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arXiv · 1012.0762

A Distinctive Disk-Jet Coupling in the Seyfert-1 AGN NGC 4051

Ashley L. King·Jon M. Miller·Edward M. Cackett·Andy C. Fabian·Sera Markoff·Michael A. Nowak·Michael Rupen·Kayhan Gultekin·Mark T. Reynolds
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Abstract

We report on the results of a simultaneous monitoring campaign employing eight Chandra X-ray (0.5-10 keV) and six VLA/EVLA (8.4 GHz) radio observations of NGC 4051 over seven months. Evidence for compact jets is observed in the 8.4 GHz radio band; This builds on mounting evidence that jet production may be prevalent even in radio-quiet Seyferts. Assuming comparatively negligible local diffuse emission in the nucleus, the results also demonstrate an inverse correlation of L_radio proportional to L_X-ray ^(-0.72+/-0.04) . Current research linking the mass of supermassive black holes and stellar-mass black holes in the "low/hard" state to X-ray luminosities and radio luminosities suggest a "fundamental plane of accretion onto black holes" that has a positive correlation of L_radio proportional to L_X-ray^(0.67+/-0.12) . Our simultaneous results differ from this relation by more than 11 sigma, indicating that a separate mode of accretion and ejection may operate in this system. A review of the literature shows that the inverse correlation seen in NGC 4051 is seen in three other black hole systems, all of which accrete at near 10% of their Eddington luminosity, perhaps suggesting a distinct mode of disk-jet coupling at high Eddington fractions. We discuss our results in the context of disk and jets in black holes and accretion across the black hole mass scale.

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Ashley L. King, Jon M. Miller, Edward M. Cackett, Andy C. Fabian, Sera Markoff, Michael A. Nowak, Michael Rupen, Kayhan Gultekin, Mark T. Reynolds. 2011-01-13. A Distinctive Disk-Jet Coupling in the Seyfert-1 AGN NGC 4051. https://doi.org/10.1088/0004-637x%2F729%2F1%2F19

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