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arXiv · 2508.02211

Effect of magnetic field inclination on black hole jet power and particle acceleration

Enzo Figueiredo·Benoît Cerutti·Kyle Parfrey
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Abstract

Rotating black holes are known to launch relativistic jets and accelerate particles provided they accrete a magnetized plasma. However, it remains unclear how the global magnetic field orientation affects the jet powering efficiency. Here, we propose the first kinetic study of a collisionless plasma around a Kerr black hole that is embedded in a magnetic field inclined with respect to the black hole's spin axis. Using three-dimensional general-relativistic particle-in-cell simulations, we show that while oblique magnetic field configurations significantly reduce the jet power, particle acceleration remains highly efficient regardless. This suggests that black holes producing a weak jet could still be bright sources of nonthermal radiation and cosmic rays.

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Enzo Figueiredo, Benoît Cerutti, Kyle Parfrey. 2025-08-04. Effect of magnetic field inclination on black hole jet power and particle acceleration. https://doi.org/10.1051/0004-6361%2F202555826

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