The Kinetic Luminosity Function and the Jet Production Efficiency of Growing Black Holes

Abstract

We derive the kinetic luminosity function for flat-spectrum radio jets, using the empirical and theoretical scaling relation between jet power and radio core luminosity. The normalization for this relation is derived from a sample of flat-spectrum cores in galaxy clusters with jet-driven X-ray cavities. The total integrated jet power at z = 0 is Wtot ≈ 3 × 10 40 ergs s-1 Mpc-3. By integrating W tot over redshift, we determine the total energy density deposited by jets as etot ≈ 2 × 1058 ergs Mpc-3. Both Wtot and etot are dominated by low-luminosity sources. Comparing etot to the local black hole mass density ρBH gives an average jet production efficiency of εtot = ejet/ρBHc2 ≈ 3%. Since black hole mass is accreted mainly during high-luminosity states, εjet is likely much higher during low-luminosity states. © 2007. The American Astronomical Society. All rights reserved.