Beaming and precession in the inner jet of 3C 273

Abstract

The quasar 3C 273 is a well-known superluminal source. More than 10 radio components have been detected moving away from the nucleus with different superluminal speeds and position angles. The pattern of ejection suggests the existence of a precessing inner jet, whose kinematics has been discussed by Abraham & Romero (1999). We now present a binary black hole model for the central engine of 3C 273 where the rapid precession is tidally induced in the primary accretion disk inner region by a secondary black hole in a non-coplanar orbit. Using γ- and X-ray data we estimate upper limits for the mass of the primary, and then we compute the relevant parameters of the system for a variety of disk models. We also discuss some of the implications of the model for the electromagnetic and gravitational radiation from 3C 273.