Astrophysics and Space Science

, Volume 300, Issue 1, pp 45-53

First online:

A Fundamental Plane of Black Hole Activity: Pushing Forward the Unification Scheme

  • Andrea MerloniAffiliated withMax-Planck-Institut für Astrophysik Email author 
  • , Sebastian HeinzAffiliated withCenter for Space Research, MIT
  • , Tiziana Di MatteoAffiliated withMax-Planck-Institut für Astrophysik

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We examine the disc-jet connection in stellar mass and supermassive black holes by investigating the properties of their compact emission in the hard X-ray and radio bands. We compile a sample of ∼100 active galactic nuclei with measured mass, 5 GHz core emission, and 2–10 keV luminosity, together with eight galactic black holes with a total of ∼50 simultaneous observations in the radio and X-ray bands. Using this sample, we study the correlations between the radio (L R) and the X-ray (L X) luminosity and the black hole mass (M). We find that the radio luminosity is correlated with both M and L X, at a highly significant level. We show how this result can be used to extend the standard unification by orientation scheme to encompass unification by mass and accretion rate.


black holes accretion disks jets active galactic nuclei X-ray binaries