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arXiv · 2111.08758

Blandford-Znajek Process in Quadratic Gravity

Jameson Dong·Nicolás Patiño·Yiqi Xie·Alejandro Cárdenas-Avendaño·Charles F. Gammie·Nicolás Yunes
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Abstract

The Blandford-Znajek process, which uses a magnetized plasma to extract energy from a rotating black hole, is one of the leading candidates for powering relativistic jets. In this work, we investigate the Blandford-Znajek process in two well-motivated quadratic gravity theories: scalar Gauss-Bonnet and dynamical Chern-Simons gravity. We solve analytically for a split-monopole magnetosphere to first order in the small-coupling approximation and second relative order in the slow-rotation approximation. The extracted power at fixed spin and magnetic flux is enhanced in scalar Gauss-Bonnet and reduced in dynamical Chern-Simons gravity, compared to general relativity. We find that there is a degeneracy between spin and the coupling constants of the theories at leading order in the slow rotation approximation that is broken at higher orders.

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Jameson Dong, Nicolás Patiño, Yiqi Xie, Alejandro Cárdenas-Avendaño, Charles F. Gammie, Nicolás Yunes. 2021-11-16. Blandford-Znajek Process in Quadratic Gravity. https://doi.org/10.1103/physrevd.105.044008

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