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arXiv · 2503.06682

Properties of low angular momentum general relativistic MHD accretion flows around black holes

Samik Mitra
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Abstract

In this proceeding, we provide a novel approach to study the General Relativistic Magnetohydrodynamic (GRMHD) accretion flows around rotating black holes (BHs). In doing so, we choose a sub-Keplerian distribution of angular momentum of the flow, which is necessary for the accreting matter to reach the event horizon of the BH. Further, we consider the convergent flow to be confined about the disk mid-plane and is threaded by both radial ($b^r$) and toroidal ($b^\phi$) magnetic field components. For simplicity, we neglect any motion along the vertical ($\theta$) direction, maintaining a vertical (hydrostatic) equilibrium about the midplane. With this, we describe the family of multi-trans-magnetosonic accretion solutions around rotating BHs and examine how the conserved magnetic flux ($\Phi$) and BH spin ($a_{\rm k}$) affect the accretion flow properties. Finally, we provide an insight into the thermal emissions from the magnetized disk for a specific set of accretion solutions.

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Samik Mitra. 2025-03-09. Properties of low angular momentum general relativistic MHD accretion flows around black holes. https://arxiv.org/abs/2503.06682

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