Published online by Cambridge University Press: 12 April 2016
In mergers of galaxies their central black holes are accumulated together. We show that few-black hole systems arise which decay through black hole collisions and black hole ejections. The ejection statistics are calculated and compared with two observed systems where ejections have been previously suggested: double radio sources and high redshift quasars near low redshift galaxies. In both cases certain aspects of the associations are explained by the merger hypothesis.