Temporal 1/f Fluctuations from Fractal Magnetic Fields in Black Hole Accretion Flow
نویسندگان
چکیده
Rapid fluctuation with a frequency dependence of 1/f (with α≃ 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 fluctuation (with α≃2) and a fractal magnetic structure (with the fractal dimension of D∼1.9). The fractal field configuration leads reconnection events with a variety of released energy and of duration, thereby producing 1/f fluctuations.
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تاریخ انتشار 2000