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arXiv · 1512.00729

Disk Emission from Magneto-hydrodynamic Simulations of Spinning Black Holes

Jeremy D. Schnittman·Julian H. Krolik·Scott C. Noble
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Abstract

We present the results of a new series of global 3D relativistic magneto-hydrodynamic (MHD) simulations of thin accretion disks around spinning black holes. The disks have aspect ratios of $H/R\sim 0.05$ and spin parameters $a/M=0, 0.5, 0.9$, and $0.99$. Using the ray-tracing code Pandurata, we generate broad-band thermal spectra and polarization signatures from the MHD simulations. We find that the simulated spectra can be well fit with a simple, universal emissivity profile that better reproduces the behavior of the emission from the inner disk, compared to traditional analyses carried out using a Novikov-Thorne thin disk model. Lastly, we show how spectropolarization observations can be used to convincingly break the spin-inclination degeneracy well-known to the continuum fitting method of measuring black hole spin.

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Jeremy D. Schnittman, Julian H. Krolik, Scott C. Noble. 2015-12-02. Disk Emission from Magneto-hydrodynamic Simulations of Spinning Black Holes. https://doi.org/10.3847/0004-637x%2F819%2F1%2F48

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