JET SIGNATURES IN THE SPECTRA OF ACCRETING BLACK HOLES

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 γ-ray peak above ~1022 Hz, (ii) a break in the optical/UV spectrum, with a change from to , followed by another break at higher frequencies where the spectrum roughly returns to , and (iii) a pronounced synchrotron peak near or below ~1014 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 γ-rays to X-rays changes from in the BZ jet to during the launching of the transient plasmoid.