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Temporal 1/f^αFluctuations from Fractal Magnetic Fields in Black Hole Accretion Flow

T. Kawaguchi·S. Mineshige·M. Machida·R. Matsumoto·K. Shibata
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Abstract

Rapid fluctuation with a frequency dependence of $1/f^α$ (with $α\simeq 1 - 2$) is characteristic of radiation from black-hole objects. Its origin remains poorly understood. We examine the three-dimensional magnetohydrodynamical (MHD) simulation data, finding that a magnetized accretion disk exhibits both $1/f^α$ fluctuation (with $α\simeq 2$) and a fractal magnetic structure (with the fractal dimension of $D \sim 1.9$). The fractal field configuration leads reconnection events with a variety of released energy and of duration, thereby producing $1/f^α$ fluctuations.

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T. Kawaguchi, S. Mineshige, M. Machida, R. Matsumoto, K. Shibata. 1999-12-24. Temporal 1/f^αFluctuations from Fractal Magnetic Fields in Black Hole Accretion Flow. https://doi.org/10.1093/pasj%2F52.1.l1

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