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arXiv · 1705.11021

Numerical simulations of the Cosmic Battery in accretion flows around astrophysical black holes

Ioannis Contopoulos·Antonios Nathanail·Alexander Sadowski·Demosthenes Kazanas·Ramesh Narayan
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Abstract

We implement the KORAL code to perform two sets of very long general relativistic radiation magnetohydrodynamic simulations of an axisymmetric optically thin magnetized flow around a non-rotating black hole: one with a new term in the electromagnetic field tensor due to the radiation pressure felt by the plasma electrons on the comoving frame of the electron-proton plasma, and one without. The source of the radiation is the accretion flow itself. Without the new term, the system evolves to a standard accretion flow due to the development of the magneto-rotational instability (MRI). With the new term, however, the system eventually evolves to a magnetically arrested state (MAD) in which a large scale jet-like magnetic field threads the black hole horizon. Our results confirm the secular action of the Cosmic Battery in accretion flows around astrophysical black holes.

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Ioannis Contopoulos, Antonios Nathanail, Alexander Sadowski, Demosthenes Kazanas, Ramesh Narayan. 2017-05-31. Numerical simulations of the Cosmic Battery in accretion flows around astrophysical black holes. https://doi.org/10.1093/mnras%2Fstx2249

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