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arXiv · 2109.10288

Electric Penrose process: high-energy acceleration of ionized particles by non-rotating weakly charged black hole

Arman Tursunov·Bakhtinur Juraev·Zdeněk Stuchlík·Martin Kološ
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Abstract

In many astrophysical scenarios the charge of the black hole is often neglected due to unrealistically large values of the charge required for the Reissner-Nordstr\"om spacetime metric. However, black holes may possess small electric charge due to various selective accretion mechanisms. In this paper we investigate the effect of a small hypothetical electric charge of a Schwarzschild black hole on the ionization of a freely falling neutral particle and subsequent escape of the ionized particle from the black hole. We show that the energy of ionized particle can grow ultra-high and discuss distinguishing signatures of particle acceleration by weakly charged black holes. We also discuss a possible application of the proposed mechanism as an alternative cosmic ray acceleration scenario. In particular we show that the Galactic centre supermassive black hole is capable to act as a PeVatron of protons. The presented mechanism can serve as a simple toy model of a non-rotating compact object acting as a particle accelerator with a potential astrophysical implementations related to the cosmic ray physics and beyond.

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Arman Tursunov, Bakhtinur Juraev, Zdeněk Stuchlík, Martin Kološ. 2021-09-21. Electric Penrose process: high-energy acceleration of ionized particles by non-rotating weakly charged black hole. https://doi.org/10.1103/physrevd.104.084099

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