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Magnetic and Electric Fields around the Black Hole in Cyg X-1

Yu. N. Gnedin·N. V. Borisov·T. M. Natsvlishvili·M. Yu. Piotrovich·N. A. Silant'ev
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Abstract

Analysis of polarimetric observations of X-ray binary Cyg X-1/HDE 226868 including the data obtained by BTA-6m allows to estimate the magnetic field magnitude near the inner radius of the accretion disk. The magnetic field magnitude occurred to be $\sim 10^{8}$ G. For power law of radial dependence of magnetic field into an accretion disk we estimates the value of an index of power law. For the Cyg X-1/HDE 226868 system the value of this index appears non less then two. If one accepts as a characteristic scale of a magnetic field generation region the dyadosphere radius, one can estimate the charge magnitude of a black hole. For Cyg X-1 this magnitude appears to be $\sim 0.01M\sqrt{G}$, where M is a black hole mass.

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Yu. N. Gnedin, N. V. Borisov, T. M. Natsvlishvili, M. Yu. Piotrovich, N. A. Silant'ev. 2003-04-09. Magnetic and Electric Fields around the Black Hole in Cyg X-1. https://arxiv.org/abs/astro-ph/0304158

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