sample of 146 radio-loud quasars compiled from the literature. After removing the effect of relativistic beaming in the radio and optical emission, we find a significant intrinsic correlation between the jet power and the black hole mass. It strongly implies that the jet power, like jet formation, is closely connected with the black hole mass. To eliminate the beaming effect in the conventional radio loudness, we define a new radio loudness as the ratio of the radio extended luminosity to the optical luminosity estimated from the broad-line luminosity. In a tentatively combined sample of radio-quiet with our radio-loud quasars, the apparent gap around the conventional radio loudness R = 10 is not prominent for the new-defined radio loudness. In this combined sample, we find a significant correlation between the black hole mass and new-defined radio loudness.