Some evidence of a double black hole in NGC 1194 active galactic nucleus?

1Vasylenko, AA, 2Fedorova, EV, 2Hnatyk, BI, 2Zhdanov, VI
1Main Astronomical Observatory of the National Academy of Sciences of Ukraine, Kyiv, Ukraine
2Astronomical Observatory of Taras Shevchenko National University of Kyiv, Kyiv, Ukraine
Kinemat. fiz. nebesnyh tel (Online) 2015, 31(1):22-31
Start Page: Extragalactic Astronomy
Language: Russian

On the basis of data from the XMM-Newton and INTEGRAL satellites, some properties of the X-ray emission from the active nucleus of the NGC 1194 galaxy are analyzed. Particular attention is paid to the energy region of X-ray spectrum between 6 and 7.5 keV, where, in addition to fluorescent iron lines FeKα (6.38 keV) and Fek (7.01 keV), we detected a new line with an energy of 6.51 keV with broad profile that is typical for relativistic iron line FeKα generated in an inclined accretion disk. Such a line configuration can be explained within the model of a double black hole system with an orbital period of the order of 6 yrs. Energies and profiles of the iron spectral lines FeKα correspond to the radiation of the accretion disks around Schwarzschild black holes with disk inclinations of 6 and 20 degrees. Some additional observations are needed to get a final conclusion about the structure of the lines and about the presence or absence of a double black hole in the core of NGC 1194.

Keywords: double black hole, NGC 1194

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