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arXiv · 1510.08860

Jet Signatures in the Spectra of Accreting Black Holes

Michael O' Riordan·Asaf Pe'er·Jonathan C. McKinney
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Abstract

Jets are observed as radio emission in active galactic nuclei and during the low/hard state in X-ray binaries (XRBs), but their contribution at higher frequencies has been uncertain. We study the dynamics of jets in XRBs using the general-relativistic magnetohydrodynamic code HARM. We calculate the high-energy spectra and variability properties using a general-relativistic radiative transport code based on grmonty. We find the following signatures of jet emission (i) a significant gamma-ray peak above ~10^22 Hz, (ii) a break in the optical/UV spectrum, with a change in luminosity from L ~ nu^0 to L ~ nu, followed by another break at higher frequencies where the spectrum roughly returns to L ~ nu^0, and (iii) a pronounced synchrotron peak near or below ~10^14 Hz indicates that a significant fraction of any observed X-ray emission originates in the jet. We investigate the variability during a large-scale magnetic field inversion in which the Blandford-Znajek (BZ) jet is quenched and a new transient hot reconnecting plasmoid is launched by the reconnecting field. The ratio of the gamma-rays to X-rays changes from L_gamma / L_X > 1 in the BZ jet to L_gamma / L_X < 1 during the launching of the transient plasmoid.

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Michael O' Riordan, Asaf Pe'er, Jonathan C. McKinney. 2016-01-27. Jet Signatures in the Spectra of Accreting Black Holes. https://doi.org/10.3847/0004-637x%2F819%2F2%2F95

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