Abstract

We consider the consequences of gravitational wave recoil for unified models of active galactic nuclei (AGN).  Spatial oscillations of supermassive black holes (SMBHs) about the cores of galaxies following gravitational wave (GW) recoil imply that the SMBHs spend a significant fraction of time off-nucleus, at scales beyond that of the molecular obscuring torus.  Assuming reasonable distributions of recoil velocities, we compute the off-core timescale of (intrinsically type-2) quasars.  We find that roughly one-half of major mergers result in a SMBH being displaced beyond the torus for a time of 107.5 yr or more, comparable to quasar activity time scales.  Since major mergers are most strongly affected by GW recoil, our results imply a deficiency of type 2 quasars  in comparison to Seyfert 2 galaxies.  Other consequences of the recoil oscillations for the observable properties of AGN are also discussed.