Long-term evolution of massive black hole binaries. IV. Mergers of galaxies with collisionally relaxed nuclei

Understand

We simulate mergers between galaxies containing collisionally-relaxed nuclei around massive black holes (MBHs).

• Our galaxies contain four mass groups, representative of old stellar populations; a primary goal is to understand the distribution of stellar-mass black holes (BHs) after the merger.
• Mergers are followed using direct-summation N-body simulations, assuming a mass ratio of 1:3 and two different orbits.
• Evolution of the binary MBH is followed until its separation has shrunk by a factor of 20 below the hard-binary separation.