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arXiv · 2411.18599

Magnetically arrested advective accretion flows and jets/outflows around stellar mass black holes: Explaining hard state ULXs with GRMHD simulations

Rohan Raha·Banibrata Mukhopadhyay·Koushik Chatterjee
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Abstract

An optically thin advective accretion disk is crucial for explaining the hard state of black hole sources. Using general relativistic magnetohydrodynamic (GRMHD) simulations, we investigate how a large-scale, strong magnetic field influences accretion and outflows/jets, depending on the field geometry, magnetic field strength, and the spin parameter of the black hole. We simulate a sub-Eddington, advective disk-outflow system in the presence of a strong magnetic field, which likely remains in the hard state. The model simulations based on HARMPI successfully explain ultra-luminous X-ray sources (ULXs) in the hard state, typically observed with luminosities ranging from $10^{39}$ - $10^{40}$ ergs s$^{-1}$. Our simulations generally describe the bright, hard state of stellar-mass black hole sources without requiring a super-Eddington accretion rate. This work explores the characteristics of ULXs without invoking intermediate-mass black holes. The observed high luminosity is attributed to the energy stored in the strong magnetic fields, which can generate super-Eddington luminosity. The combined energy of the matter and magnetic field leads to such significant luminosity.

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Rohan Raha, Banibrata Mukhopadhyay, Koushik Chatterjee. 2024-11-27. Magnetically arrested advective accretion flows and jets/outflows around stellar mass black holes: Explaining hard state ULXs with GRMHD simulations. https://arxiv.org/abs/2411.18599

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