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Description
Understanding the impact of magnetic field topology on the evolution of black hole accretion disks is essential for interpreting high-energy astrophysical phenomena, such as jet formation and relativistic outflows. This work presents a comparative study of two different magnetic configurations—dipolar and multipolar—in the context of Magnetically Arrested Disks (MADs), utilizing two-dimensional general relativistic magnetohydrodynamic (GRMHD) simulations performed with the iharm3d code. Both setups are based on a modified Fishbone-Moncrief torus in Kerr spacetime, where vector potentials define distinct initial magnetic field structures. Using low-resolution simulations, we analyze the time evolution of key physical fluxes measured near the event horizon, including mass accretion rate, magnetic flux, angular momentum flux, and energy extraction efficiency. The results indicate that dipolar configurations lead to a more stable and efficient MAD state, whereas multipolar topologies generate irregular accretion patterns and lower energy extraction.