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arXiv · 1804.09679

The distinguishing signature of Magnetic Penrose Process

Naresh Dadhich·Arman Tursunov·Bobomurat Ahmedov·Zdeněk Stuchlík
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Abstract

In this Letter, we wish to point out that the distinguishing feature of Magnetic Penrose process (MPP) is its super high efficiency exceeding $100\%$ (which was established in mid 1980s for discrete particle accretion) of extraction of rotational energy of a rotating black hole electromagnetically for a magnetic field of milli Gauss order. Another similar process, which is also driven by electromagnetic field, is Blandford-Znajek mechanism (BZ), which could be envisaged as high magnetic field limit MPP as it requires threshold magnetic field of order $10^4$G. Recent simulation studies of fully relativistic magnetohydrodynamic flows have borne out super high efficiency signature of the process for high magnetic field regime; viz BZ. We would like to make a clear prediction that similar simulation studies of MHD flows for low magnetic field regime, where BZ would be inoperative, would also have super efficiency.

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Naresh Dadhich, Arman Tursunov, Bobomurat Ahmedov, Zdeněk Stuchlík. 2018-04-25. The distinguishing signature of Magnetic Penrose Process. https://doi.org/10.1093/mnrasl/sly073

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