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arXiv · 2503.04321

Effect of spin on the dynamics of multi-component trans-relativistic accretion flows around Kerr black holes

Kalyanbrata Pal·Souvik Ghose·Shilpa Sarkar·Tapas K. Das
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Abstract

We investigate the axially symmetric accretion of low angular momentum hydrodynamic matter onto a rotating black hole. The gravitational field under consideration is assumed to be described by a pseudo-Newtonian Kerr potential. The accreting matter consists of different species defined by a relativistic equation of state with a variable adiabatic index.We construct and solve the hydrodynamical conservation equations governing such a flow, and find out the corresponding stationary integral solutions. We find that depending on the values of initial boundary conditions, accretion flow may exhibit multi-transonic behaviour, and a standing shock may form. We investigate, in minute detail, how the spin angular momentum of the black hole, as well as the composition of the accreting matter influence the dynamics of accretion flow and the astrophysics of shock formation in the aforementioned accreting black hole systems.

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Kalyanbrata Pal, Souvik Ghose, Shilpa Sarkar, Tapas K. Das. 2025-03-06. Effect of spin on the dynamics of multi-component trans-relativistic accretion flows around Kerr black holes. https://arxiv.org/abs/2503.04321

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