Revisiting the Fundamental Planes of Black Hole Activity for Strong Jet Sources

Abstract

Whether the X-ray emissions of strong jet sources originate from disk+coronas or jets is still controversial. In this work, we constructed a strong jet sample containing 50 flat-spectrum radio quasars, 51 low-synchrotron-peaked BL Lac objects, and 18 intermediate-synchrotron-peaked BL Lac objects to explore the origin of X-ray emissions. Generally, blazars are the typical radio-loud active galactic nucleus with a powerful jet toward the observer, causing their broadband emissions to be boosted. By considering the Doppler boosting effect, we obtain the intrinsic radio–X-ray correlation and the fundamental plane (FP) of black hole activity for the strong jet sources: the intrinsic radio–X-ray correlation is ${L}_{{\rm{R,int}}}\propto {L}_{{\rm{X,int}}}^{1.04}$ , which favor the jet-dominated mode; the intrinsic FP is ${\rm{log}}\,{L}_{{\rm{R}},{\rm{int}}}=(1.07\pm 0.06)\,{\rm{log}}\,{L}_{{\rm{X}},{\rm{int}}}$ $-(0.22\pm 0.10)\,{\rm{log}}\,{M}_{{\rm{BH}}}-(3.77\pm 2.11)$ , which can be interpreted by the hybrid mode of jet+standard disk. Our results suggest that the X-ray emissions of strong jet sources are dominated by the jets, but there may also be a small contribution from the disk. In addition, the radio–X-ray correlation and FP of strong jet sources do not have a significant dependence on the Eddington-ratio.

Keywords

• Accretion
• Galaxy accretion disks
• Black hole physics
• Active galactic nuclei
• Radio jets
• X-ray astronomy