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arXiv · 2410.04175

Einstein Cluster as Central Spiky Distribution of Galactic Dark Matter

Kei-ichi Maeda·Vitor Cardoso·Anzhong Wang
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Abstract

Using the Einstein cluster models, we construct a fully relativistic, spherically symmetric, spiky structure of matter distribution near a supermassive black hole. We introduce and discuss three simple toy models, together with a more realistic model, which includes a Hernquist-type distribution with a typical galaxy scale. We find that the innermost stable circular orbit (ISCO) depends on the details of the environment, and lies between the photon radius (at $3M_{\rm BH}$) and the ISCO radius of an isolated black hole of mass $M_{\rm BH}$ (at $6M_{\rm BH}$).

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Kei-ichi Maeda, Vitor Cardoso, Anzhong Wang. 2024-10-05. Einstein Cluster as Central Spiky Distribution of Galactic Dark Matter. https://arxiv.org/abs/2410.04175

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