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arXiv · 1702.02197

Magnetic Origin of Black Hole Winds Across the Mass Scale

Keigo Fukumura·Demosthenes Kazanas·Chris Shrader·Ehud Behar·Francesco Tombesi·Ioannis Contopoulos
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Abstract

Black hole accretion disks appear to produce invariably plasma outflows that result in blue-shifted absorption features in their spectra. The X-ray absorption-line properties of these outflows are quite diverse, ranging in velocity from non-relativistic ($\sim 300$ km/sec) to sub-relativistic ($\sim 0.1c$ where $c$ is the speed of light) and a similarly broad range in the ionization states of the wind plasma. We report here that semi-analytic, self-similar magnetohydrodynamic (MHD) wind models that have successfully accounted for the X-ray absorber properties of supermassive black holes, also fit well the high-resolution X-ray spectrum of the accreting stellar-mass black hole, GRO J1655-40. This provides an explicit theoretical argument of their MHD origin (aligned with earlier observational claims) and supports the notion of a universal magnetic structure of the observed winds across all known black hole sizes.

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Keigo Fukumura, Demosthenes Kazanas, Chris Shrader, Ehud Behar, Francesco Tombesi, Ioannis Contopoulos. 2017-02-07. Magnetic Origin of Black Hole Winds Across the Mass Scale. https://arxiv.org/abs/1702.02197

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