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arXiv · 2202.11116

Do Radio Active Galactic Nuclei Reflect X-ray Binary Spectral States?

Emily Moravec·Jiri Svoboda·Abhijeet Borkar·Peter Boorman·Daniel Kynoch·Francesca Panessa·Beatriz Mingo·Matteo Guainazzi
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Abstract

Over recent years there has been mounting evidence that accreting supermassive black holes in active galactic nuclei (AGN) and stellar mass black holes have similar observational signatures: thermal emission from the accretion disk, X-ray corona, and relativisitic jets. Further, there have been investigations into whether or not AGN have spectral states similar to that of X-ray binaries (XRBs) and what parallels can be drawn between the two using a hardness-intensity diagram (HID). To address whether AGN jets might be related to accretion states as in XRBs, we explore whether populations of radio-AGN classified according to their radio jet morphology (Fanaroff-Riley classes I and II; FR I and II), excitation class (HERG and LERG), and radio jet linear extent (compact to giant) occupy different and distinct regions of the AGN hardness-intensity diagram (total luminosity vs. hardness). We do this by cross correlating 15 catalogs of radio galaxies with the desired characteristics from the literature with XMM Newton and Swift X-ray and ultraviolet (UV) source catalogs. We calculate the luminosity and hardness from the X-ray and UV photometry, place the sources on the AGN hardness-intensity diagram, and search for separation of populations and analogies with the XRB spectral state HID. We find that (a) FR Is and IIs, (b) HERGs and LERGs, (c) FR I-LERGs and FR II-HERGs occupy distinct areas of the HID at a statistically significant level (p-value < 0.05) and no clear evidence for population distinction between the different radio jet linear extents. The separation between FR I-LERG and FR II-HERG populations is the strongest in this work. Our results indicate that radio-loud AGN occupy distinct areas of the HID depending on the morphology and excitation class, showing strong similarities to XRBs.

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Emily Moravec, Jiri Svoboda, Abhijeet Borkar, Peter Boorman, Daniel Kynoch, Francesca Panessa, Beatriz Mingo, Matteo Guainazzi. 2022-02-22. Do Radio Active Galactic Nuclei Reflect X-ray Binary Spectral States?. https://doi.org/10.1051/0004-6361%2F202142870

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