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arXiv · 2408.16020

Galactic black hole immersed in a dark halo with its surrounding thin accretion disk

Mohaddese Heydari-Fard·Malihe Heydari-Fard·Nematollah Riazi
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Abstract

By considering the analytic, static and spherically symmetric solution for the Schwarzschild black holes immersed in dark matter fluid with non-zero tangential pressure \cite{Jusufi:2022jxu} and Hernquist-type density profiles \cite{Cardoso}, we compute the luminosity of accretion disk. We study the circular motion of test particles in accretion disk and calculate the radius of the innermost stable circular orbits. Using the steady-state Novikov-Thorne model we also compute the observational characteristics of such black hole's accretion disk and compare our results with the usual Schwarzschild black hole in the absence of dark matter fluid. We find that the tangential pressure plays a significant role in decreasing the size of the innermost stable circular orbits and thus increases the luminosity of black hole's accretion disk.

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Mohaddese Heydari-Fard, Malihe Heydari-Fard, Nematollah Riazi. 2024-08-26. Galactic black hole immersed in a dark halo with its surrounding thin accretion disk. https://doi.org/10.1007/s10714-025-03382-5

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