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arXiv · 2510.03925

Accretion Disk Luminosity and Topological Characteristics for a Schwarzschild Black Hole Surrounded by King Dark Matter Halo

Abstract

This study delves into the intricate properties of a Schwarzschild black hole enveloped by King dark matter in an isotropic configuration. The thermodynamic characteristics of this black hole are meticulously analyzed, and the dynamics of massive and massless particles in its vicinity are investigated. In examining the trajectories of massless particles, the shadow cast in the presence of King dark matter is explored, revealing virtual ranges for the corresponding parameters. For the dynamics of massive particles, the radius of the innermost stable circular orbit, angular momentum, energy, and angular velocity of a test particle within the King dark matter framework surrounding the black hole are calculated. The effect of King dark matter on the accretion disk energy flux, effective radiation temperature, differential luminosity, and spectral luminosity are then investigated. The stability of the photon sphere in the presence of King dark matter is also studied, and finally, the thermodynamic potentials of this black hole are examined from a topological perspective.

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Soroush Zare, Farokhnaz Hosseinifar, Luis Miguel Nieto, Dhruba Jyoti Gogoi, Kuantay Boshkayev, Ainur Urazalina, Hassan Hassanabadi. 2025-10-04. Accretion Disk Luminosity and Topological Characteristics for a Schwarzschild Black Hole Surrounded by King Dark Matter Halo. https://arxiv.org/abs/2510.03925

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