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arXiv · 2408.13353

Counter-Rotation and Slow Precession in Aligned Eccentric Nuclear Disks due to Gravitational Wave Recoil Kicks

Jane C. Bright·Tatsuya Akiba·Ann-Marie Madigan
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Abstract

The M31 nucleus contains a supermassive black hole embedded in a massive stellar disk of apsidally-aligned eccentric orbits. It has recently been shown that this disk is slowly precessing at a rate consistent with zero. Here we demonstrate using N-body methods that apsidally-aligned eccentric disks can form with a significant (~0.5) fraction of orbits counter-rotating as the result of a gravitational wave recoil kick of merging supermassive black holes. Higher amplitude kicks map to a larger retrograde fraction in the surrounding stellar population which in turns results in slow precession. We furthermore show that disks with significant counter-rotation are more stable (that is, apsidal-alignment is most pronounced and long lasting), more eccentric, and have the highest rates of stars entering the black hole's tidal disruption radius

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Jane C. Bright, Tatsuya Akiba, Ann-Marie Madigan. 2024-08-23. Counter-Rotation and Slow Precession in Aligned Eccentric Nuclear Disks due to Gravitational Wave Recoil Kicks. https://arxiv.org/abs/2408.13353

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