Brownian motion of supermassive black holes in galaxy cores

Research paper by Pierfrancesco Di Cintio, Luca Ciotti, Carlo Nipoti

Indexed on: 11 Aug '20Published on: 12 Aug '19Published in: arXiv - Astrophysics - Astrophysics of Galaxies


We investigate the dynamics of supermassive black holes (SMBHs) in galactic cores by means of a semi-analytic model based on the Langevin equation, including dynamical friction and stochastic noise accounting for the gravitational interactions with stars. The model is validated against direct $N$-body simulations of intermediate-mass black holes in stellar clusters where a realistic number of particles is accessible. For the galactic case, we find that the SMBH experiences a Brownian-like motion with a typical displacement from the geometric center of the Galaxy of a few parsecs, for system parameters compatible with M87. \keywords{stellar dynamics, black hole physics, methods: n-body simulations, methods: statistical.