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arXiv · 1812.07053

Vector Resonant Relaxation of Stars around a Massive Black Hole

Jean-Baptiste Fouvry·Ben Bar-Or·Pierre-Henri Chavanis
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Abstract

In the vicinity of a massive black hole, stars move on precessing Keplerian orbits. The mutual stochastic gravitational torques between the stellar orbits drive a rapid reorientation of their orbital planes, through a process called vector resonant relaxation. We derive, from first principles, the correlation of the potential fluctuations in such a system, and the statistical properties of random walks undergone by the stellar orbital orientations. We compare this new analytical approach with effective $N$-body simulations. We also provide a simple scheme to generate the random walk of a test star's orbital orientation using a stochastic equation of motion. We finally present quantitative estimations of this process for a nuclear stellar cluster such as the one of the Milky Way.

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Jean-Baptiste Fouvry, Ben Bar-Or, Pierre-Henri Chavanis. 2018-12-17. Vector Resonant Relaxation of Stars around a Massive Black Hole. https://doi.org/10.3847/1538-4357/ab2f78

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