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arXiv · 1908.04283

Brownian motion of supermassive black holes in galaxy cores

Pierfrancesco Di Cintio·Luca Ciotti·Carlo Nipoti
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Abstract

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.

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Pierfrancesco Di Cintio, Luca Ciotti, Carlo Nipoti. 2019-08-12. Brownian motion of supermassive black holes in galaxy cores. https://doi.org/10.1017/s1743921319007221

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