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arXiv · 2411.18601

Gravitational atoms beyond the test field limit: The case of Sgr A* and ultralight dark matter

Miguel Alcubierre·Juan Barranco·Argelia Bernal·Juan Carlos Degollado·Alberto Diez-Tejedor·Miguel Megevand·Darío Núñez·Olivier Sarbach
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Abstract

We construct gravitational atoms including self-gravity, obtaining solutions of the Einstein-Klein-Gordon equations for a scalar field surrounding a non-rotating black hole in a quasi-stationary approximation. We resolve the region near the horizon as well as the far field region. Our results are relevant in a wide range of masses, from ultralight to MeV scalar fields and for black holes ranging from primordial to supermassive. For instance, a system with a scalar field consistent with ultralight dark matter and a black hole mass comparable to that of Sagittarius A* can be modeled. A density spike near the event horizon, although present, is negligible, contrasting with the prediction in [P. Gondolo and Silk, Phys. Rev. Lett., 83:1719-1722, 1999] for cold dark matter.

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Miguel Alcubierre, Juan Barranco, Argelia Bernal, Juan Carlos Degollado, Alberto Diez-Tejedor, Miguel Megevand, Darío Núñez, Olivier Sarbach. 2024-11-27. Gravitational atoms beyond the test field limit: The case of Sgr A* and ultralight dark matter. https://doi.org/10.1088/1361-6382%2Fae110a

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