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arXiv · 2509.13319

Constraints on Dark Matter Structures around Gaia Black Holes

Nuno P. Branco·Ricardo Z. Ferreira·João G. Rosa·Rodrigo Vicente
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Abstract

We demonstrate that Gaia's detection of stars on wide orbits around black holes opens a new observational window on dark matter structures -- such as scalar clouds and dark matter spikes -- predicted in a range of theoretical scenarios. Using precise radial velocity measurements of these systems, we derive state-of-the-art constraints on dark matter density profiles and particle masses in previously unexplored regions of parameter space. We also test the black hole hypothesis against the alternative of a boson star composed of light scalar fields.

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Nuno P. Branco, Ricardo Z. Ferreira, João G. Rosa, Rodrigo Vicente. 2025-09-16. Constraints on Dark Matter Structures around Gaia Black Holes. https://arxiv.org/abs/2509.13319

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